Specifications
Surface Treatments
Certifications
- ISO 9001 - 2015 Certified
- PED 2014/68/EC
- NACE MR0175/ISO 15156-2
- NORSOK M-650
- DFAR
- MERKBLATT AD 2000 W2/W7/W10
René 41 / UNS N07041 Gamma-Prime Nickel-Base Superalloy — Jet Engine Combustor Bolts, Turbine Disks & Aerospace Sheet (AMS 5712 / 5713 / 5719 / 5800)
René 41 (also written Rene 41, R41, R-41, UNS N07041, Werkstoff 2.4973, NiCr19Co11Mo, GE designation B50TF20, Rolls-Royce MSRR 7045) is a cobalt-bearing, gamma-prime-hardenable nickel-base superalloy developed by GE Aircraft Engines in the early 1950s and proven in the B-58 Hustler skin, the X-15 hypersonic research vehicle, the Apollo Command Module heat shield ring frame, and the Saturn V J-2 engine. Nominal composition is 53.5 percent nickel balance, 19 percent chromium, 11 percent cobalt, 9.75 percent molybdenum, 3.1 percent titanium, 1.5 percent aluminium, 0.09 percent carbon and 0.005 percent boron per AMS 5712. The age-hardened condition delivers 1240 MPa (180 ksi) tensile, 760 MPa (110 ksi) yield, 14 percent elongation with stress-rupture life of 100 hours at 690 MPa and 732 degrees Celsius. Service envelope is sustained service to 870 degrees Celsius (1600 degrees Fahrenheit) for combustor liners and turbine disks. René 41 is covered by AMS 5712 (bar, forging stock), AMS 5713 (welding wire), AMS 5719 (sheet, strip, plate), AMS 5800 (forgings), AMS 5545 (sheet alternate), ASTM B637 (precipitation-hardenable nickel-alloy bar), GE B50TF20, Rolls-Royce MSRR 7045 and DIN 17742 Werkstoff 2.4973.
René 41 is supplied by TorqBolt as aerospace fasteners, combustor bolts, stud bolts, nuts, washers, threaded rod, round bar, plate, sheet, tubing, turbine disk forgings, flanges, and welding wire. Mechanical properties on solution-treated and aged bar per AMS 5712: tensile 1240 MPa min (180 ksi), yield 760 MPa min (110 ksi), elongation 14 percent in 4D, hardness 36 to 42 HRC, stress-rupture 100 hours at 690 MPa and 732 degrees Celsius. The gamma-prime Ni3(Al,Ti) precipitate at 22 to 26 volume percent is what carries the load above 700 degrees Celsius where Inconel 718 (gamma-double-prime, derate above 650 degrees Celsius) falls off.
Rene 41 Characteristics and Key Properties
René 41 is engineered for jet engine combustor liners, turbine disks, turbine wheels, combustion chamber casings, afterburner hardware, exhaust nozzles, and bolting at hot-section flanges from 540 to 870 degrees Celsius. The 19 percent chromium and 9.75 percent molybdenum build solid-solution strengthening; the 3.1 percent titanium plus 1.5 percent aluminium drive the gamma-prime Ni3(Al,Ti) coherent precipitate that delivers the high-temperature creep-rupture life. Cobalt at 11 percent stabilises the gamma-prime against coarsening and raises the gamma-prime solvus to 1066 degrees Celsius. Service temperature range is approximately minus 253 to 870 degrees Celsius continuous; cryogenic ductility is retained for liquid-hydrogen turbopump fasteners. Hot-strength rank: at 760 degrees Celsius René 41 carries 690 MPa stress-rupture for 1000 hours where Waspaloy carries 552 MPa, Inconel 718 carries 414 MPa (derated past 650 degrees Celsius), and Inconel 625 carries 240 MPa. The alloy is one of the strongest wrought nickel superalloys ever certified for jet engine hardware.
