Precious Metal B628-H04 vs B628-O
Precious Metal · B628 temper comparison
B628-H04 and B628-O are two conditions of the same precious metal grade, B628: H04 (full hard) versus O (annealed). The chemistry is identical, so every difference below comes from the condition. B628-H04 is the stronger of the two: yield strength 420 MPa (60.9 ksi) against 130 MPa (18.9 ksi) for B628-O, about 3.2 times as much; tensile strength follows at 460 MPa (66.7 ksi) vs 280 MPa (40.6 ksi). In exchange, B628-O is the more ductile: elongation 25% versus 6% for B628-H04, and B628-H04 is harder (114 HB vs 62 HB). B628-O runs hotter in service (300°C vs 150°C continuous). On the shop floor, B628-H04 machines more easily (68 vs 55 out of 100).
B628-H04Choose it when strength drives the design, or when the part is machined in volume.
B628-OChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
B628-H04 vs B628-O: 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.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Shear Strength
Fatigue Strength (Endurance Limit)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 92 GPa13.3 Msi · Shear Modulus 34 GPa4.9 Msi · Bulk Modulus 110 GPa16 Msi · Poisson's Ratio 0.36 · Reduction in Area 55% · Compressive Strength 280 MPa40.6 ksi
Physical
Density and transition temperatures.
Same in both: Density 10 g/cm³0.36 lb/in³ · Melting Point (Solidus) 779°C1,434 °F · Liquidus Temperature 779°C1,434 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Max Service Temperature (continuous)
Same in both: Specific Heat Capacity 250 J/kg·K0.06 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 18.5 µm/m·K10.3 µin/in·°F · Latent Heat of Fusion 130 J/g55.9 BTU/lb · Min Service Temperature -200°C-328 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) 0.05 V · Corrosion Resistance 72 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Formability (cold)
Same in both: Machinability Rating (AISI 1212 = 100 %) 60% · Weldability 55 / 100 · Castability 80 / 100 · Brazeability / Solderability 98 / 100 · Polishability 90 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 1,100 MJ/kg472,915 BTU/lb · Embodied Carbon (primary production) 105 kg CO₂/kg · Embodied Water 260 L/kg31.2 gal/lb · Typical Recycled Content 60%
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.
B628-H04 vs B628-O — frequently asked
Is B628-H04 stronger than B628-O?
Yes. B628-H04 has a typical yield strength of 420 MPa (60.9 ksi) against 130 MPa (18.9 ksi) for B628-O — about 3.2 times as much. Tensile strength is 460 MPa (66.7 ksi) vs 280 MPa (40.6 ksi).
Which condition does FabDigit quote by default, H04 or O?
O is the default B628 condition in the FabDigit quote flow. The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.
Which is easier to machine, B628-H04 or B628-O?
B628-H04, by a small margin. Both rate good for machinability — 68/100 against 55/100 for B628-O.
Ready to make it?
Upload a CAD file and FabDigit prices the part in B628-H04 and B628-O 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.