High carbon steel is characterized by good toughness and high hardness, especially after an appropriate heat treatment. In this work heat treatment of 0.75% carbon steel with 4.50 % Mo, including heating to a different austenitic phase (850, 900 and 950oC) and holding for different times (30 min and 1 hour), then cooling by different media. The results shows no noticeable increase in the hardness at 850oC, but at 900oC changing in hardness values can be observed clearly with oil and water quenched specimens, at 950oC there is a big changing in hardness values in all quenching medium even at air and furnace cooling, the hardness values. As Austenization temperature increase the hardness of the samples increase especially for samples cooled with oil and water at 950oC. Tests showed that the microstructure contain carbides, that carbides did not completely melted even using a 1050oC due to percentage of molybdenum which produce stable carbides until melting.
Ključne reči :
Tematska oblast:
Mehanika i konstrukcije
Datum:
05.12.2012.
Br. otvaranja:
470
