Solder alloys

Solder is a metallic material that is used to connect metal workpieces. The choice of specific solder alloys depends on their melting point, chemical reactivity, mechanical properties, toxicity, and other properties. Hence a wide range of solder alloys exist, and only major ones are listed below. Since early 2000s the use of lead in solder alloys is discouraged by several governmental guidelines in the European Union, Japan and other countries,[1] such as Restriction of Hazardous Substances Directive and Waste Electrical and Electronic Equipment Directive.

Soldering copper pipes using a propane torch and a lead-free solder

Solder alloys
CompositionM.P. S/L (°C)ToxicEutecticComments
Sn50Zn49Cu1 200/300[2]NoGalvanite Lead-free galvanizing solder formulation designed specifically for high quality repairs to galvanized steel surfaces. Simple, effective and easy to use, in both manufacturing and field applications. Metallurgically bonds to the steel, for a seamless protective barrier.[2]
Sn95.5Cu4Ag0.5 226/260[3]NoKappFree provides good joint strength, vibration resistance, and thermal cycle fatigue resistance in both piping and electrical products as opposed to tin-lead solders. Higher working temperature. Wets well to brass, copper, and stainless steel. Good electrical conductivity.[3]
Sn90Zn7Cu3 200/222[4]NoKapp Eco-Babbitt[4] Commonly used in capacitor manufacturing as protective coating to shield against electromotive force (EMF) and electromagnetic interference (EMI) with the specified performance of the capacitor, to prevent current and charge leakage out of and within the layers of the capacitor, and to prevent the development of electron flows within the coating material itself, that would diminish capacitor performance, coating, and capacitor life.[4]
Pb90Sn10 268/302[5] 275/302[6]PbNoSn10, UNS L54520, ASTM10B. Balls for CBGA components, replaced by Sn95.5Ag3.9Cu0.6.[7] Low cost and good bonding properties. Rapidly dissolves gold and silver, not recommended for those.[8] Used for fabrication of car radiators and fuel tanks, for coating and bonding of metals for moderate service temperatures. Body solder.[9] Has low thermal EMF, can be used as an alternative to Cd70 where parasitic thermocouple voltage has to be avoided.[10]
Pb88Sn12 254/296[9]PbNoUsed for fabrication of car radiators and fuel tanks, for coating and bonding of metals for moderate service temperatures. Body solder.
Pb85Sn15 227/288[9]PbNoUsed for coating tubes and sheets and fabrication of car radiators. Body solder.
Pb80Sn20 183/280[6]PbNoSn20, UNS L54711. Used for coating radiator tubes for joining fins.[9]
Pb80Sb15Sn5 300PbWhite Metal Capping. Used for locking mineshaft winding ropes into their tapered end sockets or 'capels'.[11]
Pb75Sn25 183/266[5]PbNoCrude solder for construction plumbing works, flame-melted. Used for soldering car engine radiators. Used for machine, dip and hand soldering of plumbing fixtures and fittings. Superior body solder.[9]
Pb70Sn30 185/255[5] 183/257[6]PbNoSn30, UNS L54280, crude solder for construction plumbing works, flame-melted, good for machine and torch soldering.[12] Used for soldering car engine radiators. Used for machine, dip and hand soldering of plumbing fixtures and fittings. Superior body solder.[9]
Pb68Sn32 253PbNo"Plumber solder", for construction plumbing works[13]
Pb68Sn30Sb2 185/243[6]PbNoPb68
Sn30Pb50Zn20 177/288[14]PbNoKapp GalvRepair Economical solder for repairing & joining most metals including Aluminum and cast Iron. Have been used for cast Iron and galvanized surface repair.[14]
Sn33Pb40Zn28 230/275[14]PbNoEconomical solder for repairing & joining most metals including Aluminum and cast Iron. Have been used for cast Iron and galvanized surface repair.[14]
Pb67Sn33 187–230PbNoPM 33, crude solder for construction plumbing works, flame-melted, temperature depends on additives
Pb65Sn35 183/250[6]PbNoSn35. Used as a cheaper alternative of Pb60Sn40 for wiping and sweating joints.[9]
Pb60Sn40 183/238[5] 183/247[6]PbNoSn40, UNS L54915. For soldering of brass and car radiators.[12] For bulk soldering, and where wider melting point range is desired. For joining cables. For wiping and joining lead pipes. For repairs of radiators and electrical systems.[9]
Pb55Sn45 183/227[9]PbNoFor soldering radiator cores, roof seams, and for decorative joints.
Sn50Pb50 183/216[5] 183–212[6]PbNoSn50, UNS L55030. "Ordinary solder", for soldering of brass, electricity meters, gas meters, formerly also tin cans. General purpose, for standard tinning and sheetmetal work. Becomes brittle below ?150 °C.[15][13] Low cost and good bonding properties. Rapidly dissolves gold and silver, not recommended for those.[8] For wiping and assembling plumbing joints for non-potable water.[9]
Sn50Pb48.5Cu1.5 183/215[16]PbNoSavbit, Savbit 1, Sav1. Minimizes dissolution of copper. Originally designed to reduce erosion of the soldering iron tips. About 100 times slower erosion of copper than ordinary tin/lead alloys. Suitable for soldering thin copper platings and very thin copper wires.[17]
Sn60Pb40 183/190[5] 183/188[6]PbNearSn60, ASTM60A, ASTM60B. Common in electronics, most popular leaded alloy for dipping. Low cost and good bonding properties. Used in both SMT and through-hole electronics. Rapidly dissolves gold and silver, not recommended for those.[8] Slightly cheaper than Sn63Pb37, often used instead for cost reasons as the melting point difference is insignificant in practice. On slow cooling gives slightly duller joints than Sn63Pb37.[17]
Sn60Pb38Cu2 183/190[6][18]PbCu2. Copper content increases hardness of the alloy and inhibits dissolution of soldering iron tips and part leads in molten solder.
