Sterling Silver 925
Mat Grades internal verification confirms source-backed fidelity and data integrity. It does not constitute external certification or guaranteed lot conformity. Read engineering disclaimer →
Key Engineering Properties
Representative source rows, qualified by their reported conditions. Inspect the tables below for all values, limits, and source notes.
Engineering Summary
Sterling Silver 925 is the preeminent global silver engineering alloy, containing a minimum of 92.50% silver alloyed with 7.50% copper. The copper addition creates an alpha + beta two-phase microstructure that more than doubles the yield strength and hardness of pure silver while preserving exceptional electrical conductivity (84% IACS) and thermal conductivity (410 W/(m·K)). Uniquely among common precious metal alloys, Sterling Silver is heat-treatable and precipitation hardenable.
Sterling Silver 925 Documented Applications
- ›Precision sliding electrical switchgear and relay contacts
- ›Acoustic instrument bodies (professional flutes, brass instrument bell liners)
- ›High-reliability multi-pin electronic connector shells and spring pins
- ›Precision surgical instruments requiring antimicrobial properties and rigidity
- ›Heavy-duty flatware, holloware, and high-wear decorative engineering assemblies
Recognized Aliases
Source-backed commercial trade name and short designations cataloged in canonical data.
Sterling Silver 925 Specifications & Designations
Standard Designations & Applicable Specifications — Semantically classified designations distinguishing primary standard identifiers, commercial trade names, and applicable specification references.
| System | Identifier | Standard System Name | Classification Notes & Provenance |
|---|---|---|---|
| UNSPRIMARY | P07925 | Unified Numbering System | —Ref: Standard Specifications for Silver & Silver Alloys (ASTM B742, ASTM B413, ISO 9202, DIN 17510) |
| ISO | Ag925 | International Organization for Standardization | —Ref: Standard Specifications for Silver & Silver Alloys (ASTM B742, ASTM B413, ISO 9202, DIN 17510) |
| ASTM | B742 Grade 92.5 | ASTM International | —Ref: Standard Specifications for Silver & Silver Alloys (ASTM B742, ASTM B413, ISO 9202, DIN 17510) |
| DIN | Ag925 | Deutsches Institut für Normung | —Ref: Standard Specifications for Silver & Silver Alloys (ASTM B742, ASTM B413, ISO 9202, DIN 17510) |
| W-Nr | 2.1213 | Werkstoffnummer | —Ref: Standard Specifications for Silver & Silver Alloys (ASTM B742, ASTM B413, ISO 9202, DIN 17510) |
| UK-HALLMARK | 925 | UK Hallmarking Act Fineness Mark | —Ref: Standard Specifications for Silver & Silver Alloys (ASTM B742, ASTM B413, ISO 9202, DIN 17510) |
| Recognized Name / Alias | Classification | Technical Usage & Context |
|---|---|---|
| Sterling Silver | Commercial Alias | Colloquial or commercial industry synonym |
| 925 Silver | Colloquial Alias | Colloquial or commercial industry synonym |
| Standard Silver | Historical Alias | Colloquial or commercial industry synonym |
| UNS P07925 | Commercial Alias | Colloquial or commercial industry synonym |
| Standards Body | Specification Code | Specification Title / Scope | Relationship Type |
|---|---|---|---|
| ASTM | ASTM B742 / B742M | Standard Specification for Fine Silver Electrical Contact Material (Grade 92.5) | Specification Reference |
| ISO | ISO 9202 | Jewellery and precious metals — Fineness of precious metal alloys | Specification Reference |
| DIN | DIN 17510 | Feinsilber und Silberlegierungen (Fine silver and silver alloys) | Specification Reference |
| UK-STATUTE | British Hallmarking Act 1973 | Hallmarking Act 1973 (Schedule 2 Standards of Fineness - Sterling Silver) | Specification Reference |
| ASTM | ASTM B742 Standard Specification for Fine Silver Contact Material (Grade 92.5) | Applicable specification reference. | Specification Reference |
Sterling Silver 925 Chemical Composition
Chemical Composition (Weight %) — Elemental limits and values from the cited source. Preserves exact semantic limits (minimums, maximums, and ranges).
| Element | Symbol | Atomic No. | Semantic Basis | Specified Value | Unit | Metallurgical Notes & Qualification | Data Status |
|---|---|---|---|---|---|---|---|
| Silver | Ag | 47 | MINIMUM | ≥ 92.50 | wt% | Ref: ASTM International & ISO / DIN Standards Technical Committees | VERIFIED |
| Copper | Cu | 29 | RANGE | 7.20 – 7.50 | wt% | Ref: ASTM International & ISO / DIN Standards Technical Committees | VERIFIED |
Sterling Silver 925 Physical Properties
Source-specific physical properties. Test temperatures are shown only where reported.
