FabDigit

Precious Metal 88Ag-12SnO2

ASTM B735

88Ag-12SnO2 is a cadmium-free silver-tin oxide contact composite with roughly 12% SnO2 dispersed in a silver matrix, supplied to ASTM B735 in annealed, 1/2H, H, PM and internally oxidised (IO) conditions.

High cost $$$$

Reference datasheet — 88Ag-12SnO2 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.

Values for the H condition

88Ag-12SnO2 tempers and conditions

88Ag-12SnO2 is supplied in 4 conditions, soft to hard. H is the default FabDigit quotes; the values on this page are for it.

Compare all 4 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
soft (recrystallised, typ. 550–650 °C)
Pick for rivets, deep-drawn cups and contact tips that must be cold-headed, riveted or heavily formed.1502352067 HB80 % IACS
Half hard
Compromise condition for stamped contact strip that still needs moderate bending.2002701381 HB79 % IACS
pressed, sintered and repressed contact tips (as-sintered)
Net-shape sintered tips with slight residual porosity; chosen for large contactor contacts brazed to Cu carriers.220676 HB72 % IACS
HDefault
Hardened
Standard stock condition for AgSnO2 wire, profile and strip used to stamp or weld contact tips.250300895 HB78 % IACS

Supply forms, finishes and certifications

Ways 88Ag-12SnO2 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.

OptionWhat it isType
IO
Internally oxidisedSupply option

What is 88Ag-12SnO2?

88Ag-12SnO2 is a cadmium-free silver-tin oxide contact composite with roughly 12% SnO2 dispersed in a silver matrix, supplied to ASTM B735 in annealed, 1/2H, H, PM and internally oxidised (IO) conditions. The high oxide fraction gives good arc-erosion and anti-welding behaviour in contactors and breakers, and it is available as strip, wire, extruded profile and tips with a fine-silver backing layer for brazing. Conductivity is 78% IACS with 320 W/m·K, hardness 95 HB, tensile strength 300 MPa and modulus 88 GPa, with service to 250 °C. Elongation of only 8% limits cold forming; 90Ag-10SnO2 is the more ductile, higher-conductivity alternative. 88Ag-12SnO2 has a density of 9.9 g/cm³ (0.358 lb/in³), lighter than 70% of precious metal grades. It melts at 961°C (1,762 °F). 88Ag-12SnO2 has a yield strength of 250 MPa (36.3 ksi) and a tensile strength of 300 MPa (43.5 ksi) — stronger than 81% of precious metal grades. Elongation at break is 8% and the elastic modulus is 88 GPa (12.8 Msi).

What is 88Ag-12SnO2 used for?

  • contactors
  • circuit breakers
  • automotive relays

Advantages

  • High strength — 250 MPa (36.3 ksi), better than 81% of precious metal grades
  • Conducts heat well — 320 W/m·K (184.9 BTU/hr·ft·°F), better than 80% of precious metal grades
  • High electrical conductivity — 78 % IACS, better than 79% of precious metal grades

Limitations

  • Limited ductility — 8%, worse than 92% of precious metal grades
  • Limited formability — 35/100, worse than 92% of precious metal grades
  • Hard to polish — 65/100, worse than 87% of precious metal grades

88Ag-12SnO2 properties

Typical room-temperature values for 88Ag-12SnO2-H; bars are the position among precious metal grades.

Physical3

88Ag-12SnO2 has a density of 9.9 g/cm³ (0.358 lb/in³), lighter than 70% of precious metal grades. It melts at 961°C (1,762 °F).

Density9.9 g/cm³0.36 lb/in³
Melting Point (Solidus)961°C1,762 °F
Liquidus Temperature962°C1,764 °F

Mechanical9

88Ag-12SnO2 has a yield strength of 250 MPa (36.3 ksi) and a tensile strength of 300 MPa (43.5 ksi) — stronger than 81% of precious metal grades. Elongation at break is 8% and the elastic modulus is 88 GPa (12.8 Msi).

Elastic (Young's) Modulus88 GPa12.8 Msi
Shear Modulus32 GPa4.6 Msi
Bulk Modulus105 GPa15.2 Msi
Poisson's Ratio0.36
Tensile Strength (Ultimate)300 MPa43.5 ksi
Yield Strength (0.2% offset)250 MPa36.3 ksi
Elongation at Break8%
Hardness, Brinell95 HB
Hardness, Vickers100 HV

Thermal6

88Ag-12SnO2 is rated for continuous service to 250°C (482 °F). It conducts heat at 320 W/m·K (184.9 BTU/hr·ft·°F), better than 80% of precious metal grades. Thermal expansion is 18 µm/m·K (10 µin/in·°F).

Thermal Conductivity320 W/m·K185 BTU/hr·ft·°F
Specific Heat Capacity240 J/kg·K0.06 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)18 µm/m·K10 µin/in·°F
Latent Heat of Fusion92 J/g39.6 BTU/lb
Max Service Temperature (continuous)250°C482 °F
Min Service Temperature-60°C-76 °F

Electrical3

88Ag-12SnO2 conducts electricity at 78 % IACS, better than 79% of precious metal grades.

Electrical Conductivity78 % IACS
Electrical Resistivity2.2×10⁻⁸ Ω·m0.866 µΩ·in
Magnetic Responsenon-magnetic

Chemical & Environmental3

Corrosion resistance is very good (80/100), worse than 52% of precious metal grades.

Galvanic Potential (seawater, vs SCE)0.05 V
Corrosion ResistanceVery good80/100
Chemical Resistance SummaryDoes not oxidise in air; resistant to alkalis and most organics. Tarnishes (Ag2S) in H2S/sulfur atmospheres and darkens in ozone; attacked by nitric acid, hot sulfuric acid, halogens and ammonia-cyanide solutions.

