Effects of deposition rate on local stability of Wire Arc additively manufactured outstand elements

Abstract

A great focus is currently being placed on the development of applications of Wire Arc Additive Manufacturing (WAAM) in structural engineering. To facilitate this development, an experimental programme investigating the effects of the deposition rate on WAAM 316LSi stainless steel outstand elements has been conducted. Equal angle section (EAS) stub columns with four different cross-sectional slendernesses were produced using WAAM. For each slenderness, four different deposition rates were employed; hence, overall, sixteen EAS stub columns were produced, 3D scanned and tested to examine their local stability. To keep the heat input constant between all cases, for each deposition rate, the travel speed was varied accordingly. Alongside the EAS specimens, tensile coupon testing was conducted to determine the material properties corresponding to each deposition rate. The tensile coupons were extracted at three different orientations (0°, 45° and 90°) relative to the deposition direction in order to investigate the degree of material anisotropy. In the present paper, following the description of the EAS stub column test results, the applicability of current Eurocode design rules and the Continuous Strength Method for the prediction of their design strength is assessed.