Principal Features

Excellent High-temperature Strength and Good Oxidation Resistance

HAYNES® 25 alloy (UNS R30605) is a cobalt-nickel-chromium-tungsten alloy that combines excellent high-temperature strength with good resistance to oxidizing environments up to 1800°F (980°C) for prolonged exposures, and excellent resistance to sulfidation. It can be fabricated and formed by conventional techniques, and has been used for cast components. Other attractive features include excellent resistance to metal galling.

Applications

HAYNES® 25 alloy combines properties which make it suitable for a number of component applications in the aerospace industry, including parts in established military and commercial gas turbine engines. In modern engines, it has largely been replaced by newer materials such as HAYNES® 188 alloy, and, most recently, 230® alloy, which possess improved properties. Another area of significant usage for HAYNES® 25 alloy is as a bearing material, for both balls and races.

*Please contact our technical support team if you have technical questions about this alloy.

Nominal Composition

Weight %
Cobalt 51 Balance
Nickel 10
Iron 3 max.
Chromium 20
Molybdenum 1 max.
Tungsten 15
Manganese 1.5
Silicon 0.4 max.
Carbon 0.1

Creep and Stress-Rupture Strength

HAYNES® 25 alloy is a solid-solution-strengthened material which possesses excellent high-temperature strength. It is particularly effective for very long-term applications at temperatures of 1200 to 1800°F (650 to 980°C). It is stronger than nickel-base solid-solution-strengthened alloys, and is the strongest of the cobalt-base materials which still have good fabrication characteristics.

Solution-Annealed Sheet*

Temperature Creep Approximate Initial Stress to Produce Specified Creep in
10 h 100 h 1,000 h
°F °C % ksi MPa ksi MPa ksi MPa
1200 649 0.5 62.0 427 47.5 328 33.5** 231**
1 71.0 490 54.0 372 39.0** 269**
R 82.0 565 69.0 476 57.0 393
1300 704 0.5 43.0 296 30.0** 207** 21.0** 145**
1 49.5 341 35.0 241 23.2** 160**
R 64.0 441 50.0 345 38.0 262
1400 760 0.5 28.0 193 19.5 134 14.8** 102**
1 32.0 221 21.5 148 16.2** 112**
R 47.0** 324** 36.0 248 26.0 179
1500 816 0.5 18.5 128 14.0 97 10.2** 70**
1 20.2 139 15.5 107 12.3** 85**
R 34.0** 234** 24.7 170 18.1 125
1600 871 0.5 13.7 94 9.9 68 6.9** 48**
1 15.2 105 12.0 83 8.9** 61**
R 24.0** 165** 17.5 121 12.0 83
1700 927 0.5 9.7 67 6.8 47 4.5** 31**
1 12.0 83 8.8 61 5.6 39
R 17.3** 119** 11.8 81 7.2 50
1800 982 0.5 6.8 47 4.5 31 2.6 18
1 8.8 61 5.6 39 3.0 21
R 11.8** 81** 7.2 50 4.0 28
200 1093 0.5 2.8 19 1.3 9.0
1 3.3 23 1.4 9.7
R 4.5 31 2.0 14

*Based on limited data
**Significant extrapolation

Solution-Annealed Bar

Temperature Approximate Initial Stress to Produce Rupture in
10 h 100 h 1,000 h
°F °C ksi MPa ksi MPa ksi MPa
1350 732 42.5 293 36.5 252 30.3 209
1400 760 39.2 270 31.5 217 24.1 166
1500 816 30.0 207 22.0 152 17.0 117
1600 871 23.0 159 16.5 114 12.0 83
1700 927 17.0 117 12.0 83 8.4 58
1800 982 11.5 79 7.5 52 5.0 34

Comparative Rupture Strength, Sheet

Tensile Properties

Solution-Annealed Plate

Test Temperature 0.2% Offset Yield Strength Ultimate Tensile Strength Elongation
°F °C ksi MPa ksi MPa %
RT 68.7 474 145.1 1000 58.8
1000 538 38.4 265 122.1 842 71.0
1200 649 33.4 230 123.5 852 64.3
1400 760 34.4 237 86.0 593 45.7
1600 871 32.0 221 48.3 333 104.7
1800 982 18.7 129 27.3 188 113.7
2000 1093 9.3 64 14.5 100 97.5