Sustainability4

Producing a kilogram of 88Ag-12SnO2 takes about 1,300 MJ of energy and emits 100 kg of CO₂ — less than 61% of precious metal grades. Typical recycled content is 40%.

Embodied Energy (primary production)1,300 MJ/kg558,900 BTU/lb
Embodied Carbon (primary production)100 kg CO₂/kg
Embodied Water400 L/kg47.9 gal/lb
Typical Recycled Content40%

Manufacturability8

88Ag-12SnO2's machinability is fair (40/100, worse than 60% of precious metal grades); weldability good (55/100); formability fair (35/100).

MachinabilityFair40/100
Machinability Rating (AISI 1212 = 100 %)35%
WeldabilityGood55/100
Formability (cold)Fair35/100
CastabilityPoor25/100
Brazeability / SolderabilityExcellent85/100
PolishabilityGood65/100
Anodizing Responsen/a — silver-based composite; contacts are used bare or with a fine-silver/Ag-braze backing layer

Common Calculations5

Specific Strength (UTS / density)calculated30 kN·m/kg
Specific Stiffness (E / density)calculated8.9 MN·m/kg
Modulus of Resiliencecalculated355 kJ/m³
Thermal Diffusivitycalculated134.7 mm²/s
Thermal Shock Resistance Indexcalculated61

Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.

Strength versus weight in the precious metal family

Yield strength against density for every precious metal grade FabDigit runs. 88Ag-12SnO2 is highlighted; hover a dot for its name, or open the interactive family chart.

50100200500101520Density (g/cm³)Yield strength (MPa) — log scale88Ag-12SnO2

Working with 88Ag-12SnO2

Is 88Ag-12SnO2 easy to machine?

Turns and stamps like soft silver but is gummy and the SnO2 is mildly abrasive — use sharp carbide/PCD tools, high speed, light feed and oil mist; keep all chips for refining.

Can 88Ag-12SnO2 be welded?

Not fusion welded as a structural alloy; tips are resistance-welded, laser-welded or Ag-brazed (BAg-1/Cd-free) to Cu or CuZn carriers, often through a fine-silver backing layer.

Can 88Ag-12SnO2 be formed, bent or molded?

Supplied hot-extruded then cold drawn/rolled; anneal at ~550–650 °C before cold heading, riveting or deep drawing, and expect lower cold ductility than AgCdO or AgNi.

88Ag-12SnO2 chemical composition (wt %)

Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.

ElementSpec limit (wt %)Nominal
SnO2tin(IV) oxide dispersoid, ≈17 vol%11 – 1312
In2O3optional wetting/dopant additive in some grades (also Bi2O3, WO3, CuO, MoO3)0 – 1
CdRoHS-relevant residual; grade is cadmium-free by definition0 – 0.01
Agnominal 88 %, purity of matrix ≥99.9 %balance

What surface finishes work on 88Ag-12SnO2?

Used bare — the arc keeps the surface clean; do not plate the contact face. Ag or Ag-braze backing improves solderability; degrease and store away from H2S to limit tarnish.

Equivalent designations

Standards and trade names that resolve to Precious Metal 88Ag-12SnO2 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.

ASTM
B735
Also called
AgSnO2-12

How much does 88Ag-12SnO2 cost?

88Ag-12SnO2 is a high-cost precious metal ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.

88Ag-12SnO2 — frequently asked

What is 88Ag-12SnO2 used for?

88Ag-12SnO2 is typically used for contactors, circuit breakers and automotive relays. In short: cadmium-free AgCdO replacement; best arc-erosion AgSnO2; low cold ductility.

What is the yield strength of 88Ag-12SnO2?

88Ag-12SnO2 has a typical yield strength of 250 MPa (36.3 ksi) and a tensile strength of 300 MPa (43.5 ksi) — stronger than 81% of precious metal grades. Strength varies by condition: see the 4 listed tempers.

Is 88Ag-12SnO2 easy to machine?

Not especially — machinability is rated fair (40/100, worse than 60% of precious metal grades). Turns and stamps like soft silver but is gummy and the SnO2 is mildly abrasive — use sharp carbide/PCD tools, high speed, light feed and oil mist; keep all chips for refining.

Can 88Ag-12SnO2 be welded?

Yes — weldability is rated good (55/100). Not fusion welded as a structural alloy; tips are resistance-welded, laser-welded or Ag-brazed (BAg-1/Cd-free) to Cu or CuZn carriers, often through a fine-silver backing layer.

What surface finishes work on 88Ag-12SnO2?

Used bare — the arc keeps the surface clean; do not plate the contact face. Ag or Ag-braze backing improves solderability; degrease and store away from H2S to limit tarnish.

Can 88Ag-12SnO2 be formed, bent or molded?

Supplied hot-extruded then cold drawn/rolled; anneal at ~550–650 °C before cold heading, riveting or deep drawing, and expect lower cold ductility than AgCdO or AgNi.

What is the maximum service temperature of 88Ag-12SnO2?

88Ag-12SnO2 is rated for continuous use to about 250°C (482 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

How much does 88Ag-12SnO2 cost?

88Ag-12SnO2 is a high-cost precious metal ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.

Sources

  1. Data Book of Electrical Contacts (AgSnO2 contact materials) — Doduco / AMI Doduco (2012)
  2. ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials (Electrical Contact Materials) — ASM International (1990)
  3. Silver tin oxide contact material datasheets (AgSnO2 10/12/14) — Metalor / Umicore / Materion (2022)
  4. IEC 60947-4-1 contactor duty and contact material practice — IEC (2018)

Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.