Refractory Metal Pure Re-SR (Stress relieved)
Heat-treated state
also Re CP
Compromise condition: retains most cold-work strength while removing residual stress for dimensional stability.
Values for the SR condition
Other Pure Re tempers and conditions
Pure Re is listed in 4 conditions; see the grade overview at Pure Re.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Vacuum AnnealedDefault fully recrystallized (1600–1800 °C, high vacuum) | Standard stocked condition for sheet, rod and thermocouple stock where maximum ductility and formability are needed. | 300 | 1,100 | 24 | 22 HRC | 8.9 % IACS |
powder-pressed and vacuum/H₂ sintered blank | Lowest-cost near-net blank for crucibles and electrodes; slightly porous, so strength and conductivity are below wrought values. | 500 | 900 | 8 | 30 HRC | 8 % IACS |
SRThis page Stress relieved | Compromise condition: retains most cold-work strength while removing residual stress for dimensional stability. | 1,200 | 1,550 | 10 | 49 HRC | 8.6 % IACS |
Cold worked | Pick for maximum room-temperature strength, spring elements and thin foil where no further forming is required. | 1,900 | 2,100 | 3 | 63 HRC | 8.3 % IACS |
What is Pure Re-SR?
Pure Re-SR is Pure Re heat treated to SR — compromise condition: retains most cold-work strength while removing residual stress for dimensional stability. Pure Re-SR has a yield strength of 1,200 MPa (174 ksi) and a tensile strength of 1,550 MPa (225 ksi) — stronger than 96% of refractory metal grades. Elongation at break is 10% and the elastic modulus is 463 GPa (67.2 Msi). Pure Re-SR has a density of 21.02 g/cm³ (0.759 lb/in³), heavier than 99% of refractory metal grades. It melts at 3,186°C (5,767 °F). Vacuum Annealed is the default condition FabDigit quotes; SR is available on request or by drawing note.
Advantages
- Stiff — 463 GPa (67.2 Msi), better than 99% of refractory metal grades
- High strength — 1,200 MPa (174 ksi), better than 96% of refractory metal grades
- High service temperature — 1,400°C (2,552 °F), better than 81% of refractory metal grades
Limitations
- High embodied carbon — 700 kg CO₂/kg, worse than 100% of refractory metal grades
- Heavy — 21.02 g/cm³ (0.759 lb/in³), worse than 99% of refractory metal grades
- Difficult to machine — 9/100, worse than 89% of refractory metal grades
Pure Re-SR properties
Typical room-temperature values for Pure Re-SR; 22 are specific to this condition. Other listed values are Pure Re reference data and may not represent this condition. Bars are the position among refractory metal grades.
Physical3
Pure Re-SR has a density of 21.02 g/cm³ (0.759 lb/in³), heavier than 99% of refractory metal grades. It melts at 3,186°C (5,767 °F).
Mechanical17
Pure Re-SR has a yield strength of 1,200 MPa (174 ksi) and a tensile strength of 1,550 MPa (225 ksi) — stronger than 96% of refractory metal grades. Elongation at break is 10% and the elastic modulus is 463 GPa (67.2 Msi).
Thermal6
Pure Re-SR is rated for continuous service to 1,400°C (2,552 °F). It conducts heat at 47 W/m·K (27.2 BTU/hr·ft·°F), better than 60% of refractory metal grades. Thermal expansion is 6.2 µm/m·K (3.44 µin/in·°F).
Electrical3
Pure Re-SR conducts electricity at 8.6 % IACS, better than 58% of refractory metal grades.
Chemical & Environmental2
Corrosion resistance is very good (70/100), worse than 61% of refractory metal grades.
Sustainability3
Producing a kilogram of Pure Re-SR takes about 11,000 MJ of energy and emits 700 kg of CO₂ — more than 100% of refractory metal grades. Typical recycled content is 30%.
Manufacturability7
Pure Re-SR's machinability is not recommended (9/100, worse than 89% of refractory metal grades); weldability poor (25/100); formability poor (25/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Pure Re-SR
Is Pure Re easy to machine?
Very difficult: gummy, work-hardens instantly and galls — use ground carbide/CBN at low speed with heavy positive rake, or prefer grinding, wire EDM and electrochemical machining.