Solution-Annealed Sheet

Test Temperature 0.2% Offset Yield Strength Ultimate Tensile Strength Elongation
°F °C ksi MPa ksi MPa %
RT 69.0 476 144.5 996 54.7
1000 538 38.8 268 119.0 820 63.4
1200 649 37.2 256 119.3 823 54.2
1400 760 35.5 245 82.5 569 33.9
1600 871 33.5 231 46.3 319 97.8
1800 982 18.6 128 25.8 178 94.1
2000 1093 9.0 62 13.3 92 63.0

Hot-Rolled and 2250°F (1230°C) Solution-Annealed Bar*

Test Temperature 0.2% Offset Yield Strength Ultimate Tensile Strength Elongation
°F °C ksi MPa ksi MPa %
RT 73 505 147 1015 60
1000 538 43 295 113 780 63
1200 649 43 295 105 725 49
1400 760 41 285 90 620 29
1600 871 34 235 54 370 29
1800 982 19 130 28 195 41

*Limited data
RT = Room Temperature

*Elevated temperature tensile tests for bar were performed with a strain rate that is no longer standard. These results were from tests with a strain rate of 0.005 in./in./minute through yield and a crosshead speed of 0.5 in./minute for every inch of reduced test section from yield through failure. The current standard is to use a strain rate of 0.005 in./in./minute though yield and a crosshead speed of 0.05 in./minute for every inch of reduced test section from yield through failure.

Hardness and Grain Size

Form Hardness, HRBW Typical ASTM Grain Size
Sheet 97 3.5 – 5.5
Plate 99 3.5 – 5
Bar 98 3.5 – 5

All samples tested in solution-annealed condition
HRBW = Hardness Rockwell “B”, Tungsten Indentor.

Cold-Worked Properties

HAYNES® 25 alloy has excellent strength and hardness characteristics in the cold-worked condition. These high property levels are also evident at elevated temperature, making 25 alloy quite suitable for applications such as ball bearings and bearing races. A modest additional increase in hardness and strength can be achieved through aging of the cold-worked material.

Typical Tensile Properties, Cold-Worked Sheet*

Cold Reduction Test Temperature 0.2% Offset Yield Strength Ultimate Tensile Strength Elongation
% °F °C ksi MPa ksi MPa %
10 70 20 105 725 155 1070 41
100 540 78 540 114 785 48
1200 650 80 550 115 795 37
1400 760 67 460 87 600 8
1600 870 47 325 62 425 13
1800 980 27 185 39 270 15
15 70 20 124 855 166 1145 30
1000 540 107 740 134 925 29
1200 650 111 765 129 890 15
1400 760 86 595 104 715 5
1600 870 52 360 70 485 9
1800 980 30 205 40 275 5
20 70 20 141 970 183 1260 19
1000 540 133 915 156 1075 18
1200 650 120 825 137 945 2
1400 760 96 660 107 740 3
1800 980 30 205 41 285 4

*Limited data for cold-rolled 0.050-inch (1.3 mm) thick sheet

Typical Tensile Properties, Cold-Worked and Aged Sheet*

Condition Test Temperature 0.2% Offset Yield Strength Ultimate Tensile Strength Elongation
% °F °C ksi MPa ksi MPa %
15% CW + Age A 70 20 136 940 168 1160 31
1200 650 104 715 128 885 23
20% CW + Age A 70 20 152 1050 181 1250 17
1000 540 129 890 151 1040 19
1200 650 128 885 144 995 8
1400 760 97 670 108 745 2
1600 870 59 405 74 510 6
1800 980 33 230 43 295 5
20% CW + Age B 70 20 162 1115 191 1315 16
600 315 132 910 165 1140 28
1000 540 124 855 149 1025 23
1200 650 119 820 140 965 13
1400 760 92 635 116 800 7
1600 870 50 345 71 490 9
1800 980 31 215 42 290 12

*Limited data for cold-rolled 0.050-inch (1.3 mm) thick sheet
Age A = 700°F (370°C)/1 hour
Age B = 1100°F (595°C)/2 hours

Typical Hardness at 70°F (20°C), Cold-Worked and Aged Sheet*

Cold-work HRC, After Indicated Level of Cold Work and Subsequent Aging Treatment
900°F (480°C) 1100°F (595°C)
% None 5 h 5 h
None 24 25 25
5 31 33 31
10 37 39 39
15 40 44 43
20 44 44 47

*Limited data for cold-rolled 0.070-inch (1.8 mm) thick sheet
HRC = Hardness Rockwell “C”.

