HAYNES® R-41 alloy

Principle Features
Vacuum-melted, nickel-based HAYNES® R-41 (UNS N07041) alloy has exceptionally
high strength at temperatures in the range of 1200 to 1800°F (649 to 982°C). The alloy
is a precipitation-hardening type and strength is developed by various solution annealing
and aging heat treatments. Because of its high strength and good oxidation resistance,
the alloy is being used in afterburner parts and nozzle diaphragm partitions in current gas
turbine engines. In the annealed condition, the alloy is ductile and has essentially the same
forming characteristics as 18-8 stainless steel and other nickel-based alloys. It is stronger,
however, and has a greater resistance to forming. The alloy has been formed with success
on drop hammers, expanding mandrels and stretch formers. R-41 alloy is now being
replaced in many applications by HAYNES® 282® alloy, due to the superior fabricability of
282® alloy.

Mechanical properties can be tailored by selecting various combinations of solution

annealing and aging treatments. In general, higher solution heat treating temperatures
result in better room-temperature ductility and improved formability. Stress-rupture strength
is also improved by this type of treatment. Lower solution annealing temperatures produce
higher tensile strengths at temperatures up to about 1700°F (927°C). The effect of solution
heat treating temperature can be seen in tensile and stress-rupture data.

Nominal Composition
Weight %
Nickel: 52 Balance
Chromium: 19
Cobalt: 11
Iron: 5 max.
Molybdenum: 10
Titanium: 3.1
Aluminum: 1.5
Silicon: 0.5 max.
Manganese: 0.1 max.
Carbon: 0.09
Boron: 0.006
Zirconium: 0.07 max.

H-3056C © 2019 Haynes International

Physical Properties
Physical Property Bristish Units Metric Units
Density 70°F 0.298 lb/in3 21°C 8.25 g/cm3
Melting Temperature 2250-2535°F - 1232-1391°C -
70-1000°F 7.5 µin/in -°F 21-538°C 13.5 x 10-6m/m·°C
70-1200°F 7.8 µin/in -°F 21-649°C 14.0 x 10-6m/m·°C
70-1400°F 8.2 µin/in -°F 25-760°C 14.8 x 10-6m/m·°C
Mean Coefficient of
70-1500°F 8.5 µin/in -°F 25-816°C 15.2 x 10-6m/m·°C
Thermal Expansion
70-1600°F 8.8 µin/in -°F 25-871°C 15.7 x 10-6m/m·°C
70-1700°F 9.1 µin/in -°F 25-927°C 16.3 x 10-6m/m·°C
70-1800°F 9.4 µin/in -°F 25-982°C 16.8 x 10-6m/m·°C
300°F 80 Btu-in/ft2-hr-°F 149°C 11.5 W/m-°C
400°F 87 Btu-in/ft2-hr-°F 204°C 12.5 W/m-°C
500°F 95 Btu-in/ft2-hr-°F 260°C 13.6 W/m-°C
600°F 102 Btu-in/ft2-hr-°F 316°C 14.7 W/m-°C
800°F 117 Btu-in/ft2-hr-°F 427°C 16.8 W/m-°C
Thermal 1000°F 131 Btu-in/ft2-hr-°F 538°C 18.8 W/m-°C
Conductivity 1100°F 139 Btu-in/ft2-hr-°F 593°C 20.0 W/m-°C
1200°F 146 Btu-in/ft2-hr-°F 649°C 21.0 W/m-°C
1300°F 153 Btu-in/ft2-hr-°F 704°C 22.0 W/m-°C
1400°F 161 Btu-in/ft2-hr-°F 760°C 23.1 W/m-°C
1500°F 168 Btu-in/ft2-hr-°F 816°C 24.1 W/m-°C
1600°F 175 Btu-in/ft2-hr-°F 871°C 25.1 W/m-°C
Specific Heat 70°F 0.108 Btu/lb.-°F 21°C 452 J/kg-°C
Electrical Resistivity 32°F 50.0 µohm-in 0°C 127.0 µohm-cm
Magnetic Permeability 70°F <1.002 at 200 oersteds 21°C <1.002 at 200 oersteds

