Precious Metal AgSnO2In2O3 90/10 EXT
Grade · default condition
The everyday balance of arc erosion resistance, conductivity and workability for relay and contactor tips.
Values for the 90/10 EXT condition
Other AgSnO2In2O3 tempers and conditions
AgSnO2In2O3 is listed in 6 conditions; see the grade overview at AgSnO2In2O3.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AgSnO2In2O3 90/10 | Use for riveting, heavy upsetting or cold forming of tips where ductility is needed before final work hardening. | 110 | 210 | 20 | 66 HB | 68 % IACS |
P/M pressed–sintered–repressed compact | Net-shape sintered tips for larger contactor blocks where extrusion of a billet is uneconomic. | 170 | 240 | 6 | 80 HB | 62 % IACS |
AgSnO2In2O3 92/8 | Choose for low contact resistance and low temperature rise in small relays with moderate arcing duty. | 180 | 255 | 12 | 82 HV | 72 % IACS |
90/10 EXTDefaultThis page AgSnO2In2O3 90/10 | The everyday balance of arc erosion resistance, conductivity and workability for relay and contactor tips. | 205 | 280 | 9 | 95 HV | 66 % IACS |
AgSnO2In2O3 88/12 | Pick when weld resistance and erosion life under high make currents matter more than temperature rise. | 225 | 300 | 7 | 105 HV | 60 % IACS |
AgSnO2In2O3 | Internally oxidised route gives an ultrafine oxide dispersion, higher hardness and lower contact resistance for demanding AC contactors. | 240 | 310 | 6 | 104 HB | 68 % IACS |
What is AgSnO2In2O3 90/10 EXT?
AgSnO2In2O3 90/10 EXT is AgSnO2In2O3 in the 90/10 EXT grade — the everyday balance of arc erosion resistance, conductivity and workability for relay and contactor tips. AgSnO2In2O3 90/10 EXT has a yield strength of 205 MPa (29.7 ksi) and a tensile strength of 280 MPa (40.6 ksi) — stronger than 57% of precious metal grades. Elongation at break is 9% and the elastic modulus is 88 GPa (12.8 Msi). AgSnO2In2O3 90/10 EXT has a density of 9.95 g/cm³ (0.359 lb/in³), lighter than 67% of precious metal grades. It melts at 960°C (1,760 °F).
Advantages
- Conducts heat well — 320 W/m·K (184.9 BTU/hr·ft·°F), better than 80% of precious metal grades
Limitations
- Hard to polish — 60/100, worse than 92% of precious metal grades
- Limited ductility — 9%, worse than 91% of precious metal grades
- Limited formability — 45/100, worse than 91% of precious metal grades
AgSnO2In2O3 90/10 EXT properties
Typical room-temperature values for AgSnO2In2O3 90/10 EXT; 11 are specific to this condition. Other listed values are AgSnO2In2O3 reference data and may not represent this condition. Bars are the position among precious metal grades.
Physical3
AgSnO2In2O3 90/10 EXT has a density of 9.95 g/cm³ (0.359 lb/in³), lighter than 67% of precious metal grades. It melts at 960°C (1,760 °F).
Mechanical10
AgSnO2In2O3 90/10 EXT has a yield strength of 205 MPa (29.7 ksi) and a tensile strength of 280 MPa (40.6 ksi) — stronger than 57% of precious metal grades. Elongation at break is 9% and the elastic modulus is 88 GPa (12.8 Msi).
Thermal6
AgSnO2In2O3 90/10 EXT 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 17.5 µm/m·K (9.72 µin/in·°F).
Electrical3
AgSnO2In2O3 90/10 EXT conducts electricity at 66 % IACS, better than 74% of precious metal grades.
Chemical & Environmental3
Corrosion resistance is excellent (85/100), better than 61% of precious metal grades.
Sustainability4
Producing a kilogram of AgSnO2In2O3 90/10 EXT takes about 1,500 MJ of energy and emits 130 kg of CO₂ — more than 51% of precious metal grades. Typical recycled content is 40%.