Impact Strength

Impact Strength Properties, Plate

Test Temperature Typical Charpy V-Notch Impact Resistance
°F °C ft.-lbs. J
-321 -196 109 148
-216 -138 134 182
-108 -78 156 212
-20 -29 179 243
RT RT 193 262
500 260 219 297
1000 540 201 273
1200 650 170 230
1400 760 143 194
1600 870 120 163
1800 980 106 144

Thermal Stability

When exposed for prolonged periods at intermediate temperatures, HAYNES® 25 alloy exhibits a loss of room temperature ductility in much the same fashion as some other solid-solution-strengthened superalloys, such as HASTELLOY® X alloy or alloy 625. This behavior occurs as a consequence of the precipitation of deleterious phases. In the case of a 25 alloy, the phase in question is CO2W laves phase. HAYNES® 188 alloy is significantly better in this regard than 25 alloy; however, for applications where thermal stability is important, 230® alloy is an even better selection.

Room-Temperature Properties of Sheet After Thermal Exposure*

Exposure Temperature 0.2% Offset Yield Strength Ultimate Tensile Strength Elongation
°F °C h ksi MPa ksi MPa %
None 0 66.8 460 135.0 930 48.7
1200 650 500 70.3 485 123.6 850 39.2
1000 92.3 635 140.0 965 24.8
2500 95.1 655 130.7 900 12.0
1400 760 100 68.9 475 115.3 795 18.1
1600 870 100 72.1 495 113.6 785 9.1
500 77.3 535 126.1 870 3.5
1000 81.7 565 142.0 980 5.0