Sn60Pb39Cu1 PbNo
Sn62Pb38 183PbNear"Tinman's solder", used for tinplate fabrication work.[13]
Sn63Pb37 183[19]PbYesSn63, ASTM63A, ASTM63B. Common in electronics; exceptional tinning and wetting properties, also good for stainless steel. One of the most common solders. Low cost and good bonding properties. Used in both SMT and through-hole electronics. Rapidly dissolves gold and silver, not recommended for those.[8] Sn60Pb40 is slightly cheaper and is often used instead for cost reasons, as the melting point difference is insignificant in practice. On slow cooling gives slightly brighter joints than Sn60Pb40.[17]
Sn63Pb37P0.0015–0.04 183[20]PbYesSn63PbP. A special alloy for HASL machines. Addition of phosphorus reduces oxidation. Unsuitable for wave soldering as it may form metal foam.
Sn62Pb37Cu1 183[18]PbYesSimilar to Sn63Pb37. Copper content increases hardness of the alloy and inhibits dissolution of soldering iron tips and part leads in molten solder.
Sn70Pb30 183/193[5]PbNoSn70
Sn90Pb10 183/213[6]PbNoformerly used for joints in food industry
Sn95Pb5 238PbNoplumbing and heating
Pb92Sn5.5Ag2.5 286/301[18]PbNoFor higher-temperature applications.
Pb80Sn12Sb8 PbNoUsed for soldering iron and steel[13]
Pb80Sn18Ag2 252/260[6]PbNoUsed for soldering iron and steel[13]
Pb79Sn20Sb1 184/270PbNoSb1
Pb55Sn43.5Sb1.5 PbNoGeneral purpose solder. Antimony content improves mechanical properties but causes brittleness when soldering cadmium, zinc, or galvanized metals.[13]
Sn43Pb43Bi14 144/163[5]PbNoBi14. Good fatigue resistance combined with low melting point. Contains phases of tin and lead-bismuth.[21] Useful for step soldering.
Sn46Pb46Bi8 120/167[6]PbNoBi8
Bi52Pb32Sn16 96Pbyes?Bi52. Good fatigue resistance combined with low melting point. Reasonable shear strength and fatigue properties. Combination with lead-tin solder may dramatically lower melting point and lead to joint failure.[21]
Bi46Sn34Pb20 100/105[6]PbNoBi46
Sn62Pb36Ag2 179[5]PbYesSn62. Common in electronics. The strongest tin-lead solder. Appearance identical to Sn60Pb40 or Sn63Pb37. Crystals of Ag3Sn may be seen growing from the solder. Extended heat treatment leads to formation of crystals of binary alloys. Silver content decreases solubility of silver, making the alloy suitable for soldering silver-metallized surfaces, e.g. SMD capacitors and other silver-metallized ceramics.[15][17][21] Not recommended for gold.[8] General-purpose.
Sn62.5Pb36Ag2.5 179[5]PbYes
Pb88Sn10Ag2 268/290[5] 267/299[22]PbNoSn10, Pb88. Silver content reduces solubility of silver coatings in the solder. Not recommended for gold.[8] Forms a eutectic phase, not recommended for operation above 120 °C.
Pb90Sn5Ag5 292[5]PbYes
Pb92.5Sn5Ag2.5 287/296[5] 299/304[6]PbNoPb93.
Pb93.5Sn5Ag1.5 296/301[5] 305/306[6]PbNoPb94, HMP alloy, HMP. Service temperatures up to 255 °C. Useful for step soldering. Also can be used for extremely low temperatures as it remains ductile down to −200 °C, while solders with more than 20% tin become brittle below −70 °C. Higher strength and better wetting than Pb95Sn5.[17]
Pb95.5Sn2Ag2.5 299/304[5]PbNo
In97Ag3 143[23]–YesWettability and low-temperature malleability of indium, strength improved by addition of silver. Particularly good for cryogenic applications. Used for packaging of photonic devices.
In90Ag10 143/237[24]–NoNearly as wettable and low-temperature malleable as indium. Large plastic range. Can solder silver, fired glass and ceramics.
In75Pb25 156/165[8]PbNoLess gold dissolution and more ductile than lead-tin alloys. Used for die attachment, general circuit assembly and packaging closures.[8]
In70Pb30 160/174[5] 165/175[6][25]PbNoIn70. Suitable for gold, low gold-leaching. Good thermal fatigue properties.
In60Pb40 174/185[5] 173/181[6]PbNoIn60. Low gold-leaching. Good thermal fatigue properties.
In50Pb50 180/209[8] 178/210[6]PbNoIn50. Only one phase. Resoldering with lead-tin solder forms indium-tin and indium-lead phases and leads to formation of cracks between the phases, joint weakening and failure.[21] On gold surfaces gold-indium intermetallics tend to be formed, and the joint then fails in the gold-depleted zone and the gold-rich intermetallic.[26] Less gold dissolution and more ductile than lead-tin alloys.[8] Good thermal fatigue properties.
In50Sn50 118/125[27]–NoCerroseal 35. Fairly well wets glass, quartz and many ceramics. Malleable, can compensate some thermal expansion differences. Low vapor pressure. Used in low temperature physics as a glass-wetting solder.[28]
In70Sn15Pb9.6Cd5.4 125[29]Cd, Pb
Pb75In25 250/264[8] 240/260[30]PbNoIn25. Low gold-leaching. Good thermal fatigue properties. Used for die attachment of e.g. GaAs dies.[26] Used also for general circuit assembly and packaging closures. Less dissolution of gold and more ductile than tin-lead alloy.[8]
Sn70Pb18In12 162[5]
154/167[31]		PbYesGeneral purpose. Good physical properties.
Sn37.5Pb37.5In25 134/181[8]PbNoGood wettability. Not recommended for gold.[8]
Pb90In5Ag5 290/310[5]PbNo
Pb92.5In5Ag2.5 300/310[5]PbNoUNS L51510. Minimal leaching of gold, good thermal fatigue properties. Reducing atmosphere frequently used..
Pb92.5In5Au2.5 300/310[6]PbNoIn5
Pb94.5Ag5.5 305/364[6] 304/343[32]PbNoAg5.5, UNS L50180
Pb95Ag5 305/364[33]PbNo
Pb97.5Ag2.5 303[5] 304[6] 304/579[34]Pbyes noAg2.5, UNS L50132. Used during World War II to conserve tin. Poor corrosion resistance; joints suffered corrosion in both atmospheric and underground conditions, all had to be replaced with Sn-Pb alloy joints.[35] Torch solder.
