Investigation of wear behavior of borided dın x15crnisi25 steel

Abstract

In the present study, effect of the boriding process on adhesion and tribological properties of DIN X15CrNiSi25 steel has been investigated. Boriding was performed in a solid medium consisting of Ekabor- II powders at 1123 and 1323K for 2 and 6 h. The boride layer was characterized by optical microscopy, Xray diffraction technique and the micro-Vickers hardness tester. . X-ray diffraction analysis of boride layers on the surface of the steels revealed the existence of FexBy, CrxBy and NixBy compounds. Depending on the chemical composition of substrates, the boride layer thickness on the surface of the X15CrNiSi25 steel was found to be 56.74 μm. The hardness of the boride compounds formed on the surface of the X15CrNiSi25 steel ranged from 1658 to 2284 HV0,1, whereas Vickers hardness values of the untreated steel X15CrNiSi25 were 276 HV0,1. The wear tests were carried out in a ball-disc arrangement under a dry friction condition at room temperature with an applied load of 10N and with a sliding speed of 0.3 m/sec at a sliding distance of 1000m. The wear surfaces of the steel were analyzed using a SEM microscopy and X-ray energy dispersive spectroscopy EDS. It was observed that the wear rate of unborided and borided X15CrNiSi25 steel ranged from 4.57 to 71.42 mm3/Nm.