| Property Parameter | Canonical SI Value | Semantic Basis | Test Temperature / Context Range | Source Raw Reference | Source Reference | Status |
|---|---|---|---|---|---|---|
| Density | 10.36 g/cm³ | TYPICAL | Test Temp: 20 °C | 10.36 g/cm³ | ASTM International & Standards Technical Committees | VERIFIED |
Sterling Silver 925 Thermal & Thermodynamic Properties
Phase change temperatures, thermal conductivity, specific heat, mean coefficients of thermal expansion across standardized temperature ranges, and recommended thermal processing windows.
| Property Parameter | Canonical SI Value | Semantic Basis | Test Temperature / Context Range | Source Raw Reference | Source Reference | Status |
|---|---|---|---|---|---|---|
| Thermal Conductivity | 410 W/(m·K) | TYPICAL | Test Temp: 20 °C | 410 W/(m·K) | ASTM International & Standards Technical Committees | VERIFIED |
| Melting Range (Solidus-Liquidus) | 779 – 893 °C | RANGE | Solidus 779°C (Ag-Cu eutectic point), Liquidus 893°C | 779 – 893 °C | ASTM International & Standards Technical Committees | VERIFIED |
Sterling Silver 925 Electrical Properties
Electrical conductivity and resistivity in their reported units and conditions.
| Property Parameter | Canonical SI Value | Semantic Basis | Test Temperature / Context Range | Source Raw Reference | Source Reference | Status |
|---|---|---|---|---|---|---|
| Electrical Conductivity | 84 % IACS | TYPICAL | Test Temp: 20 °C | 84 % IACS | ASTM International & Standards Technical Committees | VERIFIED |
| Electrical Resistivity | 20.5 nΩ·m | TYPICAL | Test Temp: 20 °C | 20.5 nΩ·m | ASTM International & Standards Technical Committees | VERIFIED |
Sterling Silver 925 Mechanical Properties
Contextual Mechanical Properties & Tempers: Engineering strength, ductility, and hardness values grouped by product form, temper, and section thickness. Mechanical properties are contextual and not isotropic averages.
| Product Form | Temper / Condition | Section Size | Tensile (UTS) | Yield Strength | Elongation | Shear Strength | Fatigue Strength | Hardness (Scales Preserved) | Status |
|---|---|---|---|---|---|---|---|---|---|
| Strip, Sheet, Wire | Annealed (O Temper)Source values and qualifiersYield Strength (0.2% Offset): ≥ 125 MPa (TYPICAL)ASTM E8 / ISO 6892-1ASTM International & ISO / DIN Standards Technical Committees — ASTM B742, ASTM B413, ISO 9202, DIN 17510 Ultimate Tensile Strength: ≥ 220 MPa (TYPICAL)ASTM E8 / ISO 6892-1ASTM International & ISO / DIN Standards Technical Committees — ASTM B742, ASTM B413, ISO 9202, DIN 17510 | — | ≥ 220 MPa | ≥ 125 MPa | — | — | — | — | VERIFIED |
| Strip, Sheet, Wire | Annealed (O Temper)Source values and qualifiersElongation at Break: ≥ 28 % (TYPICAL)ASTM International & ISO / DIN Standards Technical Committees — ASTM B742, ASTM B413, ISO 9202, DIN 17510 | — · in 50 mm (2 in) | — | — | ≥ 28 % | — | — | — | VERIFIED |
| Strip & Wire | Precipitation Aged (Heat Treated 300°C)Source values and qualifiersYield Strength (0.2% Offset): ≥ 220 MPa (TYPICAL)ASTM International & ISO / DIN Standards Technical Committees — ASTM B742, ASTM B413, ISO 9202, DIN 17510 Ultimate Tensile Strength: ≥ 320 MPa (TYPICAL)ASTM International & ISO / DIN Standards Technical Committees — ASTM B742, ASTM B413, ISO 9202, DIN 17510 Elongation at Break: ≥ 14 % (TYPICAL)ASTM International & ISO / DIN Standards Technical Committees — ASTM B742, ASTM B413, ISO 9202, DIN 17510 | — | ≥ 320 MPa | ≥ 220 MPa | ≥ 14 % | — | — | — | VERIFIED |
| Strip & Wire | Hard Rolled / Hard Drawn (H Temper, 50% reduction)Source values and qualifiersYield Strength (0.2% Offset): ≥ 350 MPa (TYPICAL)ASTM International & ISO / DIN Standards Technical Committees — ASTM B742, ASTM B413, ISO 9202, DIN 17510 Ultimate Tensile Strength: ≥ 430 MPa (TYPICAL)ASTM International & ISO / DIN Standards Technical Committees — ASTM B742, ASTM B413, ISO 9202, DIN 17510 Elongation at Break: ≥ 4 % (TYPICAL)ASTM International & ISO / DIN Standards Technical Committees — ASTM B742, ASTM B413, ISO 9202, DIN 17510 | — | ≥ 430 MPa | ≥ 350 MPa | ≥ 4 % | — | — | — | VERIFIED |