Sn97.5Pb1Ag1.5 305PbYesImportant for hybrid circuits assembly.[15]
Pb97.5Ag1.5Sn1 309[5]PbYesAg1.5, ASTM1.5S. High melting point, used for commutators, armatures, and initial solder joints where remelting when working on nearby joints is undesirable.[12] Silver content reduces solubility of silver coatings in molten solder. Not recommended for gold.[8] Standard PbAgSn eutectic solder, wide use in semiconductor assembly. Reducing protective atmosphere (e.g. 12% hydrogen) often used. High creep resistance, for use at both elevated and cryogenic temperatures.
Pb54Sn45Ag1 177–210Pbexceptional strength, silver gives it a bright long-lasting finish; ideal for stainless steel[12]
Pb96Ag4 305Pbhigh-temperature joints[12]
Pb96Sn2Ag2 252/295[6]PbPb96
Sn61Pb36Ag3 Pb[15]
Sn56Pb39Ag5 Pb[15]
Sn98Ag2 –[15]
Sn65Ag25Sb10 233–YesVery high tensile strength. For die attachment. Very brittle. Old Motorola die attach solder.
Sn96.5Ag3.0Cu0.5 217/220 217/218[6][36]–NearSAC305. It is the JEITA recommended alloy for wave and reflow soldering, with alternatives SnCu for wave and SnAg and SnZnBi for reflow soldering. Usable also for selective soldering and dip soldering. At high temperatures tends to dissolve copper; copper buildup in the bath has detrimental effect (e.g. increased bridging). Copper content must be maintained between 0.4–0.85%, e.g. by refilling the bath with Sn97Ag3 alloy. Nitrogen atmosphere can be used to reduce losses by dross formation. Dull, surface shows formation of dendritic tin crystals. Weakens at thermal cycling, concern of whisker growth, large Ag3Sn intermetallic platelet precipitates causing mechanical weakening and poor shock/drop performance. Tendency to creep.[37]
Sn98.5Ag1.0Cu0.5 220–225–NearSAC105 alloy contains the least amount of silver among lead-free solders. It is compatible with all flux types and is relatively inexpensive; it exhibits good fatigue resistance, wetting and solder joint reliability
Sn95.8Ag3.5Cu0.7 217–218–NearSN96C-Ag3.5 A commonly used alloy. Used for wave soldering. Usable also for selective soldering and dip soldering. At high temperatures tends to dissolve copper; copper buildup in the bath has detrimental effect (e.g. increased bridging). Copper content must be maintained between 0.4–0.85%, e.g. by refilling the bath with Sn96.5Ag3.5 alloy (designated e.g. SN96Ce). Nitrogen atmosphere can be used to reduce losses by dross formation. Dull, surface shows formation of dendritic tin crystals.
Sn95.6Ag3.5Cu0.9 217–YesDetermined by NIST to be truly eutectic.
Sn95.5Ag3.8Cu0.7 217[38]–NearSN96C. Preferred by the European IDEALS consortium for reflow soldering. Usable also for selective soldering and dip soldering. At high temperatures tends to dissolve copper; copper buildup in the bath has detrimental effect (e.g. increased bridging). Copper content must be maintained between 0.4–0.85%, e.g. by refilling the bath with Sn96.2Ag3.8 alloy (designated e.g. SN96Ce). Nitrogen atmosphere can be used to reduce losses by dross formation. Dull, surface shows formation of dendritic tin crystals.
Sn95.25Ag3.8Cu0.7Sb0.25 –Preferred by the European IDEALS consortium for wave soldering.
Sn95.5Ag3.9Cu0.6 217[39]–YesRecommended by the US NEMI consortium for reflow soldering. Used as balls for BGA/CSP and CBGA components, a replacement for Sn10Pb90. Solder paste for rework of BGA boards.[7] Alloy of choice for general SMT assembly.
Sn95.5Ag4Cu0.5 217[40]–YesSAC405. Lead-Free, Cadmium Free formulation designed specifically to replace Lead solders in Copper and Stainless Steel plumbing, and in electrical and electronic applications.[3]
Sn96.5Ag3.5 221[5]–YesSn96, Sn96.5, 96S. Fine lamellar structure of densely distributed Ag3Sn. Annealing at 125 °C coarsens the structure and softens the solder.[7] Creeps via dislocation climb as a result of lattice diffusion.[41] Used as wire for hand soldering rework; compatible with SnCu0.7, SnAg3Cu0.5, SnAg3.9Cu0.6, and similar alloys. Used as solder spheres for BGA/CSP components. Used for step soldering and die attachment in high power devices. Established history in the industry.[7] Widely used. Strong lead-free joints. Silver content minimizes solubility of silver coatings. Not recommended for gold.[8] Marginal wetting. Good for step soldering. Used for soldering stainless steel as it wets stainless steel better than other soft solders. Silver content does not suppress dissolution of silver metallizations.[17] High tin content allows absorbing significant amount of gold without embrittlement.[42]
Sn96Ag4 221–229–NoASTM96TS. "Silver-bearing solder". Food service equipment, refrigeration, heating, air conditioning, plumbing.[12] Widely used. Strong lead-free joints. Silver content minimizes solubility of silver coatings. Not recommended for gold.[8]
Sn95Ag5 221/254[43]–NoWidely used. Strong lead-free joints. Silver content minimizes solubility of silver coatings. Not recommended for gold. Produces strong and ductile joints on Copper and Stainless Steel. The resulting joints have high tolerance to vibration and stress, with tensile strengths to 30,000 psi on Stainless.[43]
Sn94Ag6 221/279[43]–NoProduces strong and ductile joints on Copper and Stainless Steel. The resulting joints have high tolerance to vibration and stress, with tensile strengths to 30,000 psi on Stainless.[43]
Sn93Ag7 221/302[43]–NoProduces strong and ductile joints on Copper and Stainless Steel. The resulting joints have high tolerance to vibration and stress, with tensile strengths to 31,000 psi on Stainless.[43] Audio industry standard for vehicle and home theater speaker installations. Its 7% Silver content requires a higher temperature range, but yields superior strength and vibration resistance.[44]
Sn95Ag4Cu1 –
Sn 232–PureSn99. Good strength, non-dulling. Use in food processing equipment, wire tinning, and alloying.[12] Susceptible to tin pest.
