Precious Metal Pt950
Pt950 is a 95 wt % platinum alloy with the balance usually Ru, Ir, Co or Cu as solid-solution strengtheners (Pt950Ru, Pt950Ir, Pt950Co).
Reference datasheet — Pt950 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the O condition
Pt950 tempers and conditions
Pt950 is supplied in 4 conditions, soft to hard. O is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ODefault Annealed | Pick the annealed, recrystallized temper as standard stock for sheet, strip, wire and tube: 35 % elongation suits stamping, drawing, stone setting and further cold forming, at the lowest strength. | 130 | 310 | 35 | 105 HB | — |
investment / centrifugal cast, no post heat treatment | Use as-cast investment or centrifugal castings for complex small jewellery parts; coarse grain and some shrinkage porosity hold tensile strength to 350 MPa, below wrought material. | 175 | 350 | 22 | 124 HB | 7 % IACS |
low-temperature stress relief after cold work or welding | Use a low-temperature stress relief after cold work or welding to remove internal stress while keeping part of the cold-work strength, preventing cracked settings or dimensional drift. | 250 | 400 | 20 | 142 HB | 7 % IACS |
hard temper (approx. 40–60 % reduction) | Choose the hard temper from roughly 40–60 % cold reduction for spring wire, prongs, electrode wire and fine tubing needing 560 MPa yield and wear resistance; elongation falls to 3 %. | 560 | 650 | 3 | 235 HB | — |
What is Pt950?
Pt950 is a 95 wt % platinum alloy with the balance usually Ru, Ir, Co or Cu as solid-solution strengtheners (Pt950Ru, Pt950Ir, Pt950Co). It is the mainstream international jewelry platinum and is also used for crucibles, electrodes, thermocouple sheaths, medical implants and catalytic parts, offering near-perfect corrosion and oxidation resistance, service to 1200 °C, 35 % elongation and good laser weldability. Limits are very high density (about 20 g/cm³), high raw-material cost, poor machinability from tool sticking, and low annealed strength (130 MPa yield, 310 MPa tensile, 105 HB) that must be raised by cold work or alloy selection. Pt950 has a density of 20.1 g/cm³ (0.726 lb/in³), heavier than 94% of precious metal grades. It melts at 1,755°C (3,191 °F). Pt950 has a yield strength of 130 MPa (18.9 ksi) and a tensile strength of 310 MPa (45 ksi) — weaker than 72% of precious metal grades. Elongation at break is 35% and the elastic modulus is 172 GPa (24.9 Msi).
What is Pt950 used for?
- Bridal jewelry and wedding bands
- Watch cases and bezels
- Laboratory crucibles and dishes
- Electrodes
- Thermocouple sheaths
- Medical implant components
- Catalytic components
Advantages
- Good corrosion resistance — 100/100, better than 98% of precious metal grades
- High service temperature — 1,200°C (2,192 °F), better than 97% of precious metal grades
- Readily welded — 85/100, better than 93% of precious metal grades
- Stiff — 172 GPa (24.9 Msi), better than 90% of precious metal grades
- Polishes to a fine finish — 95/100, better than 86% of precious metal grades
Limitations
- High embodied carbon — 16,000 kg CO₂/kg, worse than 96% of precious metal grades
- Heavy — 20.1 g/cm³ (0.726 lb/in³), worse than 94% of precious metal grades
- Low electrical conductivity — 7.2 % IACS, worse than 87% of precious metal grades
- Difficult to machine — 30/100, worse than 86% of precious metal grades
- Poor heat conductor — 40 W/m·K (23.1 BTU/hr·ft·°F), worse than 85% of precious metal grades
Pt950 properties
Typical room-temperature values for Pt950-O; bars are the position among precious metal grades.
Physical3
Pt950 has a density of 20.1 g/cm³ (0.726 lb/in³), heavier than 94% of precious metal grades. It melts at 1,755°C (3,191 °F).
Mechanical11
Pt950 has a yield strength of 130 MPa (18.9 ksi) and a tensile strength of 310 MPa (45 ksi) — weaker than 72% of precious metal grades. Elongation at break is 35% and the elastic modulus is 172 GPa (24.9 Msi).
Thermal6
Pt950 is rated for continuous service to 1,200°C (2,192 °F). It conducts heat at 40 W/m·K (23.1 BTU/hr·ft·°F), worse than 85% of precious metal grades. Thermal expansion is 9 µm/m·K (5 µin/in·°F).
Electrical3
Pt950 conducts electricity at 7.2 % IACS, worse than 87% of precious metal grades.
Chemical & Environmental3
Corrosion resistance is excellent (100/100), better than 98% of precious metal grades.