*Composite of multiple sheet lot tests

Physical Properties

Physical Property British Units Metric Units
Density RT
0.327 lb/in3
RT
9.07 g/cm3
Melting Range 2425-2570°F 1330-1410°C
Electrical Resistivity RT 34.9 µohm-in RT 88.6 µohm-cm
200°F 35.9 µohm-in 100°C 91.8 µohm-cm
400°F 37.6 µohm-in 200°C 95.6 µohm-cm
600°F 38.5 µohm-in 300°C 97.6 µohm-cm
800°F 39.1 µohm-in 400°C 98.5 µohm-cm
1000°F 40.4 µohm-in 500°C 100.8 µohm-cm
1200°F 41.8 µohm-in 600°C 104.3 µohm-cm
1400°F 42.3 µohm-in 700°C 106.6 µohm-cm
1600°F 40.6 µohm-in 800°C 107.8 µohm-cm
1800°F 37.7 µohm-in 900°C 101.1 µohm-cm
1000°C 95.0 µohm-cm
Thermal Diffusivity 70°F
4.4 x 10-3in2/sec
RT
28.3 x 10-3cm2/sec
125°F
4.6 x 10-3in2/sec
100°C
30.1 x 10-3cm2/sec
200°F
4.8 x 10-3in2/sec
200°C
32.7 x 10-3cm2/sec
400°F
5.5 x 10-3in2/sec
300°C
35.6 x 10-3cm2/sec
600°F
6.0 x 10-3in2/sec
400°C
41.2 x 10-3cm2/sec
800°F
6.5 x 10-3in2/sec
500°C
43.5 x 10-3cm2/sec
1000°F
6.9 x 10-3in2/sec
600°C
45.5 x 10-3cm2/sec
1200°F
7.3 x 10-3in2/sec
700°C
47.6 x 10-3cm2/sec
1400°F
7.6 x 10-3in2/sec
800°C
49.6 x 10-3cm2/sec
1600°F
7.7 x 10-3in2/sec
900°C
48.7 x 10-3cm2/sec
1800°F
7.9 x 10-3in2/sec
1000°C
51.6 x 10-3cm2/sec
2000°F
8.3 x 10-3in2/sec
Thermal Conductivity 70°F
72 Btu-in/ft2-h-°F
25°C 10.5 W/m-°C
125°F
77 Btu-in/ft2-h-°F
100°C 12.0 W/m-°C
200°F
83 Btu-in/ft2-h-°F
200°C 14.0 W/m-°C
400°F
99 Btu-in/ft2-h-°F
300°C 15.9 W/m-°C
600°F
114 Btu-in/ft2-h-°F
400°C 17.7 W/m-°C
800°F
127 Btu-in/ft2-h-°F
500°C 19.5 W/m-°C
1000°F
140 Btu-in/ft2-h-°F
600°C 21.2 W/m-°C
1200°F
152 Btu-in/ft2-h-°F
700°C 22.9 W/m-°C
1400°F
165 Btu-in/ft2-h-°F
800°C 24.5 W/m-°C
1600°F
178 Btu-in/ft2-h-°F
900°C 26.0 W/m-°C
1800°F
191 Btu-in/ft2-h-°F
1000°C 27.5 W/m-°C
2000°F
201 Btu-in/ft2-h-°F
Specific Heat 70°F 0.096 Btu/lb.-°F 25°C 403 J/kg-°C
125 °F 0.098 Btu/lb.-°F 100 °C 424 J/kg-°C
200 °F 0.101 Btu/lb.-°F 200°C 445 J/kg-°C
400 °F 0.106 Btu/lb.-°F 300°C 455 J/kg-°C
600°F 0.111 Btu/lb.-°F 400°C 462 J/kg-°C
800°F 0.116 Btu/lb.-°F 500°C 495 J/kg-°C
1000°F 0.119 Btu/lb.-°F 600°C 508 J/kg-°C
1200°F 0.123 Btu/lb.-°F 700°C 582 J/kg-°C
1400°F 0.128 Btu/lb.-°F 800°C 592 J/kg-°C
1600°F 0.137 Btu/lb.-°F 900°C 596 J/kg-°C
180 °F 0.143 Btu/lb.-°F 1000°C 598 J/kg-°C
2000°F 0.142 Btu/lb.-°F
Mean Coefficient of Thermal Expansion 70 - 200°F 7.1 µin/in.-°F 25 - 100°C 12.8 µm/m-°C
70 - 400°F 7.3 µin/in.-°F 25 - 200°C 13.1 µm/m-°C
70 - 600°F 7.5 µin/in.-°F 25 - 300°C 13.3 µm/m-°C
70 - 800°F 7.7 µin/in.-°F 25 - 400°C 13.7 µm/m-°C
70 - 1000°F 7.9 µin/in.-°F 25 - 500°C 14.0 µm/m-°C
70 - 1200°F 8.2 µin/in.-°F 25 - 600°C 14.6 µm/m-°C
70 - 1400°F 8.6 µin/in.-°F 25 - 700°C 15.1 µm/m-°C
70 - 1600°F 8.9 µin/in.-°F 25 - 800°C 15.8 µm/m-°C
70 - 1800°F 9.2 µin/in.-°F 25 - 900°C 16.2 µm/m-°C
70 - 2000°F 9.5 µin/in.-°F 25 - 1000°C 16.7 µm/m-°C
Dynamic Modulus of Elasticity RT
32.6 x 106psi
RT 225 GPa
200°F
32.3 x 106psi
100°C 222 GPa
400°F
31.0 x 106psi
200°C 214 GPa
600°F
29.4 x 106psi
300°C 204 GPa
800°F
28.3 x 106psi
400°C 197 GPa
1000°F
26.9 x 106psi
500°C 188 GPa
1200°F
25.8 x 106psi
600°C 181 GPa
1400°F
24.3 x 106psi
700°C 174 GPa
1600°F
22.8 x 106psi
800°C 163 GPa
1800°F
21.4 x 106psi
900°C 154 GPa
1000°C 146 Gpa

RT = Room Temperature

Wear Resistance

HAYNES® 25 alloy exhibits excellent resistance to metal galling and cavitation. Metal-to-Metal Galling results shown below were generated for standard matching material room-temperature pin on disc tests. Wear depths are given as a function of applied load. Cavitation tests were performed in accordance with ASTM G 32 water at 16°C, with a frequency of 20 kHz and an amplitude of 0.05 mm.  The results of the wear tests indicate that 25 alloy is superior in galling and cavitation resistance to many materials, and is surpassed only by ULTIMET® alloy and HAYNES® 6B alloy. Both of these materials were specifically designed to have excellent wear resistance.

