Form This specification covers a precipitation hardenable@ corrosion and heat-resistant nickel alloy in the form of seamless tubing 0.125 inch (3.18 mm) and over in nominal OD and 0.015 inch (0.38 mm) and over in nominal wall thickness (see 8.5). Application This tubing has been used typically for fluid lines requiring high strength up to 1300 ??(704 ?? and oxidation resistance up to 1800 ??(982 ??@ but usage is not limited to such applications. Parts may be formed and then heat treated to improve strength at elevated temperatures.