Nickels: 625
625 alloy provides exceptional oxidation and corrosion resistance, excellent strength and toughness, outstanding fatigue resistance, high formability and good weldability. It maintains its strength and toughness anywhere from cryogenic temperatures up to 2000° F. Because alloy 625 work hardens quickly, extensive cold forming may require annealing throughout the cold forming process. This alloy is often used in jet engines and other aerospace applications.