Dry sliding friction and wear response of WC-Co hardmetal pairs in linearly reciprocating and rotating contact

摘要

This paper presents an experimental evaluation of friction and wear properties of WC-Co cemented carbides. A comparison is made between unlubricated rotating and linearly reciprocating pin-onplate sliding pairs. The plate specimens were WC-10wt%Co grades surface finished by polishing or sequential wire-EDM steps, whereas WC-6wt%Co pins were used as counter body. The tests were carried out at room temperature using a sliding speed of 0.30m/s and mean Hertzain contact pressures of 1.76 and 2.08 GPa, i.e., normal contact loads of 15N and 25N, respectively. The worn surfaces on plate samples were quantified in terms of 2–D wear profiles obtained by means of surface topography scanning equipment. Wear mechanisms such as polishing and abrasion were identified using optical microscopy. Inferior tribological characteristics for wire-EDM surface finish compared to polishing were found. Higher friction coefficient and wear levels were measured in unidirectional rotating sliding experiments compared to linearly reciprocating test conditions.