Alloy Galling – Degree of Damage for Various Applied Loads
3,000 lbs. (1,365 kg) 6,000 lbs. (2,725 kg) 9,000 lbs. (4,090 kg)
mils µm mils µm mils µm
6B 0.02 0.6 0.03 0.7 0.02 0.5
ULTIMET® 0.11 2.9 0.11 2.7 0.08 2.0
25 0.23 5.9 0.17 4.2 0.17 4.2
188 1.54 39.2 3.83 97.3 3.65 92.6
HR-160® 1.73 43.9 4.33 109.9 3.81 96.8
214® 2.32 59.0 3.96 100.5 5.55 141.0
556® 3.72 94.4 5.02 127.6 5.48 139.3
230® 4.44 112.7 7.71 195.8 8.48 215.5
HR-120® 6.15 156.2 7.05 179.0 10.01 254.2
Alloy Cavitation – Mean Depth of Erosion
24 h 48 h 72 h 96 h
mils µm mils µm mils µm mils µm
ULTIMET® 0.3 6.8 0.9 22.9 1.6 40.2 2.3 57.4
6B 0.3 7.7 0.9 22.3 1.4 34.8 1.9 48.0
25 1.0 24.4 2.1 53.6 3.4 85.6 4.5 115.1
625 3.1 80.0 7.0 176.6 10.2 259.2 Not tested Not Tested
556® 3.3 83.8 6.9 175.8 9.6 244.3 11.4 289.8
230® 3.8 97.6> 7.5 190.1 9.9 251.8 11.9 301.7

Tested in accordance with ASTM G 32 water at 16ºC, with a frequency of 20 kHz and an amplitude of 0.05 mm

High-temperature Hardness

The following are results from standard vacuum furnace hot hardness tests. Values are given in originally measured DPH (Vickers) units and conversions to Rockwell C/BW scale in parentheses.

Vickers Diamond Pyramid Hardness (Rockwell C/BW Hardness)
70°F (20°C) 800°F (425°C) 1000°F (540°C) 1200°F (650°C) 1400°F (760°C)
Solution Treated 251 22 HRC 171 87 HRBW 160 83 HRBW 150 80 HRBW 134 74 HRBW
15% Cold-Work 348 35 HRC 254 23 HRC 234 97 HRBW 218 95 HRBW
20% Cold-Work 401 41 HRC 318 32 HRC 284 27 HRC 268 25 HRC
25% Cold-Work 482 48 HRC 318 32 HRC 200 30 HRC 286 28 HRC

HRC = Hardness Rockwell “C”.
HRBW = Hardness Rockwell “B”, Tungsten Indentor.

Aqueous Corrosion Resistance

HAYNES® 25 alloy was not designed for resistance to corrosive aqueous media. Representative average corrosion data are given for comparison. For applications requiring corrosion resistance in aqueous environments, ULTIMET® alloy and HASTELLOY® corrosion-resistant alloys should be considered.

Alloy Average Corrosion Rate, per year
1% HCl (Boiling)
10% H2SO4 (Boiling)
65% HNO3 (Boiling)
mils mm mils mm mils mm
ULTIMET® <1 <0.03 99 2.51 6 0.15
C-22® 3 0.08 12 0.30 134 3.40
25 226 5.74 131 3.33 31 0.79
316L 524 13.31 1868 47.45 9 0.23

Oxidation Resistance

HAYNES® 25 alloy exhibits good resistance to both air and combustion gas oxidizing environments, and can be used for long-term continuous exposure at temperatures up to 1800°F (980°C). For exposures of short duration, 25 alloy can be used at higher temperatures. Applications for which oxidation resistance is a serious consideration normally call for newer, more capable materials such as 230® alloy or HAYNES 188 alloy. This is particularly important at temperatures above 1800°F (980°C).

