Process control, optimization and parameter characterization of mild steel single and multi-layer deposits using Wire + Arc Additive Manufacturing

Harley Stinson

Abstract

Wire + Arc Additive Manufacturing (WAAM) is a prom­ising technology for the manufacturing industry due its capacity to reduce material waste by up to 90% in certain applications whilst also providing a means of production for large-scale (<1m) metal structures with high deposition rates of up to 4kg/hr [1]. These comparatively higher rates of deposition and large build volumes allow WAAM to ful­fil manufacturing roles which its counterpart technologies such as Powder Bed Fusion would struggle to perform in an economical manner [1], [2]. The Automotive and Aerospace sectors are looking into WAAM as a prospective solution to fabricate large scale, medium complexity components with additional time and cost savings when compared to current subtractive and formative manufacturing methods [3]. Due to the energy sources employed, WAAM suffers from simi­lar defects observed in welding such as porosity, distortion, residual stresses, hot cracking etc. [4], [5]. This research will investigate the parameter settings and process controls (e.g. travel speeds and cooling rates) of WAAM Via Cold Metal Transfer (CMT) which can improve the mechanical proper­ties, microstructure and geometrical quality of WAAM Mild Steel single and multilayer specimens whilst minimising the presence of aforementioned defects. Testing will evaluate the tensile and flexural strength of machined specimens, fatigue life and microhardness throughout the multilayer deposits to characterise the effects of varying heat, current and volt­age inputs, deposition strategies, inter-layer cooling rates and travel speeds.

Relevant Publications in European Journal of Applied Engineering and Scientific Research