Alloy |
UNS Number |
Waspaloy |
UNS N07001 |
GENERAL PROPERTIES
Waspaloy is a precipitation hardening, nickel-based alloy which has been used in elevated temperature applications. The alloy has been used for gas turbine engine parts which require considerable strength and corrosion resistance at temperatures up to 871°C (1600°F). Waspaloy is usually vacuum-induction plus consumable electrode re-melted.
RESISTANCE TO CORROSION
Waspaloy has excellent resistance to corrosion by combustion products, encountered in gas turbines and aircraft jet engines, at temperatures up to 871°C. Intergranular oxidation occurs at temperatures above 871°C.
PHYSICAL PROPERTIES
Melting Point (°C) |
Density |
Specific Gravity |
Modulus of Elasticity |
1330 – 1357 |
8.20g/cm3 |
8.25 |
211 GPa |
MECHANICAL PROPERTIES
Alloy |
Tensile Strength |
Yield Strength |
% Elongation |
Waspaloy |
150,000 |
85,000 |
25 |
CHEMICAL PROPERTIES
Alloy |
C |
Mn |
Si |
Cr |
B |
Fe |
Co |
Ti |
Al |
Mo |
Zr |
Cu |
S |
Ni |
W |
0.02-0.10 |
0.5 |
0.75 |
18.0-21.0 |
0.003-0.008 |
2.0 |
12.0-15.0 |
2.60-3.25 |
1.0-1.5 |
3.5-5.0 |
0.02-0.12 |
0.10 |
0.02 |
Bal |
WELDING
Waspaloy should always be in the annealed or solution treated condition before attempting welding. Good fit up and careful control of arc length and current input will minimize weld restraint. A clean surface is important-chemical descaling, cleaning solvents, vapour blasting (not sand blasting), and emery cleaning are recommended.
Any molten weld metal should be protected from atmospheric contamination. Argon is recommended for both sides of butt joints. Rapid cooling of the weld area is best practice. Copper back-up bars and /or water-cooled fixtures or sprays are recommended.
All welded parts should be re-solution treated. "Strain-age" cracking can be minimized by heating welded parts through the aging temperature as rapidly as possible.
HEAT TREATMENT
Special Metals Waspaloy is heat treated in a three-step sequence encompassing solution treatment, stabilization and age hardening.
- For optimum high-temperature creep and stress-rupture properties.
Solution treatment - heat at 1080°C (1975°F)/4h/AC to produce hardness of 20-25 Rockwell C.
Stabilization - reheat to 845°C (1550°F)/24h/AC.
Age harden - reheat to 760°C (1400°F)/16h/AC to produce hardness of 34-40 Rockwell C.
- For optimum room- and high-temperature tensile properties.
Solution treatment - heat at 995-1035°C (1825-1895°F)/4h/oil quench.
Stabilization - reheat to 845°C (1550°F)/4h/AC.
Age harden - reheat to 760°C (1400°F)/16h/AC to produce hardness of 34-44 Rockwell C.