Analysis of The Surface Roughness in Lapping Process Affecting Wear Behavior Based on The Bearing Area Curve Theory

Abstract

This paper presents an analysis of the surface morphology, and the constituent parameters of the Bearing Area Curve (BAC), which include reduced peak height (Rpk), core roughness depth (Rk), reduced valley depth (Rvk), material ratio at the peak zone (Mr1), and material ratio at the valley zone (Mr2), in conjunction with the arithmetic mean deviation (Ra). The study focuses on SKD61 tool steel, hardened to a hardness range of 52–55 HRC using vacuum hardening, and processed through a lapping process with four different alumina abrasive sizes: 0.05, 0.30, 1.00, and 3.00 micrometers, under oil–based diamond lapping lubricant conditions. The BAC analysis was employed to guide the selection of optimal surface characteristics for improved wear resistance. The analysis results revealed that SKD61 tool steel lapped with a 0.30 micrometer alumina abrasive size exhibited a short run–in period and a large contact area (high Rk), which reduces the load per unit area, leading to enhanced wear resistance.