Rene 41 Trade Names and International Equivalents
René is the General Electric Aircraft Engines designation series for gamma-prime nickel-base superalloys (René 41, René 80, René 95, René 104, René N5). The common name René 41 maps to UNS N07041 chemistry across the following designations. TorqBolt is not authorized by, affiliated with or endorsed by General Electric, Allvac, ATI Specialty Materials or Special Metals.
| Designation | Standard / Body | Notes |
|---|---|---|
| UNS N07041 | Unified Numbering System (USA) | Canonical designation for René 41 |
| AMS 5712 / 5713 / 5719 / 5800 / 5545 | SAE Aerospace Material Specifications | Bar / wire / sheet / forgings / sheet alternate |
| Werkstoff 2.4973 / NiCr19Co11Mo | DIN 17742 (Germany) | European equivalent on legacy procurement |
| GE B50TF20 | General Electric Aircraft Engines | OEM material specification for J47, J79, F101, F110, F404 hot-section parts |
| Rolls-Royce MSRR 7045 | Rolls-Royce Material Specification | UK reference, still cited on Spey, Avon and Conway drawings |
| Pratt & Whitney PWA 1010 | Pratt & Whitney legacy spec | J57, JT3D, J75 hot-section variant call-out |
| ATI 41 / Allvac 41 / Haynes 41 (legacy) | Mill trade names | ATI Specialty Materials, Allvac, Haynes International proprietary heats |
| Waspaloy (UNS N07001) | Sister gamma-prime grade | Lower Ti+Al, easier to forge, slightly lower hot-strength envelope |
| Udimet 700 (UNS N07700) | Sister gamma-prime grade | Higher Mo and Ti, peak strength but harder to forge |
Rene 41 Chemical Composition (UNS N07041 Element Ranges per AMS 5712)
René 41 chemistry per AMS 5712, AMS 5719 (sheet) and ASTM B637. The titanium-plus-aluminium ratio drives the gamma-prime volume fraction; the 9.75 percent molybdenum carries solid-solution strengthening; cobalt at 11 percent raises the gamma-prime solvus. Full element-by-element ranges plus the disambiguation from Waspaloy and Udimet 700 are detailed on the dedicated René 41 chemical composition page.
| Element (wt%) | AMS 5712 Range | Typical Mill Heat | vs Waspaloy (N07001) | vs Udimet 700 (N07700) |
|---|---|---|---|---|
| Nickel | balance | 53.5 | balance (58.0) | balance (53.0) |
| Chromium | 18.0 to 20.0 | 19.0 | 18.0 to 21.0 | 13.0 to 17.0 |
| Cobalt | 10.0 to 12.0 | 11.0 | 12.0 to 15.0 | 17.0 to 20.0 |
| Molybdenum | 9.0 to 10.5 | 9.75 | 3.5 to 5.0 | 4.5 to 5.5 |
| Titanium | 3.0 to 3.3 | 3.1 | 2.75 to 3.25 | 3.0 to 3.5 |
| Aluminium | 1.4 to 1.8 | 1.5 | 1.20 to 1.60 | 3.75 to 4.75 |
| Carbon | 0.06 to 0.12 | 0.09 | 0.02 to 0.10 | 0.07 to 0.15 |
| Boron | 0.003 to 0.010 | 0.005 | 0.003 to 0.010 | 0.020 to 0.040 |
| Iron, max | 5.0 | 0.50 | 2.0 max | 1.0 max |
| Manganese, max | 0.10 | 0.05 | 0.75 max | 0.10 max |
| Silicon, max | 0.50 | 0.20 | 0.75 max | 0.30 max |
| Sulfur, max | 0.015 | 0.005 | 0.015 max | 0.015 max |
| Ti + Al (gamma-prime driver) | 4.4 to 5.1 | 4.6 | 3.95 to 4.85 | 6.75 to 8.25 |
Rene 41 Mechanical Properties (Solution-Treated and Aged, Room and Elevated)
Mechanical requirements per AMS 5712 for solution-treated and aged bar at room temperature; high-temperature stress-rupture per AMS 5712 and Special Metals technical bulletin. Strength is driven by the gamma-prime Ni3(Al,Ti) coherent precipitate at 22 to 26 volume percent; the aging step at 760 degrees Celsius for 16 hours is what delivers the certified envelope.
