ISO/TR 4956:1984 pdf free.Wrought steels for use at elevated temperatures in engines. 1.1 This Technical Report covers technical delivery requirements and technical information for wrought steels supplied for parts such as bolts, blades, discs or casings in stationary or non-stationary turbines required to withstand relatively high mechanical Stresses at elevated temperatures (above about 400 °C) and additionally corrosive attack by...