Incoloy products are mostly chromium-based and mostly nickel-based, and designed for corrosion resistance as well as strength at high temperatures.
Incoloy alloys belong to the category of super austenitic stainless steels. One advantage is that Incoloy alloys do not have to be heat treated after welding to restore the corrosion resistance.
There are specific alloys for resistance to particular chemical attacks. For example, alloy 020 is designed to be resistant to sulphuric acid, and the DS Incoloy is to be used in heat-treating furnaces with reactive atmospheres and many heat cycles.
Incoloy 908 “has high tensile strength, fatigue crack growth resistance, good weldability, metallurgical stability and ductility, high fracture and impact toughness, [and] low coefficient of thermal expansion… [Its] resistance to oxygen embrittlement… allows hot fabrication without cracking.
Incoloy 907 “has high strength and low thermal expansion coefficient at temperatures up to 800°F.” Incoloy 945X is designed for chlorine-rich environments. Molybdenum adds crevice corrosion and pitting to Incoloy 945.