| Property | AMS 5712 STA RT Minimum | Typical RT Value | At 538°C | At 732°C | At 870°C |
|---|---|---|---|---|---|
| Tensile strength | 1240 MPa (180 ksi) | 1310 to 1380 MPa | 1170 MPa | 1035 MPa | 620 MPa |
| Yield strength (0.2 percent offset) | 760 MPa (110 ksi) | 820 to 900 MPa | 740 MPa | 720 MPa | 500 MPa |
| Elongation in 4D | 14 percent min | 16 to 22 percent | 14 percent | 14 percent | 22 percent |
| Hardness Rockwell C | 36 to 42 HRC | 38 to 40 HRC | n/a | n/a | n/a |
| Stress-rupture (100 h) | n/a | n/a | n/a | 690 MPa (100 ksi) | 240 MPa |
| Stress-rupture (1000 h) | n/a | n/a | n/a | 520 MPa | 165 MPa |
| Density | 8.25 g/cm³ | 8.25 g/cm³ | n/a | n/a | n/a |
| Service temperature range | minus 253 to 870 degrees Celsius continuous | same | same | same | upper service ceiling |
Rene 41 Heat Treatment (Solution 1066°C + Age 760°C / 16h)
The certified René 41 heat-treatment cycle per AMS 5712 is a two-step solution-plus-age process. Step 1: Solution treat at 1066 degrees Celsius (1950 degrees Fahrenheit) for 30 minutes per inch of thickness, then air cool or fan cool to below 540 degrees Celsius within 10 minutes. The 1066 degrees Celsius soak dissolves the gamma-prime back into the gamma matrix and conditions the grain boundaries; the rapid cool is critical to suppress carbide precipitation on the grain boundary that would otherwise embrittle the alloy. Step 2: Age at 760 degrees Celsius (1400 degrees Fahrenheit) for 16 hours, then air cool. The 16-hour age is what nucleates and grows the gamma-prime Ni3(Al,Ti) precipitate to the 22 to 26 volume percent target. Alternative aging at 982 degrees Celsius for 4 hours followed by 760 degrees Celsius for 16 hours (double-age) delivers higher rupture ductility for combustor liner sheet stock. Strain-age cracking is the most common failure mode during welding or stress-relief; the alloy must be solution-treated before welding, then re-solutioned and aged after welding. Forging temperature range 1010 to 1175 degrees Celsius, finish above 1010 degrees Celsius to retain forgeability. Full detail on the dedicated heat treatment page.
Rene 41 Welding (Strain-Age Cracking Risk, ERNiCrCoMo-1 Wire)
René 41 is one of the harder superalloys to weld because of strain-age cracking. The recommended approach is to weld only in the fully solution-treated condition (never on aged stock) and to follow the weld with a re-solution at 1066 degrees Celsius plus re-age at 760 degrees Celsius for 16 hours. Filler per AMS 5713: matching René 41 wire is preferred for matched chemistry; ERNiCrCoMo-1 (Haynes 230 / Inconel 617 wire) is an accepted alternative for combustor-liner GTAW where matched filler is not stocked. Pre-weld preparation must be free of sulfur, lead, zinc, copper and phosphorus contamination; sulfur cracks the weld and zinc embrittles the heat-affected zone. Pre-heat is not required; interpass temperature should stay below 95 degrees Celsius to suppress the gamma-prime nucleation that drives strain-age cracking. The alloy is rarely welded in finished thicknesses above 6 millimetres; thicker hot-section parts are typically machined from solid forging stock. Full procedure detail on the dedicated welding page.
