Direct Metal Tool Fabrication of AISI 420 Tool Steel by Selective Laser Melting

Abstract

Recently, the improvement of Additive Manufacturing systems and processes promise the fabrication of nearly full density metal tools and moulds for long-term use. However, only a few kinds of tool steel were processed by SLM successfully. The AISI 420 tool steel is introduced as the processing material for its good corrosion resistance and excellent polishability as the injection mould. The scanning speed and laser power were optimized to fabricate the samples. The maximum density achieved with AISI 420 tool steel was about 99.955%, and defects of small pores were found. The samples had a maximum hardness of HRC 50.74, showing a great potential to fabricate the real injection mould.