The effect of machining on the surface integrity and fatigue life

Steel components often have to be machined after heat treatment in order to obtain the correct shape as well as the required surface finish. Surface quality influences characteristics such as fatigue strength, wear rate, corrosion resistance, etc. Hard turning allows manufacturers to simplify their processes and still achieve the desired surface finish quality. There are various parameters such as cutting speed, feed rate, and tool nose radius that are known to have a large impact on surface quality. This paper describes how feed rate and nose radius affect the surface integrity and fatigue life in turning. The results show that the effect of residual stress on fatigue life is more pronounced than the effect of surface roughness. The goal of this work is to identify a relationship between surface quality, turning process parameters and fatigue behavior of 34CrNiMo6.