The effect of Tempering Temperature on Wear Behavior of AISI 5115 Steel Used in Spindles of Machine Tools

Wear is the main cause of reduced life expectancy and performance of spindle used in machine tools. To achieve high wear properties, the AISI 51XX series steel used as a spindle be applied in the carburized and tempered condition. In the current work, obtained properties from three different cycles of carburizing were compared with each other and the influence of tempering temperature on wear resistance of carburized samples were surveyed. The used wear test type was block on ring. Also, scanning electron microscopy, microhardness and metallography have been used for further investigation. The results show that; samples carburized at 920 °C for 5 hours, then normalized, next austenitized at 840 °C for 30 in, afterward quenched in oil and finally tempered at 100 °C has a good wear resistance compared with the other samples. Also, with increasing of tempering temperature to 250 °C, not only wear resistance of samples has not been improved, but also abrasion resistance, has been worsened rather to the raw samples.