Precious Metal B617-H04
Supply condition
GB B617
H04 = full hard
Most common contact-strip temper — balances wear resistance and stamping formability for bifurcated blades and rivets.
Values for the H04 condition
Other B617 tempers and conditions
B617 is listed in 6 conditions; see the grade overview at B617.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ODefault Annealed | Choose for maximum ductility — rivet heading, deep drawing, cold clinching and brazed contact assemblies. | 65 | 265 | 40 | 58 HB | 85 % IACS |
Quarter hard | Light stiffening for flat strip that must stay dead-flat during stamping yet still be formed tightly. | 175 | 300 | 28 | 72 HB | 85 % IACS |
Half hard | General stamping temper: better blanked-edge quality and rivet shank strength with useful remaining ductility. | 240 | 345 | 20 | 86 HB | 84 % IACS |
H04This page Full hard | Most common contact-strip temper — balances wear resistance and stamping formability for bifurcated blades and rivets. | 310 | 400 | 10 | 100 HB | 84 % IACS |
Extra hard | Use where contact-force retention and abrasion resistance matter more than tight bending. | 385 | 450 | 6 | 112 HB | 83 % IACS |
Spring hard | Maximum as-rolled hardness for sliding/wiping contacts and thin flat springs with only gentle forming. | 450 | 500 | 3 | 124 HB | 83 % IACS |
What is B617-H04?
B617-H04 is B617 supplied in the H04 condition — most common contact-strip temper — balances wear resistance and stamping formability for bifurcated blades and rivets. B617-H04 has a yield strength of 310 MPa (45 ksi) and a tensile strength of 400 MPa (58 ksi) — stronger than 93% of precious metal grades. Elongation at break is 10% and the elastic modulus is 79 GPa (11.5 Msi). B617-H04 has a density of 10.31 g/cm³ (0.372 lb/in³), lighter than 52% of precious metal grades. It melts at 779°C (1,434 °F). O is the default condition FabDigit quotes; H04 is available on request or by drawing note.
Advantages
- Easy to machine — 63/100, better than 100% of precious metal grades
- High strength — 310 MPa (45 ksi), better than 93% of precious metal grades
- Conducts heat well — 354 W/m·K (204.5 BTU/hr·ft·°F), better than 91% of precious metal grades
- High electrical conductivity — 84 % IACS, better than 87% of precious metal grades
- Polishes to a fine finish — 95/100, better than 86% of precious metal grades
Limitations
- Limited service temperature — 150°C (302 °F), worse than 100% of precious metal grades
- Limited ductility — 10%, worse than 89% of precious metal grades
- Limited formability — 58/100, worse than 87% of precious metal grades
- Low stiffness — 79 GPa (11.5 Msi), worse than 86% of precious metal grades
B617-H04 properties
Typical room-temperature values for B617-H04; 14 are specific to this condition. Other listed values are B617 reference data and may not represent this condition. Bars are the position among precious metal grades.
Physical3
B617-H04 has a density of 10.31 g/cm³ (0.372 lb/in³), lighter than 52% of precious metal grades. It melts at 779°C (1,434 °F).
Mechanical12
B617-H04 has a yield strength of 310 MPa (45 ksi) and a tensile strength of 400 MPa (58 ksi) — stronger than 93% of precious metal grades. Elongation at break is 10% and the elastic modulus is 79 GPa (11.5 Msi).
Thermal6
B617-H04 is rated for continuous service to 150°C (302 °F). It conducts heat at 354 W/m·K (204.5 BTU/hr·ft·°F), better than 91% of precious metal grades. Thermal expansion is 18.7 µm/m·K (10.4 µin/in·°F).
Electrical3
B617-H04 conducts electricity at 84 % IACS, better than 87% of precious metal grades.
Chemical & Environmental3
Corrosion resistance is very good (78/100), worse than 56% of precious metal grades.
Sustainability4
Producing a kilogram of B617-H04 takes about 1,500 MJ of energy and emits 100 kg of CO₂ — more than 51% of precious metal grades. Typical recycled content is 45%.
Manufacturability8
B617-H04's machinability is good (63/100, better than 100% of precious metal grades); weldability good (55/100); formability good (58/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with B617-H04
Is B617 easy to machine?
Machines cleanly with sharp, high-rake carbide or HSS tools and light oil; soft tempers are gummy and burr — prefer 1/2-hard or harder for turned rivets and collect all chips for refining.
Can B617 be welded?
Joined mainly by resistance/projection welding, laser welding or brazing to Cu/brass carriers; fusion welding is uncommon and requires protection against copper oxidation and gas pickup.
Can B617 be formed, bent or molded?
Annealed strip and wire stamp, head, coin and deep-draw excellently; interanneal at 600–650 °C after ~50 % reduction and quench or cool in a reducing atmosphere to avoid firescale.
What surface finishes work on B617?
Buffs to a mirror; bright-dip or citric/thiourea pickle removes copper firescale; anti-tarnish protection is by Rh, Au or thin Sn/Ni plating or a lacquer — anodizing does not apply.
B617 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 |
|---|---|---|
| Agsilver content per ASTM B617 | 89.5 – 90.5 | 90 |
| Other (total impurities)Pb, Fe, Bi, Sb etc. kept low for workability | ≤ 0.15 | — |
| Cubalance copper | ≥ 9.5 (balance) | — |
B617-H04 — frequently asked
What is B617-H04 used for?
B617-H04 is typically used for low-voltage switch contacts, relay contact rivets and connector contact tips. In short: standardised contact rivet stock; wear-resistant fine-silver substitute; very high formability rating.
What is the yield strength of B617-H04?
B617-H04 has a typical yield strength of 310 MPa (45 ksi) and a tensile strength of 400 MPa (58 ksi) — stronger than 93% of precious metal grades. Strength varies by condition: see the 6 listed tempers.
Is B617-H04 easy to machine?
Reasonably — machinability is rated good (63/100, better than 100% of precious metal grades). Machines cleanly with sharp, high-rake carbide or HSS tools and light oil; soft tempers are gummy and burr — prefer 1/2-hard or harder for turned rivets and collect all chips for refining.
Can B617-H04 be welded?
Yes — weldability is rated good (55/100). Joined mainly by resistance/projection welding, laser welding or brazing to Cu/brass carriers; fusion welding is uncommon and requires protection against copper oxidation and gas pickup.
What surface finishes work on B617-H04?
Buffs to a mirror; bright-dip or citric/thiourea pickle removes copper firescale; anti-tarnish protection is by Rh, Au or thin Sn/Ni plating or a lacquer — anodizing does not apply.
Can B617-H04 be formed, bent or molded?
Annealed strip and wire stamp, head, coin and deep-draw excellently; interanneal at 600–650 °C after ~50 % reduction and quench or cool in a reducing atmosphere to avoid firescale.
What is the maximum service temperature of B617-H04?
B617-H04 is rated for continuous use to about 150°C (302 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between B617-O and B617-H08?
O is the default condition — choose for maximum ductility — rivet heading, deep drawing, cold clinching and brazed contact assemblies. H08: maximum as-rolled hardness for sliding/wiping contacts and thin flat springs with only gentle forming. Yield strength is 65 MPa in O versus 450 MPa in H08.
Sources
- ASTM B617 — Standard Specification for Coin Silver Electrical Contact Alloy — ASTM International (2019)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials (Precious Metals & Electrical Contact Materials) — ASM International (1990)
- ASM Specialty Handbook: Electrical Contact Materials chapter — ASM International (1998)
- Silver-copper contact strip and rivet alloy data (Ag90Cu10) — Deringer-Ney / Metalor / AMI Doduco (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.