Effect of Microstructural Variation on Erosion Wear Behavior of Ti-6Al-4V Alloy

Abstract

The present article describes the effect of microstructural variationsthat is, lamellar, bimodal, and equiaxedon solid particle erosion wear behavior of Ti-6AL-4V alloy at room temperature. Erosion tests were carried out at various test conditions using an air jet-type test rig and Taguchi's orthogonal array experimental design. The results indicated that impact velocity is the most significant controlling factor influencing the solid particle erosion wear of Ti-6Al-4V alloy followed by impact angle, microstructural variation, and size of erodent. The lamellar microstructure of Ti-6Al-4V alloy has excellent erosion resistance, followed by bimodal and equiaxed microstructures. Ploughing or pile-up leading to platelet formation was found to be the primary mechanism of material loss in erosion of Ti-6Al-4V alloy. This mechanism of material loss is independent of its microstructural variation. These results were determined after observation of the eroded surface under a scanning electron microscope. Optical microscopy, Rockwell hardness testing, and scanning electron microscopy were used to characterize the microstructures and eroded surfaces of the Ti-6Al-4V alloy in order to correlate the results obtained.