Sustainability4
Producing a kilogram of Pt950 takes about 250,000 MJ of energy and emits 16,000 kg of CO₂ — more than 95% of precious metal grades. Typical recycled content is 35%.
Manufacturability8
Pt950's machinability is poor (30/100, worse than 86% of precious metal grades); weldability excellent (85/100); formability excellent (90/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the precious metal family
Yield strength against density for every precious metal grade FabDigit runs. Pt950 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Pt950
Is Pt950 easy to machine?
Highly prone to sticking and built-up edge: use sharp positive-rake carbide or diamond tools at high speed and low feed with generous lubrication. Recover all chips and grinding dust for refining.
Can Pt950 be welded?
Laser spot welding, pulsed TIG and oxy-hydrogen torch welding all perform well and can be run autogenously without flux. Avoid Pb, Bi, S and Si contamination and contact with silicon-bearing refractories, which cause high-temperature embrittlement.
Can Pt950 be formed, bent or molded?
Cold formability in the annealed temper is excellent, above 90 % deformation, with interstage anneals at 900–1000 °C. Casting requires vacuum or centrifugal equipment, zirconia or yttria shells and a pouring temperature of about 1850–1900 °C.
Pt950 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 |
|---|---|---|
| RuPt950Ru: most common wrought/cast jewellery variant | 0 – 5 | 5 |
| IrPt950Ir (Pt-Ir 950): best ductility; wire, electrodes, medical | 0 – 5 | |
| CoPt950Co: best casting flow, high as-cast hardness, weakly magnetic | 0 – 5 | |
| CuPt950Cu: lower cost, medium hardness, common in EU/Asia jewellery | 0 – 5 | |
| PdPt950Pd: soft, easily worked; used for prongs and solder joints | 0 – 5 | |
| WPt950W: high-hardness wrought variant | 0 – 5 | |
| other (total)Fe, Si, Pb, Bi limited; Pb/Bi cause high-temp embrittlement | 0 – 0.15 | |
| PtPt950 / 950 hallmark requires at least 95.0 wt% platinum | ≥ 95 (balance) |
What surface finishes work on Pt950?
Takes a mirror polish directly and needs no plating; sandblasting, brushing and laser engraving are all practical. Use dust extraction during polishing to recover precious metal fines.
How much does Pt950 cost?
Pt950 is a specialty-cost precious metal ($$$$$), pricier than about 100% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Pt950 — frequently asked
What is Pt950 used for?
Pt950 is typically used for bridal jewelry and wedding bands, watch cases and bezels, laboratory crucibles and dishes, electrodes, thermocouple sheaths and medical implant components. In short: premium platinum jewelry alloy.
What is the yield strength of Pt950?
Pt950 has a typical yield strength of 130 MPa (18.9 ksi) and a tensile strength of 310 MPa (45 ksi) — weaker than 72% of precious metal grades. Strength varies by condition: see the 4 listed tempers.
Is Pt950 easy to machine?
Not especially — machinability is rated poor (30/100, worse than 86% of precious metal grades). Highly prone to sticking and built-up edge: use sharp positive-rake carbide or diamond tools at high speed and low feed with generous lubrication. Recover all chips and grinding dust for refining.
Can Pt950 be welded?
Yes — weldability is rated excellent (85/100). Laser spot welding, pulsed TIG and oxy-hydrogen torch welding all perform well and can be run autogenously without flux. Avoid Pb, Bi, S and Si contamination and contact with silicon-bearing refractories, which cause high-temperature embrittlement.
What surface finishes work on Pt950?
Takes a mirror polish directly and needs no plating; sandblasting, brushing and laser engraving are all practical. Use dust extraction during polishing to recover precious metal fines.
Can Pt950 be formed, bent or molded?
Cold formability in the annealed temper is excellent, above 90 % deformation, with interstage anneals at 900–1000 °C. Casting requires vacuum or centrifugal equipment, zirconia or yttria shells and a pouring temperature of about 1850–1900 °C.
What is the maximum service temperature of Pt950?
Pt950 is rated for continuous use to about 1,200°C (2,192 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does Pt950 cost?
Pt950 is a specialty-cost precious metal ($$$$$), pricier than about 100% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASM Handbook Vol.2: Properties and Selection — Nonferrous Alloys (Precious Metals) — ASM International (1990)
- ASM Handbook Vol.13B: Corrosion — Materials (Platinum Group Metals) — ASM International (2005)
- Platinum jewellery alloy data (Pt950Ru / Pt950Ir / Pt950Co) — Johnson Matthey / PGM refiners (2021)
- ASTM B684 / B561 — Platinum and platinum alloy products — ASTM (2019)
- Precious metal LCA / embodied energy datasets — Granta / ecoinvent (2022)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.