Sn99.3Cu0.7 228[1]–YesSn99Cu1. Also designated as Sn99Cu1. Cheap alternative for wave soldering, recommended by the US NEMI consortium. Coarse microstructure with ductile fractures. Sparsely distributed Cu6Sn5.[1][45] Forms large dendritic ß-tin crystals in a network of eutectic microstructure with finely dispersed Cu6Sn5. High melting point unfavorable for SMT use. Low strength, high ductility. Susceptible to tin pest.[41] Addition of small amount of nickel increases its fluidity; the highest increase occurs at 0.06% Ni. Such alloys are known as nickel modified or nickel stabilized.[46]
Sn99.3Cu0.7Ni0.05Ge0.009 227[47]YesSn100C, a lead-free silver-free nickel-stabilized alloy. Similar to Sn99Cu1. The nickel content lowers copper erosion and promotes shiny solder fillet. The presence of germanium promotes flow and reduces dross formation. Performance similar to SAC alloys at lower cost. Dross formation rate comparable to lead-tin alloys.
Sn99.3Cu0.7Ni?Bi? 227[48]YesK100LD, a lead-free silver-free nickel-stabilized alloy, with low dissolving (LD) of copper. Proprietary of Kester. Similar to Sn99Cu1. The nickel content lowers copper erosion and promotes shiny solder fillet. Bismuth acts in synergy with nickel to further reduce copper dissolution and reduces surface tension. Performance similar to SAC alloys at lower cost. K100LDa has 0.2% copper, used to refill wave soldering pots to counteract copper buildup. Lower than optimal nickel content to avoid patents?[49]
Sn99Cu0.7Ag0.3 217/228[50]–NoSCA, SAC, or SnAgCu. Tin-silver-copper alloy. Relatively low-cost lead-free alloy for simple applications. Can be used for wave, selective and dip soldering. At high temperatures tends to dissolve copper; copper buildup in the bath has detrimental effect (e.g. increased bridging). Copper content must be maintained between 0.4–0.85%, e.g. by refilling the bath with Sn96.2Ag3.8 alloy (designated e.g. SN96Ce). Nitrogen atmosphere can be used to reduce losses by dross formation. Dull, surface shows formation of dendritic tin crystals.
Sn97Cu3 227/250[51] 232/332[9]–For high-temperature uses. Allows removing insulation from an enameled wire and applying solder coating in a single operation. For radiator repairs, stained glass windows, and potable water plumbing.
Sn97Cu2.75Ag0.25 228/314[9]–High hardness, creep-resistant. For radiators, stained glass windows, and potable water plumbing. Excellent high-strength solder for radiator repairs. Wide range of patina and colors.
Zn100 419–PureFor soldering aluminium. Good wettability of aluminium, relatively good corrosion resistance.[52]
Bi100 271–PureUsed as a non-superconducting solder in low-temperature physics. Does not wet metals well, forms a mechanically weak joint.[28]
Sn91Zn9 199[53]–YesKappAloy9 Designed specifically for Aluminum-to-Aluminum and Aluminum-to-Copper soldering. It has good corrosion resistance and tensile strength. Lies between soft solder and silver brazing alloys, thereby avoiding damage to critical electronics and substrate deformation and segregation. Best solder for Aluminum wire to Copper busses or Copper wire to Aluminum busses or contacts.[53] UNS#: L91090
Sn85Zn15 199/260[53]–NoKappAloy15 Designed specifically for Aluminum-to-Aluminum and Aluminum-to-Copper soldering. It has good corrosion resistance and tensile strength. Lies between soft solder and silver brazing alloys, thereby avoiding damage to critical electronics and substrate deformation and segregation. Has a wide plastic range this makes it ideal for hand soldering Aluminum plates and parts, allowing manipulation of the parts as the solder cools.[53]
Zn95Al5 382–YesFor soldering aluminium. Good wetting.[52]
Sn91.8Bi4.8Ag3.4 211/213[54]–NoDo not use on lead-containing metallizations.[55]
Sn70Zn30 199/316[53]–NoKappAloy30 For soldering of aluminium. Good wetting. Used extensively in spray wire form for capacitors and other electronic parts. Higher temperature and higher tensile strength compared to 85Sn/15Zn and 91Sn/9Zn.[53]
Sn80Zn20 199/288[53]–NoKappAloy20 For soldering of aluminium. Good wetting. Used extensively in spray wire form for capacitors and other electronic parts. Higher temperature and higher tensile strength compared to 85Sn/15Zn and 91Sn/9Zn.[53]
Sn60Zn40 199/343[53]–NoKappAloy40 For soldering of aluminium. Good wetting. Used extensively in spray wire form for capacitors and other electronic parts. Higher temperature and higher tensile strength compared to 85Sn/15Zn and 91Sn/9Zn.[53]
Pb63Sn35Sb2 185/243[6]PbNoSb2
Pb63Sn34Zn3 170/256PbNoPoor wetting of aluminium. Poor corrosion rating.[35]
Pb92Cd8 310?Cd, Pb?For soldering aluminium.[56][57]
Sn48Bi32Pb20 140/160[18]PbNoFor low-temperature soldering of heat-sensitive parts, and for soldering in the vicinity of already soldered joints without their remelting.
Sn89Zn8Bi3 191–198–Prone to corrosion and oxidation due to its zinc content. On copper surfaces forms a brittle Cu-Zn intermetallic layer, reducing the fatigue resistance of the joint; nickel plating of copper inhibits this.[58]
Sn83.6Zn7.6In8.8 181/187[59]–NoHigh dross due to zinc.[60]
Sn86.5Zn5.5In4.5Bi3.5 174/186[61]–NoLead-free. Corrosion concerns and high drossing due to zinc content.
Sn86.9In10Ag3.1 204/205[62]–Potential use in flip-chip assembly, no issues with tin-indium eutectic phase.
Sn95Ag3.5Zn1Cu0.5 221L[58]–No
Sn95Sb5 235/240[5] 232/240[6]–NoSb5, ASTM95TA. The US plumbing industry standard. It displays good resistance to thermal fatigue and good shear strength. Forms coarse dendrites of tin-rich solid solution with SbSn intermetallic dispersed between. Very high room-temperature ductility. Creeps via viscous glide of dislocations by pipe diffusion. More creep-resistant than SnAg3.5. Antimony can be toxic. Used for sealing chip packagings, attaching I/O pins to ceramic substrates, and die attachment; a possible lower-temperature replacement of AuSn.[41] High strength and bright finish. Use in air conditioning, refrigeration, some food containers, and high-temperature applications.[12] Good wettability, good long-term shear strength at 100 °C. Suitable for potable water systems. Used for stained glass, plumbing, and radiator repairs.