Rene 41 AMS, ASME, AWS, ASTM Specifications
The international specifications relevant to René 41 supply, qualification and inspection. SAE-AMS is the primary procurement language for aerospace hot-section hardware; ASTM B637 covers the precipitation-hardenable nickel-alloy bar family for non-aerospace high-temperature bolting.
| Standard | Scope | Designation |
|---|---|---|
| AMS 5712 | Nickel alloy, corrosion and heat resistant, bars and forgings (René 41 solution treated and aged) | UNS N07041 |
| AMS 5713 | Nickel alloy welding wire, gas tungsten arc and gas metal arc (René 41 matched filler) | UNS N07041 |
| AMS 5719 | Nickel alloy, corrosion and heat resistant, sheet, strip and plate (René 41) | UNS N07041 |
| AMS 5800 | Nickel alloy, corrosion and heat resistant, forgings (René 41 large turbine disk forgings) | UNS N07041 |
| AMS 5545 | Nickel alloy, corrosion and heat resistant, sheet alternate (René 41) | UNS N07041 |
| ASTM B637 | Precipitation-hardenable nickel-alloy bars, forgings and forging stock for high-temperature service | UNS N07041 (listed) / N07718 / N07750 / N07090 |
| GE B50TF20 | General Electric Aircraft Engines material specification | UNS N07041; J47, J79, F101, F110, F404 hot-section call-out |
| Rolls-Royce MSRR 7045 | Rolls-Royce material specification | UNS N07041; Avon, Spey, Conway drawings |
| Pratt & Whitney PWA 1010 | Pratt & Whitney material specification (legacy) | UNS N07041; J57, JT3D, J75 variant call-out |
| DIN 17742 / Werkstoff 2.4973 / NiCr19Co11Mo | German specification for cobalt-bearing gamma-prime nickel-base alloy | 2.4973 / NiCr19Co11Mo |
| AWS A5.14 Class ERNiCrCoMo-1 | Alternative welding wire when matched René 41 filler is not stocked | Haynes 230 / Inconel 617 wire |
Rene 41 vs Inconel 718 vs Waspaloy vs Udimet 700 vs Inconel 625 vs Hastelloy X
René 41 sits in the cobalt-bearing gamma-prime corner of the high-temperature alloy decision matrix. Its closest cousins are Inconel 718 (gamma-double-prime, easier to weld, derate past 650 degrees Celsius), Waspaloy (sister gamma-prime, lower Ti+Al, easier to forge), Udimet 700 (peak strength but harder to forge), Inconel 625 (solid-solution, no aging step, lower hot-strength) and Hastelloy X (combustor sheet workhorse below 1000 degrees Celsius).
| Alloy | UNS | Strengthening | Tensile (RT) | Max Service Temp | vs René 41 |
|---|---|---|---|---|---|
| René 41 | N07041 | Gamma-prime + 9.75 Mo solid-solution | 1240 MPa min | 870°C continuous | Baseline; combustor bolts, turbine disks, exhaust hardware |
| Inconel 718 | N07718 | Gamma-double-prime Ni3Nb | 1240 MPa min | 650°C continuous | Easier to weld; derate above 650°C; use 718 for cooler-section disks |
| Waspaloy | N07001 | Gamma-prime + 4 Mo solid-solution | 1240 MPa min | 815°C continuous | Easier to forge; lower hot-strength; use Waspaloy for large turbine disks |
| Udimet 700 | N07700 | Gamma-prime + Mo + W solid-solution | 1380 MPa typical | 870°C continuous | Peak strength; harder to forge; use Udimet 700 for highest-stress turbine wheels |
| Inconel 625 | N06625 | Solid-solution Mo + Nb (no aging) | 827 MPa min | 982°C continuous (low load) | Lower hot-strength; use 625 for combustion liner skin, not for load-carrying disks |
| Hastelloy X | N06002 | Solid-solution Mo + W + Co | 690 MPa min | 1204°C continuous (low load) | Better oxidation; lower load capacity; use Hastelloy X for combustor sheet |
Rene 41 Applications by Industry (Jet Engine Combustor, Turbine Disk, Aerospace Hardware)
René 41 dominates buyer specifications in seven service environments: jet engine combustor liners, jet engine turbine disks and wheels, combustion chamber casings, afterburner hardware, aerospace fasteners on hot-section flanges, gas turbine industrial bolting, and historical NASA hardware (Apollo Command Module ring frames, Saturn V J-2 turbopump hardware, X-15 leading-edge structure). The alloy is over-specified for cooler-section hardware below 540 degrees Celsius (use Inconel 718 instead) and under-specified for unloaded combustor skin above 1000 degrees Celsius (use Hastelloy X or René 80 instead).