Haynes International - HAYNES® R-41 alloy

Tensile Data
Tensile properties after heat treating at
2050°F (1121°C) /30 min./RAC + 1650°F (899°C) /4h/AC
Test 0.2% Ultimate Tensile 4D
Temperature Yield Strength Strength Elongation
°F °C ksi MPa ksi MPa %
RT RT 116.4 803 181.8 1253 20.5
400 204 109* 752* 174.2* 1201* 16.5*
800 427 109.1* 752* 161.6* 1114* 20.3*
1000 538 107.2 739 161 1110 21.2
1200 649 107.7 743 172.9 1192 19.3
1400 760 114.3 788 139.1 959 28.3
1500 816 104* 717* 115.7* 798* 27.2*
1600 871 79.7 550 89.2 615 28.5
1700 927 59.1* 407* 66.9* 461* 24.8*
1800 982 34.2 236 40.2 277 31.1
2000 1093 4.9* 34* 8.5* 59* 94.4*
*Limited data

Tensile properties after heat treating at 1400°F (760°C) /16h/AC

Test 0.2% Ultimate Tensile 4D
Temperature Yield Strength Strength Elongation
°F °C ksi MPa ksi MPa %
RT RT 154.3 1064 205.4 1416 22.3
400 204 141.2* 974* 198.2* 1367* 23.0*
800 427 141.8* 978* 181.6* 1252* 25.6*
1000 538 139.8 964 182.6 1259 20.5
1200 649 138.3 954 196.2 1353 23.4
1400 760 126.1 869 150.8 1040 17.9
1500 816 112.2 774 128.1 883 19.4
1600 871 83.9 578 98.5 679 31.4
1700 927 51.1 352 62.3 430 38.7
1800 982 25.9 179 34.5 238 42.7
*Limited data

Haynes International - HAYNES® R-41 alloy

Oxidation Resistance
Static Oxidation Testing
Environment: Flowing Air
Test Duration: 1,008 h
Number of Cycles: 6
Cycle Length: 168 h
Temperatures: 1600, 1700, 1800°F (871, 927, 982°C)
Metal Loss = (A-B)/2
Average Internal Penetration = C
Maximum Internal Penetration = D
Average Metal Affected = Metal Loss + Average Internal Penetration
Maximum Metal Affected = Metal Loss + Maximum Internal Penetration

Comparative Oxidation Resistance in Flowing Air, 1008 Hours

1600°F (871°C) 1700°F (927°C) 1800°F (982°C)
Metal Loss, Avg. Met. Aff. Metal Loss, Avg. Met. Aff. Metal Loss, Avg. Met. Aff.
mils (µm) mils, (µm) mils (µm) mils, (µm) mils (µm) mils, (µm)
Alloy mils μm mils μm mils μm mils μm mils μm mils μm
263 0.1 3 0.4 10 0.2 5 0.7 18 0.9 23 5.0 127
282® 0.2 5 0.6 15 0.1 3 1.1 28 0.2 5 1.8 46
R-41 0.2 5 0.8 20 0.2 5 1.5 38 0.2 5 2.9 74
Waspaloy 0.3 8 1.4 36 0.3 8 3.4 86 0.7 18 5.0 127

Dynamic Oxidation Testing (Burner Rig)

Burner rig oxidation tests were conducted by exposing, in a rotating holder, samples 0.375
inch x 2.5 inches x thickness (9.5mm x 64mm x thickness) to the products of combustion of
fuel oil (2 parts No. 1 and 1 part No. 2), burned at an air to fuel ratio of about 50:1. The gas
velocity was about 0.3 mach. Samples were automatically removed from the gas stream
every 30 minutes and fan cooled to less than 500°F (260°C) and then reinserted into the
flame tunnel.
1600°F (871°C), 1000 hours, 30 minute cycles 1800°F (982°C), 1000 hours, 30 minute cycles
Metal Loss, Avg. Met. Aff. Metal Loss, Avg. Met. Aff.
mils (µm) mils, (µm) mils (µm) mils, (µm)
Alloy mils μm mils μm mils μm mils μm
263 1.4 36 4.0 102 12.5 318 16.1 409
282® 1.8 46 4.2 107 8.0 203 13.0 330
Waspaloy 1.9 48 4.3 109 9.5 241 13.6 345
R-41 1.2 30 4.4 112 5.8 147 12.1 307

