Experimental analysis of dynamic behavior of instruments in the process of friction stir welding

Abstract

The process of friction stir welding of metal materials is followed by numerous and complex thermal, mechanical, and tribological phenomena. The structure of a welding joint most highly depends on the geometry of the instrument as a technological parameter, i.e., its dynamic response, which is the result of deformation resistance of basic material during simultaneous rotary-translatory motion of the instrument through the object being welded. This paper presents a fragment of comprehensive experimental measurements and tests relevant for assessing the dynamic behavior of instruments during different phases and cycles of welding of the high-strength aluminum alloy of complex phase composition EN AW 7049A in the T652 state. The applied model of continuous monitoring of pressure force and the three-axis component of vibration acceleration in the frequency domain is a basis for forming a technological process suitable for prediction of impact factors on the welding process.