Elevated temperature mechanical testing of wire arc additively manufactured austenitic stainless steel

Wire arc additive manufacturing (WAAM), a metal 3D printing technique, is attracting increasing attention from the construction industry due to its high efficiency, cost-effectiveness and flexibility in build scales. Test data on the mechanical properties of WAAM stainless steel in fire conditions are however limited. To address this gap, an experimental study into the elevated temperature material properties of WAAM ER316LSi austenitic stainless steel has been conducted. A total of 30 tensile coupons, consisting of 20 as-built coupons and 10 machined coupons, were tested at both room temperature and elevated temperatures. Steady-state tensile testing of the WAAM coupons was conducted in the elevated temperature range of 100 °C to 900 °C with intervals of 100 °C. 3D laser scanning was applied to obtain the geometric properties of the as-built coupons. The elevated temperature mechanical properties and the corresponding reduction factors were derived from the tensile test results. Finally, the elevated temperature material model in EN 1993-1-2, originally developed for conventionally produced stainless steel, was shown to be also applicable to WAAM stainless steel. • Elevated and room temperature tensile tests on 30 WAAM stainless steel coupons. • Use of 3D laser scanning for determining the specimen geometries. • Effect of surface undulations inherent to WAAM on examined material properties. • Development of reduction factors for key mechanical properties. • Proposal of elevated temperature constitutive model for WAAM stainless steel.