Haynes Internaitonal - HAYNES® R-41 alloy

Aged Hardness
Age Hardened Room Temperature Hardness
Form Hardness Heat Treatment
Sheet 35 HRC 2050F, 30 Min, AC + 1650F, 4 Hr, AC
Plate 36 HRC 2050F, 30 Min, AC + 1650F, 4 Hr, AC
Sheet 42 HRC 1400F, 16 Hr, AC
Plate 39 HRC 1400F, 16 Hr, AC
HRC = Hardness Rockwell “C”

Creep-Rupture
HAYNES® R-41 Sheet, Age-Hardened*
Approximate Initial Stress to Produce Specified Creep in
Temperature Creep 100h 1,000h
°F °C % ksi MPa ksi MPa
1 105 724 84 579
1200 649
R 110 758 90 621
1 75 517 59 407
1300 704
R 85 586 68 469
1 53 365 34 234
1400 760
R 63 434 43 296
1 32 221 18 124
1500 816
R 39 269 24 165
1 17 117 9.0 62
1600 871
R 23 159 13 90
1 8.4 58 4.6 32
1700 927
R 13 90 6.5 45
*Samples were age hardened by heat treating at 2050°F (1121°C) /30 min./RAC +
1650°F (899°C) /4h/AC

Haynes International - HAYNES® R-41 alloy

Thermal Stability
Baseline Tensile Properties at RT and ET; Residual Tensile Properties at
Room Temperature and Exposure Temperature
Condition Test 0.2% Ultimate Tensile 4D
Temperature Yield Strength Strength Elongation
°F °C ksi MPa ksi MPa %
Solution Annealed RT RT 83.6 576 151.4 1044 38.7
RT RT 116.8 805 178.6 1231 17.3
1200 649 103.1 711 169.6 1169 18.0
Age Hardened* 1400 760 111.6 769 138.2 953 28.4
1500 816 100.6 694 113.5 783 32.0
1600 871 78.1 538 87.9 606 30.0
Age Hardened* + RT RT 150.7 1039 188.5 1300 5.3
1200°F/8000h 1200 649 129.7** 894** 182.6 1259 8.1**
Age Hardened* + RT RT 151.6** 1045** 173.9** 1199** 0.1
1400°F/8000h 1400 760 88.2 608 126.8 874 30.1**
Age Hardened* + RT RT 113.5 783 156.6 1080 1.4
1500°F/8000h 1500 816 58.2 401 88.5 610 26.8
Age Hardened* + RT RT 83.3 574 122.9 847 2.0
1600°F/8000h 1600 871 36.3 250 60.9 420 33.0
*Aged hardened at 2050°F (1121°C)/30 MAT/AC + 1650°F (899°C)/4H/AC
**Limited data

Elastic Modulus
Elastic Modulus, Share Modulus, and Poisson’s Ratio
Test Temperature Modulus of Elasticity Shear Modulus Poisson's
°F °C 106 psi GPa 10 psi
6
GPa Ratio
80 27 31.6 218 12 83 0.31
300 149 30.9 213 12 81 0.31
500 260 29.6 204 11 77 0.32
700 371 28.7 198 11 75 0.32
900 482 27.6 190 10 72 0.32
1000 538 27.2 188 - - -
1100 593 26.4 182 10 69 0.33
1200 649 25.9 179 - - -
1250 677 25.8 178 10 67 0.33
1400 760 24.8 171 9 64 0.33
1500 816 24.1 166 - - -
1550 843 23.7 163 9 61 0.34
1600 871 23.2 160 - - -
1700 927 21.8 150 8 55 0.35