- Jet Engine Combustor Liners: combustion chamber inner and outer liner segments at 760 to 870 degrees Celsius gas-side metal temperature; cooled with compressor bleed air on the cold side.
- Jet Engine Turbine Disks and Wheels: high-pressure turbine disk rim and bore in J47, J79, F101, F110, F404 and CFM56 derivatives; bore temperature 540 to 650 degrees Celsius, rim temperature up to 760 degrees Celsius.
- Combustion Chamber Casings: pressure-containing outer casing surrounding the combustor liner; service 540 to 700 degrees Celsius.
- Afterburner Hardware: flame holders, spray bars and liner segments in the augmentor section of military fighters (F101, F110, F404, F119).
- Aerospace Fasteners: bolts, studs and nuts at hot-section flanges; combustor case fasteners, turbine case bolting, exhaust nozzle attachment hardware; AMS 5712 bar machined to NAS, MS or MIL-S configurations.
- Gas Turbine Industrial Bolting: hot-section bolting on industrial gas turbines (Frame 6, Frame 7, Frame 9 derivatives) where Inconel 718 is derated by service temperature.
- NASA and Aerospace Heritage Hardware: Apollo Command Module heat-shield ring frames, Saturn V J-2 engine turbopump hardware, X-15 hypersonic research vehicle leading-edge structure, B-58 Hustler skin, SR-71 Blackbird hot-structure components.
Rene 41 Forms and Fasteners
TorqBolt holds René 41 stock at the Mumbai warehouse across the bar, sheet and fastener range. India domestic delivery in 3 to 7 working days; export shipments through Mumbai port (JNPT) with full mill test certificate per AMS 5712 / EN 10204 type 3.1 or 3.2, packing list and project-specific documentation. All bar is supplied in the solution-treated condition; fastener-grade heat-treatment to STA is performed in-house under AMS 2759 controls.
| Form Category | Products |
|---|---|
| Bar and rod | Round bar (AMS 5712), welding wire (AMS 5713), threaded rod |
| Sheet, plate, strip | Sheet, plate, strip (AMS 5719 / AMS 5545) |
| Forgings, flanges | Turbine disk forgings (AMS 5800), flanges (AMS 5712 stock) |
| Aerospace fasteners (custom-machined from AMS 5712 bar, heat-treated to STA) | Combustor bolts, hex bolts, heavy hex bolts, stud bolts, socket cap screws, nuts, hex nuts, heavy hex nuts, lock nuts, washers, screws, threaded rod |
Rene 41 Frequently Asked Questions
What is René 41 made of?
René 41 is a cobalt-bearing nickel-base gamma-prime superalloy with nominal composition 53.5 percent nickel balance, 19 percent chromium, 11 percent cobalt, 9.75 percent molybdenum, 3.1 percent titanium, 1.5 percent aluminium, 0.09 percent carbon, 0.005 percent boron, iron 5 max, manganese 0.10 max, silicon 0.50 max and sulfur 0.015 max per AMS 5712. UNS designation is N07041; Werkstoff is 2.4973; DIN designation is NiCr19Co11Mo; GE designation is B50TF20.
What is the difference between René 41 and Inconel 718?
