Microstructure, Mechanical Properties, and Corrosion Behavior of 06Cr15Ni4CuMo Processed by Using Selective Laser Melting

Abstract

A new class of martensitic stainless steel, namely 06Cr15Ni4CuMo, with applications in marine engineering, was processed by using selective laser melting (SLM). A body-centered cubic martensitic microstructure was observed, and the microstructure was compared with wrought 410 martensitic stainless steel. The SLM-processed sample showed a hardness of 465 ± 10 HV0.5, which was nearly 115 HV0.5 less than the wrought counterpart. Similarly, the SLM-processed sample showed improved YS and UTS, compared with the wrought sample. However, reduced ductility was observed in the SLM-processed sample due to the presence of high dislocation density in these samples. In addition, 71% volume high-angle grain boundaries were observed, corroborating the high strength of the material. The corrosion behavior was investigated in seawater, and the corrosion resistance was found to be 0.025 mmpy for the SLM-processed 06Cr15Ni4CuMo steel and 0.030 mmpy for wrought 410 alloys, showing better corrosion resistance in the SLM-processed material.

Novel Assessment Methodology for Laser Metal Deposition of New Metallic Alloys

“…However, most of the metallic alloys used nowadays were developed for conventional manufacturing processes, with different melting and solidification properties from the AM technologies [ 3 ]. Laser-based metallic AM processes are characterized by complex thermal histories that involve directional heat extraction, high thermal gradients, and rapid solidification, with cooling rates on the order of 10 5 –10 6 K/s [ 12 ]. In addition, the repeated melting and tempering cycles of the layer-by-layer AM manufacturing produce microstructures and properties different from those obtained in conventional processes [ 13 ].…”