Temper Tough® is an air melted, cobalt-free, high-strength, high-toughness quenched and tempered alloy. It attains a typical 290 ksi (1999 MPa) UTS combined with a typical range of 60-65 ksi sqrt(in.) (66-71 MP sqrt(m)) fracture toughness. Temper Tough® is not a stainless alloy and may require plating or coating with a rust preventative or oil to prevent corrosion. The KIscc (as measured in a Rising Step Load Test) of Temper Tough alloy is 11.0 ksi sqrt(in.) (12.1 MPa sqrt(m)) in a 3.5% NaCl solution.