Behavior evaluation and effects of different lubricants in ECAP process

Abstract

Purpose The purpose of equal channel angular pressing (ECAP) is producing ultra-fine grain materials. In practical applications, it is important to understand and predict effect of different process parameters on deformed parts. One of the most important process parameters is friction coefficient. Behavior evaluation of different lubricants in the ECAP process is the aim of this research. Design/methodology/approach The present study concerns the experimental measurements of the effective strain by means of gridded parts for three different lubricants, graphite, molybdenum disulfide and zinc stearate, to evaluate friction coefficient in ECAP process. Mesh size was 2 × 2 mm2 and embedded in parts made of AL2024; process was done in ambient temperature, and parts were in annealed situation. After the process, strain measured by optical and analytical methods for evaluation of lubricants’ behavior with different friction coefficients. Findings This study shows that zinc stearate has better effects rather than other lubricants in ECAP process and ECAPed parts. Originality/value The fatal challenge for researchers and industrial applications of ECAP process is lubrication. This research is a guide for scientists and engineers (in the future applications) to reduce and control bad frictional effects, produce better parts (more strain homogenous parts), prevent die failures and decrease press tonnage in ECAP process.