Sn97Sb3 232/238[63]–No
Sn99Sb1 232/235[64]–No
Sn99Ag0.3Cu0.7 –
Sn96.2Ag2.5Cu0.8Sb0.5 217–225 217[6]–Ag03A. Patented by AIM alliance.
Sn88In8.0Ag3.5Bi0.5 197–208–Patented by Matsushita/Panasonic.
Bi57Sn42Ag1 137/139 139/140[65]–Addition of silver improves mechanical strength. Established history of use. Good thermal fatigue performance. Patented by Motorola.
Bi58Sn42 138[5][8]–YesBi58. Reasonable shear strength and fatigue properties. Combination with lead-tin solder may dramatically lower melting point and lead to joint failure.[21] Low-temperature eutectic solder with high strength.[8] Particularly strong, very brittle.[5] Used extensively in through-hole technology assemblies in IBM mainframe computers where low soldering temperature was required. Can be used as a coating of copper particles to facilitate their bonding under pressure/heat and creating a conductive metallurgical joint.[58] Sensitive to shear rate. Good for electronics. Used in thermoelectric applications. Good thermal fatigue performance.[66] Established history of use. Expands slightly on casting, then undergoes very low further shrinkage or expansion, unlike many other low-temperature alloys which continue changing dimensions for some hours after solidification.[28]
Bi58Pb42 124/126[67]Pb
In80Pb15Ag5 142/149[6]
149/154[68]		PbNoIn80. Compatible with gold, minimum gold-leaching. Resistant to thermal fatigue. Can be used in step soldering.
Pb60In40 195/225[6]PbNoIn40. Low gold-leaching. Good thermal fatigue properties.
Pb70In30 245/260[6]PbNoIn30
Sn37.5Pb37.5In26 134/181[6]PbNoIn26
Sn54Pb26In20 130/154[6] 140/152[69]PbNoIn20
Pb81In19 270/280[6] 260/275[70]PbNoIn19. Low gold-leaching. Good thermal fatigue properties.
In52Sn48 118–YesIn52. Suitable for the cases where low-temperature soldering is needed. Can be used for glass sealing.[58] Sharp melting point. Good wettability of glass, quartz, and many ceramics. Good low-temperature malleability, can compensate for different thermal expansion coefficients of joined materials.
Sn52In48 118/131[5]–Novery low tensile strength
Sn58In42 118/145[71]–No
Sn51.2Pb30.6Cd18.2 145[72]Cd, PbYesGeneral-purpose. Maintains creep strength well. Unsuitable for gold.
Sn77.2In20Ag2.8 175/187[73]–NoSimilar mechanical properties with Sn63Pb37, Sn62Pb36Ag2 and Sn60Pb40, suitable lead-free replacement. Contains eutectic Sn-In phase with melting point at 118 °C, avoid use above 100 °C.
In74Cd26 123[74]CdYes
In66.7Bi33.3 72.7
In61.7Bi30.8Cd7.5 62[75]CdYes
Bi47.5Pb25.4Sn12.6Cd9.5In5 57/65[76]Pb, CdNo
Bi48Pb25.4Sn12.8Cd9.6In4 61/65[77]Cd, PbNo
Bi49Pb18Sn15In18 58/69[78]PbNo
Bi49Pb18Sn12In21 58PbYesCerrolow 136. Slightly expands on cooling, later shows slight shrinkage in couple hours afterwards. Used as a solder in low-temperature physics.[28] Also the ChipQuik desoldering alloy.[79]
Bi50.5Pb27.8Sn12.4Cd9.3 70/73[80]Pb, CdNo
Bi50Pb26.7Sn13.3Cd10 70Pb, CdYesCerrobend. Used in low-temperature physics as a solder.[28]
Bi44.7Pb22.6In19.1Cd5.3Sn8.3 47Cd, PbYesCerrolow 117. Used as a solder in low-temperature physics.[28]
In60Sn40 113/122[5]–No
In51.0Bi32.5Sn16.5 60.5–YesField's metal
Bi49.5Pb27.3Sn13.1Cd10.1 70.9Cd, PbYesLipowitz Metal
Bi50.0Pb25.0Sn12.5Cd12.5 71Cd, PbYesWood's metal, mostly used for casting.
Bi50.0Pb31.2Sn18.8 97PbNoNewton's metal
Bi50Pb28Sn22 109PbNoRose's metal. It was used to secure cast iron railings and balusters in pockets in stone bases and steps. Does not contract on cooling.
Bi56Sn30In14 79/91NoChipQuik desoldering alloy, lead-free[81]
Cd95Ag5 338/393[82]CdNoKappTec General purpose solder that will join all solderable metals except Aluminum. High temperature, high strength solder. It is used in applications where alloys melting higher than soft solders are required, but the cost and strength of Silver-brazing alloys is not necessary.[82]
Cd82.5Zn17.5 265[83]CdYesMedium temperature alloy that provide strong, corrosion-resistant joints on most metals.[83] Also for soldering aluminium and die-cast zinc alloys.[13] Used in cryogenic physics for attaching electrical potential leads to specimens of metals, as this alloy does not become superconductive at liquid helium temperatures.[28]
Cd70Zn30 265/300[83]CdNoMedium temperature alloy that provide strong, corrosion-resistant joints on most metals. Works especially well on Aluminum-to-Aluminum and Aluminum-to-Copper joints, with excellent corrosion resistance and superior strength in high vibration and high stress applications in electronics, lighting and electrical products.[83]
Cd60Zn40 265/316[83]CdNoMedium temperature alloy that provide strong, corrosion-resistant joints on most metals. Works especially well on Aluminum-to-Aluminum and Aluminum-to-Copper joints, with excellent corrosion resistance and superior strength in high vibration and high stress applications in electronics, lighting and electrical products.[83]
Cd78Zn17Ag5 249/316[84]CdNoKappTecZ High temperature, high strength solder that may be used on most metals, but works extremely well on Aluminum, Copper and Stainless Steel. It has a high tolerance to vibration and stress, and good elongation for use on dissimilar metals. Above its liquidus of 600 °F, this solder is extremely fluid and will penetrate the closest joints.[84]
Sn40Zn27Cd33 176/260[85]CdNoKappRad[85] Developed specifically to join and repair Aluminum and Aluminum/Copper radiators and heat exchangers. A lower melting point makes delicate repair work easier.[85]
Zn90Cd10 265/399CdFor soldering aluminium. Good wetting.[52]
Zn60Cd40 265/335CdFor soldering aluminium. Very good wetting.[52]
Cd70Sn30 140/160[6]CdNoCd70, thermal-free solder. Produces low thermal EMF joints in copper, does not form parasitic thermocouples. Used in low-temperature physics.[28]
Sn50Pb32Cd18 145[6]Cd, PbCd18
Sn40Pb42Cd18 145[86]Cd, PbLow melting temperature allows repairing pewter and zinc objects, including die-cast toys.
