Authors:
Chaofan Shi
;
Suiyuan Chen
;
Qing Xia
and
Zhuang Li
Affiliation:
Key Laboratory for Anisotropy and Texture of Materials, Ministry of Education, Key Laboratory for Laser Application Technology of Liaoning Province. School of Materials and Engineering and Northeastern University, China
Keyword(s):
Selective laser melting, Brake disc, 24CrNiMoY steel, Microstructure, Hardness.
Abstract:
In this paper, 1.5% ZrO2 was added in 24CrNiMoY alloy steel powder to form a composite powder, and the alloy steel sample was prepared by selective laser melting technology. Effects of different laser power and scanning speed on the microstructure and hardness of the fabricated sample were studied by OM, XRD, SEM and hardness test. The results show that when the optimized laser power is 1700 W and scanning speed is 10mm/s, the phase structure is composed of martensite, bainite, ferrite and carbide. The microstructure is uniform and fine, there are no cracks in the fabricated sample, the porosity is 0.96%. The average hardness is 467 HV, ZrO2 plays a role on improving the hardness. The alloy steel sample prepared by SLM has a fine microstructure and high hardness, which provides a basis for laser additive manufacturing of high-speed brake disc.