Fatigue and fracture characterisation of copper-brazed 316L stainless steel

• Fatigue and fracture behaviour of copper-brazed 316L stainless steel is investigated. • The fatigue-life curve of copper-brazed 316L stainless steel is obtained • The comprehensive fractographic analysis of fractured surfaces is proposed. • The obtained experimental results may be beneficial for designing copper-brazed plate heat exchangers. This study focuses on the mechanical, fatigue and metallographic characterisation of copper-brazed 316L stainless steel for the potential use in different plate heat exchangers (PHE) applications. The quasi-static and fatigue tests have been performed on the specially designed copper-brazed tensile specimens to obtain the engineering stress–strain diagram and the fatigue life curve of the analysed brazed joint. Furthermore, a comprehensive metallographic investigation has been done, focusing on (i) material characterisation of as-received stainless steel 316L, (ii) characterisation of the brazed joint and (iii) fractographic analyses of fractured surfaces by quasi-static and fatigue loading. The obtained experimental results may be beneficial for designing copper-brazed plate heat exchangers in the future.