Alloy C-263, 2.4650, Nimonic® alloy 263, Haynes® 263 - nickel alloy

Alloy C-263, 2.4650, UNS N07263, Nimonic® alloy 263, Haynes® 263 - nickel alloy according to DIN 17750, AMS 5886

Alloy C-263, 2.4650, UNS N07263, Nimonic® alloy 263 – description

Alloy C-263 (UNS N07263) is a high-temperature, precipitation-hardened, creep-resistant Ni-Cr-Co-Mo alloy. It is supplied in the annealed condition. It is recommended for service temperatures up to 850°C, but it resists oxidation up to 1000°C. It is easily weldable (no susceptibility to post-weld heat treatment cracking), has good fabrication characteristics, good wear resistance, and does not exhibit intermediate temperature tensile ductility.

Applications

Alloy C-276 is used in aero and industrial gas turbines for low-temperature combustion chambers, transition liners, exhaust cones and rings.

Physical and Tensile Properties

Room temperature physical properties:

• Density: 8.4 g/cm³
• Melting temperature: 1300-1360 °C
• Magnetic permeability: <1.001

High-Temperature Coefficient of Thermal Expansion, from 20°C to:

• 100°C: 10.7 μm/m⋅K
• 200°C: 12.0 μm/m⋅K
• 300°C: 12.5 μm/m⋅K
• 400°C: 13.0 μm/m⋅K
• 500°C: 13.5 μm/m⋅K
• 600°C: 14.1 μm/m⋅K
• 700°C: 14.9 μm/m⋅K
• 800°C: 15.9 μm/m⋅K
• 900°C: 17.2 μm/m⋅K
• 1000°C: 18.2 μm/m⋅K

Thermal Conductivity:

• 20°C: 11.7 W/m · K
• 100°C: 13.0 W/m · K
• 200°C: 14.7 W/m · K
• 300°C: 16.3 W/m · K
• 400°C: 18.0 W/m · K
• 500°C: 19.7 W/m · K
• 600°C: 21.4 W/m · K
• 700°C: 23.0 W/m · K
• 800°C: 24.7 W/m · K
• 900°C: 26.8 W/m · K
• 1000°C: 28.5 W/m · K

Electrical Resistivity:

• 20°C: 1.15 μΩ·m
• 100°C: 1.17 μΩ·m
• 200°C: 1.18 μΩ·m
• 300°C: 1.2 μΩ·m
• 400°C: 1.22 μΩ·m
• 500°C: 1.24 μΩ·m
• 600°C: 1.26 μΩ·m
• 700°C: 1.26 μΩ·m
• 800°C: 1.25 μΩ·m
• 900°C: 1.24 μΩ·m
• 1000°C: 1.24 μΩ·m

Specific Heat Capacity:

• 20°C: 426 J/kg⋅K
• 100°C: 447 J/kg⋅K
• 200°C: 472 J/kg⋅K
• 300°C: 497 J/kg⋅K
• 400°C: 523 J/kg⋅K
• 500°C: 548 J/kg⋅K
• 600°C: 573 J/kg⋅K
• 700°C: 598 J/kg⋅K
• 800°C: 624 J/kg⋅K
• 900°C: 649 J/kg⋅K
• 1000°C: 674 J/kg⋅K

Young's Modulus:

• 20°C: 222 GPa
• 100°C: 218 GPa
• 200°C: 212 GPa
• 300°C: 206 GPa
• 400°C: 198 GPa
• 500°C: 192 GPa
• 600°C: 184 GPa
• 700°C: 176 GPa
• 800°C: 165 GPa
• 900°C: 153 GPa
• 1000°C: 143 GPa

High-Temperature Mechanical Properties of alloy C-263 bars:

• 20°C:
  • Yield strength: 585 MPa
  • Tensile strength: 1004 MPa
  • Elongation: 45 %
  • Reduction of area: 41 %
• 100°C:
  • Yield strength: 550 MPa
  • Tensile strength: 958 MPa
  • Elongation: 44 %
  • Reduction of area: 44 %
• 200°C:
  • Yield strength: 520 MPa
  • Tensile strength: 911 MPa
  • Elongation: 44 %
  • Reduction of area: 47 %
• 300°C:
  • Yield strength: 505 MPa
  • Tensile strength: 880 MPa
  • Elongation: 45 %
  • Reduction of area: 50 %
• 400°C:
  • Yield strength: 490 MPa
  • Tensile strength: 849 MPa
  • Elongation: 46 %
  • Reduction of area: 51 %
• 500°C:
  • Yield strength: 500 MPa
  • Tensile strength: 834 MPa
  • Elongation: 46 %
  • Reduction of area: 52 %
• 600°C:
  • Yield strength: 490 MPa
  • Tensile strength: 819 MPa
  • Elongation: 43 %
  • Reduction of area: 50 %
• 700°C:
  • Yield strength: 495 MPa
  • Tensile strength: 772 MPa
  • Elongation: 27 %
  • Reduction of area: 34 %
• 800°C:
  • Yield strength: 460 MPa
  • Tensile strength: 587 MPa
  • Elongation: 15 %
  • Reduction of area: 26 %
• 900°C:
  • Yield strength: 145 MPa
  • Tensile strength: 232 MPa
  • Elongation: 34 %
  • Reduction of area: 58 %
• 1000°C:
  • Yield strength: 70 MPa
  • Tensile strength: 108 MPa
  • Elongation: 69 %
  • Reduction of area: 72 %

High-Temperature Mechanical Properties of alloy C-263 sheets:

