Effect of Volume Fraction of Primary Alpha Phase on Solid Particle Erosion Behavior of Ti-6Al-4V Alloy

Abstract

The present article evaluates the influence of independent control factors such as percentage of primary alpha phase, impact velocity, impingement angle, and erodent size on solid particle erosion behavior of Ti-6Al-4V alloy using a statistical approach. Microstructural variation in terms of different percentage of primary alpha phase of investigated alloy has been introduced by solution annealing it at different temperatures followed by thermal aging. Solid particle erosion tests have been carried out using a sand blast-type test rig following an experimental schedule based on Taguchi's orthogonal arrays. It is observed that erosion rate and the value of percentage elongation decreased with an increase in the content of primary alpha phase from 10 to 20% and then increased for the value corresponding to the content of 30% primary alpha phase in this alloy. We observed that the solid particle erosion behavior of the investigated alloy consisting of various percentages of primary alpha phase is related to their ductility. Among all four control factors, impact velocity of the erodent has been found to be the most significant control factor influencing the solid particle erosion behavior of this alloy followed by impingement angle, percentage of primary alpha phase, and erodent size. Impact velocity has greatest static influence of 91.35%, impingement angle has an influence of 4.69%, percentage of primary alpha phase has an influence of 2.28%, and erodent size has an influence of 0.42% on solid particle erosion having R-2 = 0.99. Material loss during solid particle erosion of this alloy was found to be ductile in nature. Ploughing or pile-up leading to platelet formation is the primary mechanism of material loss during erosion of the alloy.