Haynes International - HAYNES® R-41 alloy

Heat Treatment
Wrought HAYNES® R-41 alloy is furnished in the solution annealed condition unless oth-
erwise specified. After component fabrication, the alloy would normally again be solution
annealed at 1950°F - 2150°F (1066°C - 1177°C) for a time commensurate with section
thickness and rapidly cooled or water-quenched for optimal properties. Following solution
annealing, the alloy is given an age-hardening treatment to optimize the microstructure and
induce age-hardening. A variety of age hardening practices are used commercially, all of
which include heat treating in the range of 1400°F - 1800°F (760°C - 982°C). For example,
AMS 5545 specifies age hardening samples at 1400°F (760°C) for a minimum of 16 hours
and air cooling.

Fabrication
Solution Annealed Room Temperature Hardness
Form Hardness Typical ASTM Grain Size
Sheet 98 HRBW 5 - 7.5
Plate 31 HRC 4-6
HRBW = Hardness Rockwell “B”, Tungsten Indentor.
HRC = Hardness Rockwell “C”.
R-41, Solution Annealed, Room Temperature Tensile
Test 0.2% Ultimate Tensile 4D
Temperature Yield Strength Strength Elongation
Form °F °C ksi MPa ksi MPa %
Sheet RT RT 84.2 581 148.1 1021 44.7
Plate RT RT 101.0 696 195.0 1344 38.8
For welding HAYNES® R-41 alloy, please review the General Welding and Joining
Guidelines. In addition to those guidelines, there are some additional considerations when
welding R-41 alloy.

HAYNES® R-41 alloy is a precipitation-strengthened alloy and requires a postweld heat

treatment (PWHT) to develop suitable properties. Postweld heat treatment for R-41 alloy
consists of two parts: a solution anneal, which is followed by a suitable aging treatment.
Details can be found in the Heat Treatment section. During PWHT, the gamma-prime
phase (Ni3Al,Ti) precipitates and the alloy undergoes a slight volumetric contraction. This
makes it susceptible to strain-age cracking, which typically occurs upon heating to the
solution annealing temperature. To inhibit strain-age cracking, the heating rate to the
solution annealing temperature should be as fast as possible, within the capability of the
furnace being used.

Filler metal of matching composition is suggested for welding R-41 alloy to itself. For
filler metal suggestions for welding R-41 alloy to other alloys, please refer to the Haynes
Welding SmartGuide, or contact Haynes International for further guidance.

Haynes International - HAYNES® R-41 alloy

Low Cycle Fatigue
Comparative Low-Cycle Fatigue Data

Haynes Internaitonal - HAYNES® R-41 alloy

Specifications and Codes
Specifications
HAYNES® R-41 alloy
(N07041)
Sheet, Plate & Strip AMS 5545
Billet, Rod & Bar AMS 5712
Coated Electrodes -
Bare Welding Rods & Wire AMS 5800
Seamless Pipe & Tube -
Welded Pipe & Tube -
Fittings -
Forgings AMS 5712
DIN -
Others -

Codes
HAYNES® R-41
(N07041)
MMPDS 6.3.7

Disclaimer:
Haynes International makes all reasonable efforts to ensure the accuracy and correctness of the data in this docu-
ment but makes no representations or warranties as to the data’s accuracy, correctness or reliability. All data are for
general information only and not for providing design advice. Alloy properties disclosed here are based on work con-
ducted principally by Haynes International, Inc. and occasionally supplemented by information from the open literature
and, as such, are indicative only of the results of such tests and should not be considered guaranteed maximums or
minimums. It is the responsibility of the user to test specific alloys under actual service conditions to determine their
suitability for a particular purpose.

For specific concentrations of elements present in a particular product and a discussion of the potential health affects
thereof, refer to the Safety Data Sheets supplied by Haynes International, Inc. All trademarks are owned by Haynes
International, Inc., unless otherwise indicated.

Haynes International - HAYNES® R-41 alloy