Investigation of Milling-Induced Effects on the Fatigue Life of S2-Glass Composite Structures through Experimental Study and Statistical Optimization of Machining Conditions

Abstract

The machining of fiber-reinforced polymers (FRP) has been a challenge, as it plays a crucial role in determining the material's performance. Milling is commonly used to trim natural and synthetic FRP, causing various types of damage that significantly affect the material's mechanical properties. In the present study, the influence of milling parameters, cutting speed, feed rate, cutting direction, and tool surface on the fatigue life of S2-GFRP is investigated using Taguchi and ANOVA analyses. Findings indicate that the fatigue life of S2-GFRP is within the range of 7.8 & times; 104 and 14.4 & times; 104 cycles at a strain ratio of 0.4 in tension-tension fatigue testing. Cutting speed significantly affects fatigue life, followed by a moderate effect of the cutting direction. An 82.9% increase in the fatigue life of S2-GFRP is observed when machined at 750 rpm and 0.2 mm rev-1 in the climb direction cutting with an aluminum nitride-coated tool surface.