High-speed manufacturing-driven strength-ductility improvement of H13 tool steel fabricated by selective laser melting

ABSTRACT

H13 tool steel was additively manufactured by selective laser melting (SLM). The sample printed at a higher laser scan speed exhibited higher strength and ductility than those of the sample printed at a lower speed. The samples were repeatedly exposed to a massive heat input during the SLM. The in-situ tempering effect was applied to the sample; the phase fraction is changed by varying the heat input by controlling the laser scan speed. The microstructure analysis showed that the sample printed at a higher scan speed had a higher fraction of retained austenite than at a lower speed. The former was affected by deformation-induced martensitic transformation with enhanced strain-hardening ability. This study entailed the control of process parameters to improve the mechanical properties and the productivity of SLM-printed H13 tool steel. It investigated the relationship between the laser scan speed and the phase fraction, whose effect on the mechanical properties was confirmed.

KEYWORDS:

• H13 tool steel
• additive manufacturing
• microstructure
• mechanical property
• phase transformation

Disclosure statement

No potential conflict of interest was reported by the author(s).

Correction Statement

This article has been corrected with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

This work was supported by Principal R&D Project (PNK8290) of the Korean Institute of Materials Science (KIMS), and Basic Research Program (PICO190) of Korea Institute of Machinery and Materials (KIMM).