The effect of nickel, manganese, chromium, molybdenum, tungsten, titanium, vanadium, cobalt and silicon, each alloyirg up to 2%, on the austenitic grain size and its growth of 0.8%, C steel were studied by carburization method, heating at 850°, 925° and 1000° for 1, 2, 3, 4, 6 and 8 hours respeictively.
Manganese and cobalt increase the austenitic grain size and promote its growth by heating. Silicon has a small effect on the grain size and its growth in less content than 1.5%. Nickel, chromium, molybdenum and tungsten refine the brain size and the addition of these elements raise the coarsening temperature. The addition of vanadium or titanium is very effective; steels alloyed more than 0.3% of one of these two elements show very fine grain size, No. 9, and any grain growth is not observable even on heat at 1000° for 8 hours.
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