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Plastic deformation and strain-induced martensite (SIM, α 1 ) transformation in metastable austenitic AISI 304 stainless steel were investigated through room temperature tensile tests at strain rates ranging from 2ˆ10´6 to 2ˆ10´2/s. The amount of SIM was measured on the fractured tensile specimens using a feritscope and magnetic force microscope. Elongation to fracture, tensile strength, hardness, and the amount of SIM increased with decreasing the strain rate. The strain-rate dependence of RT tensile properties was observed to be related to the amount of SIM. Specifically, SIM formed during tensile tests was beneficial in increasing the elongation to fracture, hardness, and tensile strength. Hydrogen suppressed the SIM formation, leading to hydrogen softening and localized brittle fracture.

High-purity, dense nano-laminated (Cr0.95Ti0.05)2AlC compounds were synthesized via a powder metallurgical route. Their oxidation characteristics were investigated by exposing them to temperatures between 900 and 1200 degrees C in air. The alloying Ti in the Cr layer of Cr2AlC did not significantly change the crystal structure and microstructure of Cr2AlC. But, it increased the oxidation rate of the Cr,AlC. The scale morphology of the (Cr0.95Ti0.05)2AlC was basically similar to that of the pure Cr2AlC. The main difference was that the (Cr0.95Ti0.05)2AlC contained oxide nodules. These formed because the titanium oxidized to TiO2, making the Cr2AlC susceptible to nodular oxidation. However, alpha-Al2O3 was still the major oxidation product in both the (Cr0.95Ti0.05)2AlC and pure Cr2AlC.