Optimization of Mass Loss During Abrasive Wear of Nitrided AISI 4140 Steel Parts

This study aims to reduce the wear of parts made of gas nitrided AISI 4140 steel. This steel has mechanical and physical characteristics superior to most conventional materials, with a very high hardness after gas nitriding. AISI 4140 steels are often subjected to abrasive wear tests, which can result in mass loss. Efforts are therefore necessary to reduce this degradation. An in-depth optimization study is proposed to examine the effects of the hardness of the steel, the normal load, and the speed of wear. Tools such as experimental designs and analysis of variance are used to decipher the impact of each factor on the response variable studied and identify the predominant factors. Among these factors, the normal load is the most significant, with a lower load resulting in less mass loss. Hardness is the second most significant factor, Speed is the least. The hardness also has an interaction effect with the other two factors, which reduces mass loss. The optimal conditions retained are a normal load of 100 N, a Speed of 4.18 m/s, and a Hardness of 1092 HV.