Precipitation Hardening and Mechanical Properties in Cu Added Martensitic Ultra-high Strength Steels

High-Alloy Ferritic Steels: Martensitic Stainless Steels, Precipitation Hardening (code 1810)

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Strength of 10CR-N martensitic steels

lOCr stainless steel has been employed to examine the effect of nitrogen on microstructure and strength. Applying Solid state gaseous nitrogenising treatments a whole range of nitrogen martensite structures containing up to 0.45 wt% were obtained. It was found that a linear relationship exists between strength and nitrogen content in precipitate free martensitic structures. Yield strength incre...

Effect of strain rate and temperature on mechanical properties and fracture mode of high strength precipitation hardened ferritic steels

The effect of strain rate on the flow stress of a low carbon high strength ferritic steel that contains nanometer size Cu–Ni–Al precipitates is found to be much less than that of HSLA 65 that does not have such precipitates. This result is in agreement with the theory that such precipitates locally lower the Peierls stress for screw dislocations in body-centered cubic iron. The fracture mode in...

High-Strength Bainitic Steels

With careful design, mixed microstructures consisting of fine plates of upper bainitic ferrite separated by thin films of stable retained austenite have exhibited impressive combinations of strength and toughness in highsilicon bainitic steels. The silicon suppresses the precipitation of brittle cementite leading to an improvement in toughness. The essential principles governing the optimisatio...

Secondary Hardening in High Speed Steels