| Standard Product Form | Annealed (O Temper)Source values and qualifiersHV Hardness: 62–78 HV (TYPICAL)ASTM International & ISO / DIN Standards Technical Committees — ASTM B742, ASTM B413, ISO 9202, DIN 17510 | — | — | — | — | — | — | 62–78 HV | VERIFIED |
| Standard Product Form | Precipitation Aged (Heat Treated 300°C)Source values and qualifiersHV Hardness: 110–140 HV (TYPICAL)ASTM International & ISO / DIN Standards Technical Committees — ASTM B742, ASTM B413, ISO 9202, DIN 17510 | — | — | — | — | — | — | 110–140 HV | VERIFIED |
| Standard Product Form | Hard Rolled / Hard Drawn (H Temper, 50% reduction)Source values and qualifiersHV Hardness: 145–175 HV (TYPICAL)ASTM International & ISO / DIN Standards Technical Committees — ASTM B742, ASTM B413, ISO 9202, DIN 17510 | — | — | — | — | — | — | 145–175 HV | VERIFIED |
Sterling Silver 925 Processing & Fabrication
Machining, joining, forming, and thermal processing ratings cataloged from the cited authoritative technical reference.
Machinability
Rated at approximately 45% relative to C36000. Chips shear more cleanly than fine silver; tool life is good when using positive rake carbide inserts and flood oil/emulsion coolant.
Weldability & Joining
Readily brazed using silver solder (AWS BAg-1 to BAg-7). Subject to firescale (subsurface cuprous oxide Cu2O formation) when heated in oxidizing atmospheres without flux.
Heat Treatment & Working Ranges
Precipitation hardenable: Solution heat treat at 740°C to 760°C for 15-30 minutes and rapid water quench; artificial age at 280°C to 300°C for 45-60 minutes to achieve peak hardness of 110-140 HV.
Forming & Cold Working
Excellent cold working characteristics; readily stamped, coined, and rolled with periodic annealing at 600°C.
Sterling Silver 925 Equivalent & Comparable Grades
Comparable Grades & Cross-References: Carefully classified cross-reference relationships for Sterling Silver 925. Comparable does not mean equivalent.
| Related Material | Family | Relationship Classification | Metallurgical Notes & Differences | Status | Action |
|---|---|---|---|---|---|
| Fine Silver 999 | Silver & Silver Alloys | Commonly Compared | Sterling Silver 925 offers more than 2.4× the yield strength of Fine Silver 999 (135 MPa vs 55 MPa) and responds to precipitation heat treatment, at the cost of reduced conductivity (84% vs 106% IACS) and increased susceptibility to firescale.Materials serve different design priorities (e.g. higher strength vs superior corrosion resistance or cost). | VERIFIED | Side-by-Side Compare → |
| C11000 ETP Copper | Copper Alloys | Commonly Compared | Sterling silver provides high electrical conductivity (84% IACS) with superior atmospheric tarnish resistance and higher annealed hardness than pure C11000 copper.Materials serve different design priorities (e.g. higher strength vs superior corrosion resistance or cost). | VERIFIED | Side-by-Side Compare → |
| Silver 900 | Silver & Silver Alloys | Commonly Compared | Adjacent standard alloy; 900 coin silver incorporates 10% Cu yielding higher wear resistance and higher hard-drawn hardness (165 HV vs 160 HV).Materials serve different design priorities (e.g. higher strength vs superior corrosion resistance or cost). | VERIFIED | Side-by-Side Compare → |
Sources
Sources & Provenance Trail: Authoritative reference publications, standards specifications, and data registers cited across this material record.
Authoritative data harmonized across ASTM B742, ASTM B413, ISO 9202, DIN 17510, British Hallmarking Act 1973, and ASM International monographs.