Effect of Carbide Precipitation on Hardness and Wear Resistance of H13 Steel

The carbide precipitation of H13 steel and its effect on hardness and friction and wear resistance are investigated by microstructure observation, phase analysis, and mechanical property test. Results show that the tempering hardness is mainly related to the content of secondary carbides. After solution treatment in the temperature range of 1040–1070 °C, quenching and tempering, with the increase of the solution temperature, the content of secondary carbides and hardness of H13 steel in the tempering microstructure increase first and then decrease, and both reach the maximum value when the solution temperature is 1060 °C. The change of hardness is consistent with that of the content of secondary carbides. When the solution temperature is 1040 °C, the wear mass loss of the tempered H13 steel is the least, which is 4.63 mg, indicating that its wear resistance is the best, and this is caused by the presence of more undissolved carbides in the tempering microstructure. With the increase of the solution temperature, the wear mass loss increases gradually, and the wear resistance decreases, which is mainly related to the content decrease of undissolved and secondary carbides and the content increase of residual austenite.