Can Pure Re be welded?
Join by electron-beam or laser welding in high vacuum, or by vacuum brazing with Pd-, Ni- or Au-base fillers; any C/O/N pickup embrittles the weld, and resistance/TIG welding in air is not acceptable.
Can Pure Re be formed, bent or molded?
Cold roll, draw or spin in many light passes (10–20 % per pass) with intermediate 1600–1800 °C vacuum anneals; never hot work in air, and avoid contact with carbon tooling or lubricants that leave residue.
What surface finishes work on Pure Re?
Chemically or electrolytically clean, then mechanically polish or electropolish; parts for oxidizing service must be coated (Ir, HfC or Pt) since bare Re volatilizes above ~600 °C in air.
Pure Re 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.
| Element | Spec limit (wt %) |
|---|---|
| Moprincipal metallic impurity from APR route | ≤ 0 |
| W | ≤ 0 |
| Fe | ≤ 0 |
| Ni | ≤ 0 |
| Ca | ≤ 0 |
| Kresidual from ammonium perrhenate reduction | ≤ 0 |
| C | ≤ 0.01 |
| Ointerstitial; must be low to avoid grain-boundary embrittlement | ≤ 0.01 |
| N | ≤ 0 |
| H | ≤ 5×10⁻⁴ |
| Remetals-basis purity, typical CP grade 99.99 % (3N5–4N also sold) | ≥ 99.99 (balance) |
Pure Re-SR — frequently asked
What is Pure Re-SR used for?
Pure Re-SR is typically used for rocket combustor liners with iridium coating, W-Re high-temperature thermocouples, filaments and ion source components, mass spectrometer ribbons, electrical contacts and heating elements and X-ray tube targets. In short: ultra-high-temp rhenium foil.
What is the yield strength of Pure Re-SR?
Pure Re-SR has a typical yield strength of 1,200 MPa (174 ksi) and a tensile strength of 1,550 MPa (225 ksi) — stronger than 96% of refractory metal grades. Strength varies by condition: see the 4 listed tempers.
Is Pure Re-SR easy to machine?
Not especially — machinability is rated not recommended (9/100, worse than 89% of refractory metal grades). Very difficult: gummy, work-hardens instantly and galls — use ground carbide/CBN at low speed with heavy positive rake, or prefer grinding, wire EDM and electrochemical machining.
Can Pure Re-SR be welded?
Not readily — weldability is rated poor (25/100). Join by electron-beam or laser welding in high vacuum, or by vacuum brazing with Pd-, Ni- or Au-base fillers; any C/O/N pickup embrittles the weld, and resistance/TIG welding in air is not acceptable.
What surface finishes work on Pure Re-SR?
Chemically or electrolytically clean, then mechanically polish or electropolish; parts for oxidizing service must be coated (Ir, HfC or Pt) since bare Re volatilizes above ~600 °C in air.
Can Pure Re-SR be formed, bent or molded?
Cold roll, draw or spin in many light passes (10–20 % per pass) with intermediate 1600–1800 °C vacuum anneals; never hot work in air, and avoid contact with carbon tooling or lubricants that leave residue.
What is the maximum service temperature of Pure Re-SR?
Pure Re-SR is rated for continuous use to about 1,400°C (2,552 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Pure Re Vacuum Annealed and Pure Re-CW?
Vacuum Annealed is the default condition — standard stocked condition for sheet, rod and thermocouple stock where maximum ductility and formability are needed. CW: pick for maximum room-temperature strength, spring elements and thin foil where no further forming is required. Yield strength is 300 MPa in Vacuum Annealed versus 1,900 MPa in CW.
Sources
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials (Refractory Metals) — ASM International (1990)
- CRC Handbook of Chemistry and Physics, 102nd ed. — CRC Press (2021)
- Rhenium metal — sheet, rod, wire and CVD product data — Rhenium Alloys, Inc. (2023)
- Rhenium powder and pellets technical data — H.C. Starck Solutions (2022)
- ASTM B885 — Standard Specification for Rhenium Powder / GB/T 26016 — ASTM / SAC (2016)
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.