Zn70Sn30 199/376–NoFor soldering aluminium. Excellent wetting.[35] Good strength.
Zn60Sn40 199/341–NoFor soldering aluminium. Good wetting.[52]
Zn95Sn5 382–yes?For soldering aluminium. Excellent wetting.[35]
Sn90Au10 217[87]–Yes
Au80Sn20 280–YesAu80. Good wetting, high strength, low creep, high corrosion resistance, high thermal conductivity, high surface tension, zero wetting angle. Suitable for step soldering. The original flux-less alloy, does not need flux. Used for die attachment and attachment of metal lids to semiconductor packages, e.g. kovar lids to ceramic chip carriers. Coefficient of expansion matching many common materials. Due to zero wetting angle requires pressure to form a void-free joint. Alloy of choice for joining gold-plated and gold-alloy plated surfaces. As some gold dissolves from the surfaces during soldering and moves the composition to non-eutectic state (1% increase of Au content can increase melting point by 30 °C), subsequent desoldering requires higher temperature.[88] Forms a mixture of two brittle intermetallic phases, AuSn and Au5Sn.[89] Brittle. Proper wetting achieved usually by using nickel surfaces with gold layer on top on both sides of the joint. Comprehensively tested through military standard environmental conditioning. Good long-term electrical performance, history of reliability.[26] One of the best materials for soldering in optoelectronic devices and components packaging.[90] Low vapor pressure, suitable for vacuum work. Generally used in applications that require a melting temperature over 150 °C.[91] Good ductility. Also classified as a braze.
Au98Si2 370/800[6]–Au98. A non-eutectic alloy used for die attachment of silicon dies. Ultrasonic assistance is needed to scrub the chip surface so a eutectic (3.1% Si) is reached at reflow.
Au96.8Si3.2 370[6] 363[92]–YesAu97.[88] AuSi3.2 is a eutectic with melting point of 363 °C. AuSi forms a meniscus at the edge of the chip, unlike AuSn, as AuSi reacts with the chip surface. Forms a composite material structure of submicron silicon plates in soft gold matrix. Tough, slow crack propagation.[45]
Au87.5Ge12.5 361 356[6]–YesAu88. Used for die attachment of some chips.[5] The high temperature may be detrimental to the chips and limits reworkability.[26]
Au82In18 451/485[6]–NoAu82. High-temperature, extremely hard, very stiff.
In100 157–PureIn99. Used for die attachment of some chips. More suitable for soldering gold, dissolution rate of gold is 17 times slower than in tin-based solders and up to 20% of gold can be tolerated without significant embrittlement. Good performance at cryogenic temperatures.[93] Wets many surfaces incl. quartz, glass, and many ceramics. Deforms indefinitely under load. Does not become brittle even at low temperatures. Used as a solder in low-temperature physics, will bond to aluminium. Can be used for soldering to thin metal films or glass with an ultrasonic soldering iron.[28]
Sn90.7Ag3.6Cu0.7Cr5 217/1050[94]–NoC-Solder. Lead-free, low-temperature soldering alloy for joining of various carbon materials including carbon fibres and carbon nanotube fibres in both carbon-carbon and carbon-metal arrangements. Produces mechanically strong and electrically conductive bonds. Provides wetting of carbon[95] and other materials generally considered as difficult to solder, including aluminium, stainless steel, titanium, glass, and ceramics.

Notes on the above table

In the Sn-Pb alloys, tensile strength increases with increasing tin content. Indium-tin alloys with high indium content have very low tensile strength.[5]

For soldering semiconductor materials, e.g. die attachment of silicon, germanium and gallium arsenide, it is important that the solder contains no impurities that could cause doping in the wrong direction. For soldering n-type semiconductors, solder may be doped with antimony; indium may be added for soldering p-type semiconductors. Pure tin can also be used.[35][96]

Various fusible alloys can be used as solders with very low melting points; examples include Field's metal, Lipowitz's alloy, Wood's metal, and Rose's metal.

Properties

The thermal conductivity of common solders ranges from 30 to 400 W/(m·K), and the density from 9.25 to 15.00 g/cm3.[97][98]

Material Thermal conductivity[98]
(W/m·K)		 Melting point[98]
(°C)
Sn-37Pb (eutectic)50.9183
Sn-0.7Cu53[1]227
Sn-2.8Ag-20.0In53.5175–186
Sn-2.5Ag-0.8Cu-0.5Sb57.26215–217
Pb-5Sn63310
Lead (Pb)35.0327.3
Tin (Sn)73.0231.9
Aluminum (Al)240660.1
Copper (Cu)393–4011083
FR-41.7

References
  1. Meng Zhao, Liang Zhang, Zhi-Quan Liu, Ming-Yue Xiong, and Lei Sun (2019). "Structure and properties of Sn-Cu lead-free solders in electronics packaging". Science and Technology of Advanced Materials. 20 (1): 421–444. doi:10.1080/14686996.2019.1591168. PMC 6711112. PMID 31489052.CS1 maint: multiple names: authors list (link)
  2. "Galvanite". Kapp Alloy & Wire, Inc. Retrieved 23 October 2012.
  3. "KappFree". Kapp Alloy & Wire, Inc. Retrieved 2 March 2015.
  4. Kapp Alloy. "Kapp Eco Babbitt". Retrieved 4 April 2013.
  5. Charles A. Harper (2003). Electronic materials and processes. McGraw-Hill Professional. pp. 5–8. ISBN 978-0-07-140214-9.
