Porosity, residual stress, wear properties and impact toughness of additively manufactured low-alloy steel: A review

As additive manufacturing (AM) is increasingly being employed to manufacture functional parts, a growing number of metal powders are being studied to match the needs of the applications. Most of the available metal powders for powder-based additive manufacturing are costly, which restricts their widespread use. Low-alloy steel is an affordable option for the manufacturing of functional parts via AM for the automotive, aerospace, and structural sectors. The properties of low-alloy steels, such as wear and impact toughness, are significantly influenced by the porosity and residual stress resulting from the process parameters of the AM techniques. Although low-alloy steels have huge potential for the fabrication of structural components via AM, no study has reviewed the properties of additively manufactured low-alloy steels. In this article, the effect of different process parameters and post-printing heat treatments on porosity, residual stress, wear, and impact toughness of different low-alloy steels (4130, 4140, 4340, 5115, 5120, 8620, 8740, 24CrNiMo, Bainidur, 12CrNi2, 30CrNiMo8, E185 AMPO, 30CrMnSiA, Q345B, 300 M, HSLA100, DP600) have been reviewed.