Both alloys carry similar room-temperature tensile strength near 1240 MPa, but the strengthening mechanism is different. René 41 is strengthened by the gamma-prime Ni3(Al,Ti) precipitate at 22 to 26 volume percent; Inconel 718 is strengthened by the gamma-double-prime Ni3Nb precipitate. The gamma-double-prime in Inconel 718 starts to coarsen and lose strength above 650 degrees Celsius; the gamma-prime in René 41 holds load to 870 degrees Celsius. Inconel 718 is much easier to weld (lower strain-age cracking risk); René 41 must be welded in the solution-treated condition and re-solutioned and aged after welding. Choose René 41 for combustor and hot-section hardware above 650 degrees Celsius; choose Inconel 718 for cooler-section turbine disks and structural hardware below 650 degrees Celsius.
What is the difference between René 41 and Waspaloy?
Both are cobalt-bearing gamma-prime nickel superalloys with similar room-temperature tensile near 1240 MPa. René 41 carries higher molybdenum (9.75 percent vs 4.25 percent) for solid-solution strengthening and higher hot-strength to 870 degrees Celsius; Waspaloy carries lower Ti+Al (3.95 to 4.85 percent vs 4.4 to 5.1 percent), which makes it easier to forge and less prone to strain-age cracking during welding. Large turbine disk forgings typically use Waspaloy; smaller combustor bolting, sheet stock and afterburner hardware typically use René 41.
Which AMS specifications cover René 41?
AMS 5712 covers bar and forging stock (the procurement workhorse); AMS 5713 covers matched welding wire; AMS 5719 and AMS 5545 cover sheet, strip and plate; AMS 5800 covers large turbine disk forgings. ASTM B637 lists UNS N07041 in the precipitation-hardenable nickel-alloy bar family for non-aerospace high-temperature service. OEM specifications are GE B50TF20, Rolls-Royce MSRR 7045 and Pratt & Whitney PWA 1010 (legacy).
What is the gamma-prime aging heat-treatment for René 41?
Solution treat at 1066 degrees Celsius (1950 degrees Fahrenheit) for 30 minutes per inch of thickness, then air cool to below 540 degrees Celsius within 10 minutes. Age at 760 degrees Celsius (1400 degrees Fahrenheit) for 16 hours, then air cool. The 16-hour age nucleates and grows the gamma-prime Ni3(Al,Ti) precipitate to the 22 to 26 volume percent target that delivers the certified envelope. A double-age option (982 degrees Celsius for 4 hours followed by 760 degrees Celsius for 16 hours) is used on sheet stock for higher rupture ductility.
What MTC do you supply with René 41?
EN 10204 type 3.1 by default and type 3.2 on request. Heat number, melt-shop pour date (VIM-VAR double-melt or VIM-ESR triple-melt), chemistry per AMS 5712 (including verified Ti, Al, Ti+Al, carbon, boron and trace sulfur, lead, bismuth, silver), mechanical results to AMS 5712 minima in the STA condition, dimensional report tied to the heat lot, hardness reading per ASTM E18, ultrasonic and macroetch inspection per AMS 2154 / AMS 2375, and chemistry traceability to the parent ingot. PMI on request; third-party witness inspection (Lloyds Register, DNV, BV, SGS, TÜV, Bureau of Aircraft Standards) on call-out.
What is gamma-prime in René 41?
Gamma-prime is the coherent precipitate Ni3(Al,Ti) that nucleates inside the gamma matrix during aging at 760 degrees Celsius. The precipitate has an L1-sub-2 ordered FCC crystal structure and is coherent with the gamma matrix (lattice mismatch under 0.5 percent), which is what carries the high-temperature load. In René 41 the gamma-prime volume fraction reaches 22 to 26 percent at the AMS 5712 STA condition, driven by the 3.1 percent titanium plus 1.5 percent aluminium chemistry. Cobalt at 11 percent raises the gamma-prime solvus to 1066 degrees Celsius and stabilises the precipitate against coarsening over the service life.
In which forms is René 41 supplied?
TorqBolt manufactures René 41 in aerospace fasteners, combustor bolts, stud bolts, round bar, welding wire, sheet, plate, turbine disk forgings and flanges.
Satisfaction Survey
