Characterising the high temperature tensile behaviour of laser powder bed fused duplex stainless steel 2205 using the small punch test

Duplex stainless steels (DSS) are a family of stainless steel alloys that benefit from the presence of two relatively equally proportioned phases, ferrite and austenite. The alloys are designed to have an enhanced resistance to corrosion and superior strength properties in comparison to more common stainless steel alloys such as 316 L. Design engineers are now exploring the introduction of additively manufactured (AM) DSS into industrial components, to benefit from these enhanced capabilities provided by the alloy and the greater flexibility in design offered by AM. This research focuses on the mechanical and microstructural characterisation of DSS 2205, manufactured by the AM process laser powder bed fusion (LPBF). Results have been generated through both uniaxial tensile testing and small punch (SP) testing on as built and heat-treated conditions, across a range of temperatures up to 750 °C. Microstructural assessments have been conducted using advanced microscopy to determine relevant phase distributions and texture morphologies present in the materials, to understand how this influences mechanical performance.