Comparative Burner Rig Oxidation Resistance
1000 Hour Exposure at 1800°F (980°C), 30 minute Cycles

Alloy Metal Loss Average Metal Affected Maximum Metal Affected
mils μm mils μm mils μm
188 1.1 28 3.2 81 3.9 99
230® 2.8 71 5.6 142 6.4 163
617 2.4 61 5.7 145 6.9 175
625 3.7 94 6.0 152 6.6 168
X 4.3 109 7.3 185 8.0 203
5 7.8 198 9.8 249 10.3 262
310SS 16.0 406 18.3 465 19.5 495
800H 22.9 582 Internal oxidation through thickness

Oxidation Test Parameters

Burner rig oxidation tests were conducted by exposing samples 3/8 in. x 2.5 in. x thickness (9 mm x 64 mm x thickness), in a rotating holder, to products of combustion of No. 2 fuel oil burned at a ratio of air to fuel of about 50:1. (Gas velocity was about 0.3 mach). Samples were automatically removed from the gas stream every 30 minutes and fancooled to near ambient temperature and then reinserted into the flame tunnel.

Comparative Burner Rig Oxidation Resistance at 2000°F (1095°C) for 500 Hours

Alloy Average Metal Loss per Side Maximum Metal Affected
mils μm mils μm
214® 1.2 30.5 1.8 45.7
230® 7.1 180.3 11.8 299.7
188 10.9 276.9 14.1 358.1
X 11.6 294.6 15.1 383.5
25 > 25* >635*

*25 mils (635 µm) in 165 hours

Comparative Oxidation Resistance in Flowing Air*

Alloy 1800°F (980°C) 2000°F (1095°C) 2100°F (1150°C)
Average Metal Affected Metal Loss Average Metal Affected Metal Loss Average Metal Affected Metal Loss
mils μm mils μm mils μm mils μm mils μm mils μm
188 1.1 28 0.1 3 3.7 94 0.5 13 10.7 272 8.6 218
230® 1.5 38 0.2 5 3.3 84 0.5 13 4.4 112 1.2 30
25 2.0 51 0.3 8 10.2 259 9.2 234 10.7 272 8.2 208
X 1.5 38 0.2 5 4.4 112 1.3 33 6.1 115 3.6 91
625 1.9 48 0.4 10 7.8 198 3.5 89 20.2 513 18.3 465
617 2.0 51 0.3 8 3.8 97 0.6 15 5.2 132 1 25
800HT 4.1 104 0.5 13 11.6 295 7.6 193 15.0 381 11 279

*Flowing air at a velocity of 7.0 ft/min (213.4 cm/min) past the samples. Samples cycled to room temperature once per week.
**Average Metal Affected = Metal Loss + Average Internal Penetration

Sulfidation Resistance

Sulfidation Resistance at 1400°F (760°C)

HAYNES® 25 alloy has very good resistance to gaseous sulfidation environments encountered in various industrial applications. Tests were conducted at 1400°F (760°C) in a gas mixture consisting of AR – 5% H2 – 5% CO – 1% CO2 – 0.15% H2S, balance Ar. Coupons were exposed for 215 hours. This is a severe test, with equilibrium sulfur partial pressure of 10-6 to 10-7 and oxygen partial pressures less than that needed to produce protective chromium oxide scales.

 

Schematic Representation of Metallographic Technique Used for Evaluating Environmental Tests

Fabrication

HAYNES® 25 alloy has good forming and welding characteristics. It may be forged or otherwise hot-worked, providing that it is held at 2200°F (1205°C) for a time sufficient to bring the entire piece to temperature. The alloy has good ductility, and thus also may be formed by cold working. The alloy does work-harden very rapidly, however, so frequent intermediate annealing treatments will be needed for complex component forming operations. All hot- or cold-worked parts should be annealed and rapidly cooled in order to restore the best balance of properties. The alloy can be welded by both manual and automatic welding methods, including gas tungsten arc (GTAW), gas metal arc (GMAW), shielded metal arc, electron beam and resistance welding. It exhibits good restraint welding characteristics.

