Damage characteristics of laser-material interaction in AlLiCuMg alloys

Abstract

The hardening of two-component alloys of AlLi type is achieved by thermal precipitation, and of much practical importance are the three-component alloy group AlMgLi and multi-component AlLiCuSiMg. They possess lower values for specific weight and higher values for Young’s modulus compared to conventional aluminum alloys. Therefore, owing to their widely extended application in aircraft industry, an attempt for investigating and improving their characteristics is reasonable. In this paper an AlLiCuSiMg alloy was exposed to ruby-laser radiation, λ = 0.694 μm, 2x10exp(–6) s and 3x10exp(–8) s pulsing, and energy variations from 0.14 to 2.6 J. Scanning electron microscopy analysis of the structure has shown defined damages in the tested material. Shallow and deep craters have been observed and crater diameters have been determined. The main purpose of this investigation is to determine the differences of micro-damages in the material as a function of thermomechanical treatment. The influence of time dependent power densities (energies) was also studied.