  6. "Alloy information" (PDF). smarttec.de. Retrieved 27 March 2018.
  7. Sanka Ganesan; Michael Pecht (2006). Lead-free electronics. Wiley. p. 110. ISBN 978-0-471-78617-7.
  8. Ray P. Prasad (1997). Surface mount technology: principles and practice. Springer. p. 385. ISBN 978-0-412-12921-6.
  9. SOLDER ALLOYS Selection Chart. (PDF). Retrieved 2010-07-06.
  10. Walt Kester James Bryant Walt Jung Scott Wurcer Chuck Kitchin (2005). "Ch. 4. Sensor Signal Conditioning" (PDF). Op Amp Applications Handbook. Newnes/Elsevier. p. 4.49. ISBN 0-7506-7844-5.
  11. T R Barnard (1959). "Winding Ropes and Guide Ropes". Mechanical Engineering. Coal Mining Series (2nd ed.). London: Virtue. pp. 374–375.
  12. Madara Ogot; Gul Okudan-Kremer (2004). Engineering design: a practical guide. p. 445. ISBN 978-1-4120-3850-8.
  13. Kaushish (2008). Manufacturing Processes. PHI Learning Pvt. Ltd. p. 378. ISBN 978-81-203-3352-9.
  14. "Kapp GalvRepair". Kapp Alloy & Wire, Inc. Retrieved 23 October 2012.
  15. Howard H. Manko (2001). Solders and soldering: materials, design, production, and analysis for reliable bonding. McGraw-Hill Professional. p. 164. ISBN 978-0-07-134417-3.
  16. 3439-00-577-7594 Solder, Tin Alloy. Tpub.com. Retrieved 2010-07-06.
  17. Properties of Solders. farnell.com.
  18. Pajky_vkladanylist_Cze_ang_2010.indd. (PDF). Retrieved 2010-07-06.
  19. "Balve Zinn Solder Sn63Pb37 – Balver Zinn" (PDF). Retrieved 20 July 2016.
  20. "Balver Zinn Solder Sn63PbP" (PDF). balverzinn.com. Retrieved 27 March 2018.
  21. John H. Lau (1991). Solder joint reliability: theory and applications. Springer. p. 178. ISBN 978-0-442-00260-2.
  22. "Indium Corp. Indalloy® 228 Pb-Sn-Ag Solder Alloy". Retrieved 20 July 2016.
  23. "Indium Corp. Indalloy® 290 In-Ag Solder Alloy". Retrieved 20 July 2016.
  24. "Indium Corp. Indalloy® 3 In-Ag Solder Alloy". Retrieved 20 July 2016.
  25. "Indium Corp. Indalloy® 204 In-Pb Solder Alloy". Retrieved 20 July 2016.
  26. Merrill L. Minges (1989). Electronic Materials Handbook: Packaging. ASM International. p. 758. ISBN 978-0-87170-285-2.
  27. "Indium Corp. Indalloy 1 Indium-Tin Solder Alloy". Retrieved 20 July 2016.
  28. Guy Kendall White; Philip J. Meeson (2002). Experimental techniques in low-temperature physics. Clarendon. pp. 207–. ISBN 978-0-19-851428-2. Retrieved 14 May 2011.
  29. "Indium Corp. Indalloy 13 Indium Solder Alloy". Retrieved 20 July 2016.
  30. "Indium Corp. Indalloy® 10 Pb-In Solder Alloy". Retrieved 20 July 2016.
  31. "Indium Corp. Indalloy® 9 Sn-Pb-In Solder Alloy". Retrieved 20 July 2016.
  32. "94.5Pb-5.5Ag Lead-Silver Solder, ASTM Class 5.5S; UNS L50180". Retrieved 20 July 2016.
  33. "Indium Corp. Indalloy 175 Lead Solder Alloy". Retrieved 20 July 2016.
  34. "97.5Pb-2.5Ag Lead-Silver Solder, ASTM Class 2.5S UNS L50132". Retrieved 20 July 2016.
  35. Symposium on Solder. ASTM International. 1957. p. 114.
  36. "Balver Zinn Solder SN97C (SnAg3.0Cu0.5)" (PDF). balverzinn.com. Retrieved 27 March 2018.
  37. Karl Seelig (2017) New Pb-Free Solder Alloy for Demanding Applications. VP Technology, AIM Solder
  38. "Balver Zinn Solder SN96C (SnAg3,8Cu0,7)" (PDF). balverzinn.com. Retrieved 27 March 2018.
  39. "Indium Corp. Indalloy® 252 95.5Sn/3.9Ag/0.6Cu Lead-Free Solder Alloy". Retrieved 20 July 2016.
  40. "Indium Corp. Indalloy® 246 95.5Sn/4.0Ag/0.5Cu Lead-Free Solder Alloy". Retrieved 20 July 2016.
  41. Karl J. Puttlitz; Kathleen A. Stalter (2004). Handbook of lead-free solder technology for microelectronic assemblies. CRC Press. p. 541. ISBN 978-0-8247-4870-8.
  42. "Solder selection for photonic packaging". AIM Metals & Alloys. Retrieved 20 August 2016.
  43. "KappZapp". Kapp Alloy & Wire, Inc. Retrieved 25 October 2012.
  44. "KappZapp7". SolderDirect.com. Retrieved 25 October 2012.
  45. Sanka Ganesan; Michael Pecht (2006). Lead-free electronics. Wiley. p. 404. ISBN 978-0-471-78617-7.
  46. Keith William Sweatman and Tetsuro Nishimura (January 2006). "The Fluidity of the Ni-Modified Sn-Cu Eutectic Lead-Free Solder" (PDF). Nihon Superior Co., Ltd.
  47. SN100C® LEAD-FREE SOLDER ALLOY. aimsolder.com
  48. K100LD. kester.com
  49. SN100C® Technical Guide. floridacirtech.com
  50. "Balver Zinn Solder SCA (SnCu0.7Ag0.3)" (PDF). balverzinn.com. Retrieved 27 March 2018.
  51. Balver Zinn Solder Sn97Cu3 Archived 2011-07-07 at the Wayback Machine
  52. Howard H. Manko (2001). Solders and soldering: materials, design, production, and analysis for reliable bonding. McGraw-Hill Professional. pp. 396–. ISBN 978-0-07-134417-3.
