Achieving Optimum Mechanical Properties by Improving Austenizing Temperature and Time for 12Cr2NiWV Steel

12Cr2NiWV steel is a double phase ferritic-bainitic alloy which has remarkable resistance to brittleness when exposed to radioactive environment. In this study optimum austenizing temperature is determined by examining heat treatment behavior and mechanical properties of chromium-tungsten steels. Austenizing temperatures included 850, 880, 910, 950, 970, 1000 and 1030 oC for the duration of 1 hour, followed by quenching in oil. The best austenizing temperature was recognized to be 910 oC. Optimized austenizing time after heat treating for 0.5, 1, 3, 5, 10 and 20 hours at 910 oC indicated that the best austenizing time is 1 hour. This arrangement resulted in a hardness of 37 HRC with maximum strength of 1070 MPa. The percentage of elongation was 18% and the microstructure consisted of ferrite-bainite appearance with very fine and dispersed precipitates.

Keywords:

Chromium-Tungsten steels , Ferritic-Bainitic steels , Heat treatment , Duplex structure , Mechanical properties