Investigation on mechanical properties of Co-Cr-Mo alloy manufactured by selective laser melting

  • 1 Department of Mechanical Engineering, Ege University, İzmir, Turkey


Additive manufacturing approach is thought to be a key element to meet the needs of Industry 4.0. Selective laser melting (SLM) is a powder bed fusion additive manufacturing method for producing fully functional components. It is critical to determine the fatigue behavior of components produced by selective laser melting in order to fulfill the needs of industries with rigorous norms and criteria, such as the aviation industry. However, the rapid heating and cooling cycle caused by the nature of the SLM process has a negative mechanical effect on the components manufactured by this process.. Mechanical properties such as hardness and fatigue behavior should be disclosed for Co-Cr-Mo alloy manufactured by SLM technique. In this study, hardness and fatigue tests were performed on Co-Cr-Mo alloy components manufactured by SLM, and microstructure images were acquired and evaluated. When the microstructure of the samples was analyzed, tiny precipitates localized at the grain boundaries were discovered, along with the dominating γ phase. The average hardness value of the samples subjected to the Vickers microhardness test was 482±10. The fatigue life of the samples at the maximum stress of 800 MPa was 47,351 cycles. At the minimum stress of 400 MPa, the fatigue life exceeded 107 cycles. When fatigue fracture surfaces were examined, flat fracture surfaces similar to semi-cleavage were detected. The results will contribute to the literature on the mechanical characterization of SLM manufactured Co-Cr-Mo alloy components.



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