Surface crack propagation of electroplated chromium coating and cotton fabric with dry friction

Abstract

Electroplated chromium coatings are commonly used to improve the wear resistance of metal parts in the cotton textile industry, and surface crack is an important feature. This study investigates the tribological properties and surface crack propagation of the electroplated chromium coating in dry friction contact with cotton fabric. It is found that the coating has excellent tribological properties, with the friction coefficient eventually stabilized at 0.11 and the average wear rate of 0.0038 mm3/h. The cotton fabric mainly exhibits a polishing effect on the coating during friction, and the failure of the coating is in the form of delamination failure within the coating. Crack propagation is mainly due to the friction of cotton fabric, the main cracks of the mesh crack structure hardly propagate, while the short cracks extending on the main cracks undergo propagation behavior. Short cracks propagate vertically along the friction direction and eventually develop into the main crack level. The tangential stress generated by friction acts on the crack tip, which is the main cause of crack propagation. The plastic zone generated at the crack tip affects the distribution of the stress field and the effect of the plastic zone on crack propagation is analyzed.