Heat Treatment

HAYNES® 25 alloy is furnished in the solution heat-treated condition, unless otherwise specified.  The alloy is normally final solution heat-treated at 2150 to 2250°F (1175 to 1230°C) for a time commensurated with section thickness and rapidly cooled or water-quenched for optimal properties. Because annealing at temperatures less than the solution heat-treating temperature will produce some carbide precipitation in 25 alloy, which may affect the alloy’s properties, annealing during fabrication may be performed at lower temperatures, but a final, subsequent solution heat treatment is needed to produce optimum properties and structure.

Machining

For information on Machining, please refer to the machining section of Welding and Fabrication.

Effect of Cold Reduction Upon Room-Temperature Properties*

Cold Reduction Subsequent Anneal 0.2% Yield Strength Ultimate Tensile Strength Elongation Hardness
% None ksi MPa ksi MPa % HRC
0 68.4 470 144.0 995 58.5 24
10 123.6 850 181.9 1255 37.1 36
15 148.5 1025 178.2 1230 27.7 40
20 150.9 1040 193.5 1335 18.2 42
25 183.9 1270 232.5 1605 14.6 44
10 1950°F (1065°C) for 5 min. 97.9 675 163.0 1125 39.3 32
15 91.2 630 167.1 1150 43.8 30
20 96.5 665 170.7 1175 40.8 32
25 88.9 615 169.5 1170 44.3 32
10 2050°F (1120°C) for 5 min. 74.0 510 156.6 1080 53.4 27
15 78.6 540 161.2 1110 51.9 28
20 82.0 565 164.8 1135 47.6 31
25 82.9 570 165.6 1140 48.0 30
10 2150°F (1117°C) for 5 min. 66.9 460 148.1 1020 62.6 21
15 73.6 505 156.1 1075 55.4 26
20 72.1 495 154.0 1060 59.3 26
25 68.5 470 149.3 1030 61.7 25

*Based upon cold reductions taken upon 0.110-inch (2.8 mm) thick sheet. Duplicate tests.
HRC = Hardness Rockwell “C”.

Welding

HAYNES® 25 alloy is readily welded by Gas Tungsten Arc (GTAW), Gas Metal Arc (GMAW), Shielded Metal Arc (SMAW), electron bean welding, and resistance welding techniques. Its welding characteristics are similar to those of HAYNES® 188 alloy. Submerged Arc welding is not recommended, as this process is characterized by high heat input to the base metal and slow cooling of the weld. These factors can increase weld restraint and promote cracking.

Base Metal Preparation

The joint surface and adjacent area should be thoroughly cleaned before welding. All grease, oil, crayon marks, sulfur compounds, and other foreign matter should be removed. Contact with copper or copper-bearing materials in the joint area should be avoided. It is preferable, but not necessary, that the alloy be in the solution-annealed condition when welded.

Filler Metal Selection

Matching composition filler metal is recommended for joining alloy 25. For shielded metal arc welding, HAYNES® 25 alloy electrodes (AMS 5797) are suggested. For dissimilar joining of 25 alloy to nickel-, cobalt-, or iron- base materials, 25 alloy itself (AMS 5796), 230-W® filler wire(AMS 5839), HAYNES® 556® alloy (AMS 5831), HASTELLOY® S alloy (AMS 5838), or HASTELLOY® W alloy (AMS 5786) welding products are suggested, depending upon the particular case. Please click here or see the Haynes Welding SmartGuide for more information.

Preheating, Interpass Temperatures, and Postweld Heat Treatment

Preheat is not required. Preheat is generally specified as room temperature (typical shop conditions). Interpass temperature should be maintained below 200°F (93°C). Auxiliary cooling methods may be used between weld passes, as needed, providing that such methods do not introduce contaminants. Postweld heat treatment is not generally required for 25 alloy. For further information, please click here.

Welded Tensile – Room Temperature

Form 0.2% Yield Strength Ultimate Tensile Strength Elongation
ksi MPa ksi MPa %
Sheet 69.0 476 144.5 996 54.7
Plate 68.7 474 145.1 1000 58.8
Welded Transverse, GTAW 72.4 499 134.2 925 36.5
All Weld Metal, SMAW 88.6 611 141.0 972 31.5