Precious Metal AuCo5 vs Silver 999
Precious Metal · grade comparison
Precious Metal AuCo5 and Silver 999 are both precious metal grades. AuCo5 is the stronger of the two: yield strength 650 MPa (94.3 ksi) against 55 MPa (7.98 ksi) for Silver 999, about 12 times as much; tensile strength follows at 750 MPa (109 ksi) vs 140 MPa (20.3 ksi). In exchange, Silver 999 is the more ductile: elongation 48% versus 3% for AuCo5, and AuCo5 is harder (200 HV vs 27 HV). Silver 999 is lighter (10.49 g/cm³ vs 18.2 g/cm³ for AuCo5) and AuCo5 is stiffer (95 GPa vs 76 GPa). On the shop floor, AuCo5 welds better (very good vs good) and AuCo5 sits in a lower cost tier (high, $$$$) than Silver 999 (specialty, $$$$$).
AuCo5Choose it when strength drives the design, or when it will be welded.
Silver 999Choose it when the part is bent, formed or impact-loaded, or when weight is the constraint.
AuCo5 vs Silver 999: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all precious metal grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all precious metal grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Shear Modulus
Bulk Modulus
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Shear Strength
Fatigue Strength (Endurance Limit)
Hardness, Vickers
Reduction in Area
Hardness, Brinell
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Liquidus Temperature
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Max Service Temperature (continuous)
Min Service Temperature
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Galvanic Potential (seawater, vs SCE)
Corrosion Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Castability
Brazeability / Solderability
Polishability
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Typical Recycled Content
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
Strength versus weight
Yield strength against density for every precious metal grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | AuCo5 | Silver 999 |
|---|---|---|
| Default condition | — | O |
| Relative cost | $$$$ High | $$$$$ Specialty |
| Min. machined wall | — | — |
| Best machined surface | — | — |
AuCo5 vs Silver 999 — frequently asked
Is AuCo5 stronger than Silver 999?
Yes. AuCo5 has a typical yield strength of 650 MPa (94.3 ksi) against 55 MPa (7.98 ksi) for Silver 999 — about 12 times as much. Tensile strength is 750 MPa (109 ksi) vs 140 MPa (20.3 ksi).
Which is cheaper, AuCo5 or Silver 999?
AuCo5 is the lower-cost material: it sits in the high tier ($$$$) while Silver 999 is specialty ($$$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.
Which is easier to machine, AuCo5 or Silver 999?
AuCo5, by a small margin. Both rate fair for machinability — 45/100 against 40/100 for Silver 999; for welding the order is AuCo5 first (very good, 70/100) then Silver 999 (good, 60/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in AuCo5 and Silver 999 side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.
Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.