Manufacturability6
AgSnO2In2O3 90/10 EXT's machinability is fair (40/100, worse than 60% of precious metal grades); weldability poor (30/100); formability fair (45/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with AgSnO2In2O3 90/10 EXT
Is AgSnO2In2O3 easy to machine?
Machinable with sharp carbide or PCD tooling and generous coolant; the SnO2/In2O3 dispersion is abrasive while the Ag matrix smears, so light finishing cuts and frequent edge changes are needed.
Can AgSnO2In2O3 be welded?
Not fusion welded — tips are resistance-welded or induction/torch brazed through a fine-silver or AgCu backing layer using Ag-Cu-P or BAg filler at low heat input.
Can AgSnO2In2O3 be formed, bent or molded?
Supplied as extruded wire/strip from sintered billets; cold heading, upsetting and profile rolling are routine, but deep drawing and sharp bends are limited by the low elongation of high-oxide grades.
What surface finishes work on AgSnO2In2O3?
Used bare; contact faces are coined or turned rather than plated, and any tarnish film is normally cleared by the first arcing operations.
AgSnO2In2O3 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.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| SnO2dispersed oxide phase; 8 wt% for the 90/10 default | 6 – 13 | 8 |
| In2O3wetting/sintering modifier, sometimes with traces of Bi2O3 or CuO | 1 – 4 | 2 |
| Ag≥ 99.95 % purity silver matrix | balance | — |
AgSnO2In2O3 90/10 EXT — frequently asked
What is AgSnO2In2O3 90/10 EXT used for?
AgSnO2In2O3 90/10 EXT is typically used for automotive relays, low-voltage circuit breakers, contactors and AC/DC power relays. In short: cadmium-free Ag-CdO replacement; low contact resistance oxide grade; abrasive to cutting tools.
What is the yield strength of AgSnO2In2O3 90/10 EXT?
AgSnO2In2O3 90/10 EXT has a typical yield strength of 205 MPa (29.7 ksi) and a tensile strength of 280 MPa (40.6 ksi) — stronger than 57% of precious metal grades. Strength varies by condition: see the 6 listed tempers.
Is AgSnO2In2O3 90/10 EXT easy to machine?
Not especially — machinability is rated fair (40/100, worse than 60% of precious metal grades). Machinable with sharp carbide or PCD tooling and generous coolant; the SnO2/In2O3 dispersion is abrasive while the Ag matrix smears, so light finishing cuts and frequent edge changes are needed.
Can AgSnO2In2O3 90/10 EXT be welded?
Not readily — weldability is rated poor (30/100). Not fusion welded — tips are resistance-welded or induction/torch brazed through a fine-silver or AgCu backing layer using Ag-Cu-P or BAg filler at low heat input.
What surface finishes work on AgSnO2In2O3 90/10 EXT?
Used bare; contact faces are coined or turned rather than plated, and any tarnish film is normally cleared by the first arcing operations.
Can AgSnO2In2O3 90/10 EXT be formed, bent or molded?
Supplied as extruded wire/strip from sintered billets; cold heading, upsetting and profile rolling are routine, but deep drawing and sharp bends are limited by the low elongation of high-oxide grades.
What is the maximum service temperature of AgSnO2In2O3 90/10 EXT?
AgSnO2In2O3 90/10 EXT 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.
What is the difference between AgSnO2In2O3 90/10 EXT and AgSnO2In2O3-IO?
90/10 EXT is the default condition — the everyday balance of arc erosion resistance, conductivity and workability for relay and contactor tips. IO: internally oxidised route gives an ultrafine oxide dispersion, higher hardness and lower contact resistance for demanding AC contactors. Yield strength is 205 MPa in 90/10 EXT versus 240 MPa in IO.
Sources
- Data Book of Electrical Contacts — DODUCO / AMI Doduco (2012)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials (electrical contact materials) — ASM International (1990)
- Silver metal oxide contact materials product data — Metalor Technologies (2022)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.