Equivalent Grades & Cross-Reference
Cross-reference designations across UNS, EN/DIN, ISO, SAE, and JIS standards. Comparable does not mean directly interchangeable. Always verify composition tolerance limits and mechanical requirements.
International standard designations are established by distinct standards bodies with differing testing standards (e.g. ASTM E8 vs ISO 6892-1). Even when chemical compositions overlap, allowable trace impurities (such as phosphorus, sulfur, or iron), grain size requirements, temper nomenclature, and minimum elongation criteria can differ.
Never authorize a structural alloy substitution without verifying the governing procurement specification, temper, ruling section size, and environmental compatibility.
Relationship Classification Governance
Show All TypesIdentical chemical composition and mechanical requirements across different naming authorities.
Rule: Direct 1:1 dual specification permissible subject to certified mill test reports (MTR).Officially recognized counterpart in another national or international engineering standard (e.g. ASTM to EN).
Rule: Chemical limits or testing protocols may have subtle differences (e.g. tighter P/S ceilings or impact requirements). Engineering review required before substitution.Substantially identical chemistry and overlapping mechanical envelope, but slight variations in allowable trace elements or testing protocols exist across governing standards.
Rule: Direct commercial substitution is generally permissible subject to certified Mill Test Report (MTR) confirmation for critical applications.Similar base alloy chemistry and general functional properties, but noticeable divergence in allowable impurity ceilings, cold-work response, or minimum yield requirements.
Rule: Engineering substitution review required. Design calculations must verify temper, formability, and corrosion limits before specifying as a direct replacement.Similar base chemistry and functional performance envelope, but not officially harmonized by standards organizations.
Rule: Comparable does not mean equivalent. Heat treatment response and dimensional tolerances may diverge.Close metallurgical alternative when the primary grade is unavailable or obsolete.
Rule: Design parameters (weldability, hardenability, fatigue limit) must be re-evaluated for the specific application.Frequently evaluated side-by-side during trade-off studies or alloy selection.
Rule: Materials serve different design priorities (e.g. higher strength vs superior corrosion resistance or cost).Materials superficially mistaken for equivalents that exhibit critical metallurgical incompatibilities.
Rule: DO NOT SUBSTITUTE without full engineering re-qualification.| Source Alloy (UNS) | Relationship Type | Target Grade / Standard | Engineering Scope & Nuance | Actions |
|---|---|---|---|---|
| Fine Silver 999Fine Silver | Commonly Compared | Sterling Silver 925Confidence: HIGH | Fine Silver 999 provides peak electrical and thermal conductivity (106% IACS vs 84% IACS) and immunity to firescale oxidation, but Sterling Silver 925 provides substantially higher mechanical hardness (70 HV vs 28 HV annealed) and yield strength. | |
| Fine Silver 999Fine Silver | Commonly Compared | C11000 ETP CopperConfidence: HIGH | Fine Silver is the only elemental engineering metal possessing higher electrical conductivity (106% IACS) and thermal conductivity (429 W/(m·K)) than standard C11000 ETP Copper (100% to 101% IACS, 388 W/(m·K)). | |
| Fine Silver 999Fine Silver | Commonly Compared | Britannia Silver 958Confidence: HIGH | Britannia 958 incorporates 4.16% copper to increase yield strength to ~90 MPa while retaining closer conductivity and ductility to pure silver than sterling 925. | |
| Britannia Silver 958Alloyed Silver | Commonly Compared | Sterling Silver 925Confidence: HIGH | Britannia 958 is softer and more ductile in the annealed condition (55 HV vs 70 HV, elongation 38% vs 32%), facilitating deep spinning with fewer intermediate anneals than sterling. | |
| Britannia Silver 958Alloyed Silver | Commonly Compared | Fine Silver 999Confidence: HIGH | Britannia 958 offers 63% higher yield strength (90 MPa vs 55 MPa) while retaining 92% IACS conductivity. | |
| Silver 950Alloyed Silver | Commonly Compared | Sterling Silver 925Confidence: HIGH | Silver 950 has higher silver content (95.0% vs 92.5%) and slightly higher ductility, but slightly lower peak age-hardening potential than sterling silver. | |
| Silver 950Alloyed Silver | Commonly Compared | Britannia Silver 958Confidence: HIGH | Silver 950 is marginally harder and stronger than Britannia 958 (105 MPa vs 90 MPa yield strength) due to 5% Cu vs 4.16% Cu. |