  53. "KappAloy". Kapp Alloy & Wire, Inc. Retrieved 23 October 2012.
  54. "Indium Corp. Indalloy® 249 91.8Sn/3.4Ag/4.8Bi Lead-Free Solder Alloy". Retrieved 20 July 2016.
  55. Paul T. Vianco and Jerome A. Rejent (1994) "Tin-silver-bismuth solders for electronics assembly " U.S. Patent 5,439,639
  56. George P Luckey (1920) U.S. Patent 1,333,666
  57. Composition And Physical Properties Of Alloys Archived 2012-04-26 at the Wayback Machine. Csudh.edu (2007-08-18). Retrieved 2010-07-06.
  58. Karl J. Puttlitz; Kathleen A. Stalter (2004). Handbook of lead-free solder technology for microelectronic assemblies. CRC Press. ISBN 978-0-8247-4870-8.
  59. "Indium Corp. Indalloy 226 Tin Solder Alloy". Retrieved 20 July 2016.
  60. Laurence G. Stevens and Charles E. T. White (1992) "Lead-free alloy containing tin, zinc and indium" U.S. Patent 5,242,658
  61. "Indium Corp. Indalloy® 231 Sn-Zn-In-Bi Solder Alloy". Retrieved 20 July 2016.
  62. "Indium Corp. Indalloy® 254 86.9Sn/10.0In/3.1Ag Lead-Free Solder Alloy". Retrieved 20 July 2016.
  63. "Indium Corp. Indalloy® 131 97Sn/3Sb Lead-Free Solder Alloy". Retrieved 20 July 2016.
  64. "Indium Corp. Indalloy® 129 99Sn/1Sb Lead-Free Solder Alloy". Retrieved 20 July 2016.
  65. "Indium Corp. Indalloy® 282 57Bi/42Sn/1Ag Lead-Free Solder Alloy". Retrieved 20 July 2016.
  66. "Indium Corp. Indalloy® 281 Bi-Sn Solder Alloy". Retrieved 20 July 2016.
  67. "Indium Corp. Indalloy 67 Bismuth-Lead Solder Alloy". Retrieved 20 July 2016.
  68. "Indium Corp. Indalloy® 2 In-Pb-Ag Solder Alloy". Retrieved 20 July 2016.
  69. "Indium Corp. Indalloy 532 Tin Solder Alloy". Retrieved 20 July 2016.
  70. "Indium Corp. Indalloy® 150 Pb-In Solder Alloy". Retrieved 20 July 2016.
  71. "Indium Corp. Indalloy 87 Indium-Tin Solder Alloy". Retrieved 20 July 2016.
  72. "Indium Corp. Indalloy® 181 Sn-Pb-Cd Solder Alloy". Retrieved 20 July 2016.
  73. "Indium Corp. Indalloy® 227 Sn-In-Ag Solder Alloy". Retrieved 20 July 2016.
  74. "Indium Corp. Indalloy 253 Indium Solder Alloy". Retrieved 20 July 2016.
  75. "Indium Corp. Indalloy 18 Indium Solder Alloy". Retrieved 20 July 2016.
  76. "Indium Corp. Indalloy 140 Bismuth Solder Alloy". Retrieved 20 July 2016.
  77. "Indium Corp. Indalloy 147 Bismuth Solder Alloy". Retrieved 20 July 2016.
  78. "Indium Corp. Indalloy 21 Bismuth Solder Alloy". Retrieved 20 July 2016.
  79. Johnson Manufacturing Co, MSDS for Chip Quik Alloy w/Lead. Retrieved on February 6, 2015.
  80. "Indium Corp. Indalloy 22 Bismuth Solder Alloy". Retrieved 20 July 2016.
  81. "Chip Quik – SMD Removal Kit (Chip Quik Alloy 2.5ft, flux, alcohol pads) lead-free". Retrieved 20 July 2016.
  82. "KappTec". Kapp Alloy & Wire, Inc. Retrieved 23 October 2012.
  83. "Kapp Cad/Zinc". Kapp Alloy & Wire, Inc. Retrieved 23 October 2012.
  84. "KappTecZ". Kapp Alloy & Wire, Inc. Retrieved 25 October 2012.
  85. "KappRad". Kapp Alloy & Wire, Inc. Retrieved 25 October 2012.
  86. Soft Solders. www.cupalloys.co.uk (2009-01-20). Retrieved 2010-07-06.
  87. "Indium Corp. Indalloy® 238 Sn-Au Solder Alloy". Retrieved 20 July 2016.
  88. http://www.quadsimia.com/, Quadsimia Internet Solutions -. "Indium Corporation Global Solder Supplier Electronics Assembly Materials". Indium Corporation. Retrieved 27 March 2018.
  89. "Chip Scale Review Magazine". Chipscalereview.com. 2004-04-20. Retrieved 2010-03-31.
  90. "Au/Sn Solder Alloy and Its Applications in Electronics Packaging". ametek-ecp.com. Retrieved 27 March 2018.
  91. "High-Temperature Gold Solder & Braze Materials" (PDF). Indium Corporation. Retrieved 27 March 2018.
  92. "Indium Corp. Indalloy 184 Gold Solder Alloy". Retrieved 20 July 2016.
  93. T.Q. Collier (May–Jun 2008). "Choosing the best bumb for the buck". Advanced Packaging. 17 (4): 24. ISSN 1065-0555.
  94. M. Burda; et al. (2015). "Soldering of carbon materials using transition metal rich alloys". ACS Nano. 9 (8): 8099–107. doi:10.1021/acsnano.5b02176. PMID 26256042.
  95. "Technical Data Sheet, Cametics C-Solder active soldering alloy" (PDF). cametics.com. Retrieved 27 March 2018.
  96. Nan Jiang (2019). "Reliability issues of lead-free solder joints in electronic devices". Science and Technology of Advanced Materials. 20 (1): 876–901. doi:10.1080/14686996.2019.1640072. PMC 6735330. PMID 31528239.
  97. "Thermal Properties of Metals, Conductivity, Thermal Expansion, Specific Heat – Engineers Edge". Retrieved 20 July 2016.
  98. "Database for Solder Properties with Emphasis on New Lead-free Solders" (PDF). metallurgy.nist.gov. 2012-07-10. Retrieved 2013-06-08.
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