• 20°C:
  • Yield strength: 580 MPa
  • Tensile strength: 973 MPa
  • Elongation: 39 %
• 100°C:
  • Yield strength: 515 MPa
  • Tensile strength: 896 MPa
  • Elongation: 40 %
• 200°C:
  • Yield strength: 500 MPa
  • Tensile strength: 849 MPa
  • Elongation: 41 %
• 300°C:
  • Yield strength: 475 MPa
  • Tensile strength: 834 MPa
  • Elongation: 42 %
• 400°C:
  • Yield strength: 470 MPa
  • Tensile strength: 816 MPa
  • Elongation: 43 %
• 500°C:
  • Yield strength: 490 MPa
  • Tensile strength: 803 MPa
  • Elongation: 43 %
• 600°C:
  • Yield strength: 490 MPa
  • Tensile strength: 788 MPa
  • Elongation: 41 %
• 700°C:
  • Yield strength: 475 MPa
  • Tensile strength: 757 MPa
  • Elongation: 23 %
• 800°C:
  • Yield strength: 440 MPa
  • Tensile strength: 556 MPa
  • Elongation: 20 %
• 900°C:
  • Yield strength: 135 MPa
  • Tensile strength: 201 MPa
  • Elongation: 49 %
• 1000°C:
  • Yield strength: 70 MPa
  • Tensile strength: 108 MPa
  • Elongation: 65 %

Stress Rupture requirements:

• 650°C, 100h: 531 MPa
• 650°C, 1000h: 441 MPa
• 705°C, 100h: 414 MPa
• 705°C, 1000h: 310 MPa
• 760°C, 100h: 290 MPa
• 760°C, 1000h: 193 MPa
• 815°C, 100h: 172 MPa
• 815°C, 1000h: 103 MPa
• 870°C, 100h: 97 MPa
• 870°C, 1000h: 51 MPa
• 930°C, 100h: 50 MPa
• 930°C, 1000h: 28 MPa

Creep Resistance - stress to produce 1% creep:

• 650°C, 100h: 517 MPa
• 650°C, 1000h: 400 MPa
• 705°C, 100h: 372 MPa
• 705°C, 1000h: 283 MPa
• 760°C, 100h: 255 MPa
• 760°C, 1000h: 172 MPa
• 815°C, 100h: 152 MPa
• 815°C, 1000h: 83 MPa
• 870°C, 100h: 76 MPa
• 870°C, 1000h: 41 MPa
• 930°C, 100h: 39 MPa
• 930°C, 1000h: 21 MPa

Thermal Stability - Ultimate tensile strength in a given temperature after staying in the temperature for the given time:

• 760°C, 0h: 689 MPa
• 760°C, 8000h: 577 MPa
• 815°C, 0h: 537 MPa
• 815°C, 8000h: 404 MPa
• 870°C, 0h: 341 MPa
• 870°C, 8000h: 176 MPa

Corrosion Resistance

Heat Resistance / High-Temperature Oxidation - good resistance up to 1000°C.

1008h long static oxidation test results (6 cycles per 168 h in flowing air):

• 870°C:
  • Metal loss: 3 μm
  • Average metal affected: 10 μm
• 925°C:
  • Metal loss: 5 μm
  • Average metal affected: 18 μm
• 980°C:
  • Metal loss: 23 μm
  • Average metal affected: 127 μm

The results of dynamic oxidation tests in the combustion gas (50 parts of air to 1 part of fuel) flowing at 0.3 mach. At the end of each 30 minutes cycle, samples were air cooled down to 260°C. In total, the samples spent 1000h in the combustion gas:

• 870°C:
  • Metal loss: 36 μm
  • Average metal affected: 102 μm
• 980°C:
  • Metal loss: 318 μm
  • Average metal affected: 409 μm

Weldability

Alloy 263 has improved weldability over alloy 80A. It can we welded with any common method. It is not susceptible to post-weld heat treatment cracking and heat-affected-zone cracking. The sources differ as to the pre-weld and post-weld heat treatment:

Haynes® 263 alloy datasheet says a post-weld heat treatment is required, and should consist of a solution anneal followed by an aging treatment.

Nimonic® alloy 263 datasheet states "a pre-weld heat treatment is not neccessary on age-hardened assemblies, but a subsequent age-hardening treatment is desirable after all salvage welding is completed. Materials will age in service if temperatures are above 750°C."

VDM Alloy C-263 datasheet says the material should be in the annealed condition before welding, and recommends diffusion annealing after welding.

Welding products: S NI 7263 / NiCo20Cr20MoTi, BS 2901 NA38, 2.4650

Heat Treatment, Working and Machining

Recommended work and heat treatment parameters:

• Hot working: 1170-950°C; water quench
• Solution-treatment: 1140-1160°C; rapid air cool / water quench
• Age-hardening: 785-815°C; 8h; air cool
• Intermediate annealing: 1070-1090°C; 4-6 min; air cool
• Homogenizing (treatment): 1150°C; 1h; air cool

During the final hot working operation, the temperature must not exceed 1120°C. The piece should be water-quenched.

We deliver this steel alloy as:

• Plates, strips and sheets according to AMS 5872, BS HR 206, AECMA PrEn 2203,2418, DIN 17750
• Bars, rods and forgings according to AMS 5886, BS HR 10, AECMA PrEn 2199,2201,2200, DIN 17752, DIN 17754
• Wires according to DIN 17753
• Pipes according to BS HR 404, DIN 17751, AECMA PrEn 2202

Replacements, equivalents and other designations:

AMS 5886, AMS 5966, Altemp 263, Nimonic® alloy 263, Nickelvac C-263, Udimet Ni90, Unitemp C-263, VDM Alloy C-263, Nicrofer 5120 CoTi, Haynes® 263, Alloy 263, Alloy C-263, N07263, 2.4650, NiCr20Co18Ti, BS HR 10, HR HR 206, BS HR 404, NW7263, NiCo20Cr20Mo5Ti2Al