Effect of Atmospheric Plasma Paint Removal on the Fatigue Performance of 2024-T3 Aluminium Alloy Sheet

Abstract

This article documents fatigue testing that was conducted using as-painted (baseline) and Atmospheric Plasma de-painted specimens made of 0.063 inch thick 2024-T3 aluminium alloy sheet. The intent of the test program was to determine whether AP de-painting would alter the fatigue properties of this aluminium substrate. AP de-painting process parameters were selected based on previous work that would remove the topcoat, while leaving most of the primer intact. This process was repeated five times to simulate service experience, where aircraft typically undergo five paint/de-paint cycles in their lifetime. As-painted (baseline) and five times de-painted specimens were fatigue tested under constant amplitude conditions, at two load ratios and several maximum stress levels. Ten samples per condition were used to establish statistical behaviour and repeatability. The test results and statistical analysis demonstrated that the selected AP process parameters did not have a detrimental effect on the fatigue performance of 2024-T3 aluminium alloy sheet.