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 solutioning 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.
Sound fusion welds are dependent on cleanliness and good joint fit-up. Inert-gas-shielded arc
welding with a direct current power supply gives best results. Shielding gas should be used for
both the arc and back-up. The weld area should be kept cool by use of copper back-up bars or
Good resistance welds are made by using high tip pressures and short welding times. Clean and
well-fitted laying surfaces are essential. Wrought products except wire are normally furnished
solution heat-treated at 1975°F (1079°C), rapid quenched. Wire is normally mill annealed.
Mechanical properties can be tailored by selecting various combinations of solutioning 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 solutioning temperatures produce higher tensile strengths at temperatures up to
about 1700°F (927°C). The effect of solution heat treating temperature on tensile strength and
stress-rupture strength is shown on page 3.