Please use this identifier to cite or link to this item: https://hdl.handle.net/10356/103419
Title: Comparative study of laser surface hardening of 50CrMo4 steel using continuous-wave laser and pulsed lasers with ms, ns, ps and fs pulse duration
Authors: Maharjan, Niroj
Zhou, Wei
Zhou, Yu
Guan, Yingchun
Wu, Naien
Keywords: Laser Hardening
Pulsed Laser
DRNTU::Engineering::Manufacturing
Issue Date: 2019
Source: Maharjan, N., Zhou, W., Zhou, Y., Guan, Y., & Wu, N. (2019). Comparative study of laser surface hardening of 50CrMo4 steel using continuous-wave laser and pulsed lasers with ms, ns, ps and fs pulse duration. Surface and Coatings Technology, 366311-320. doi:10.1016/j.surfcoat.2019.03.036
Series/Report no.: Surface and Coatings Technology
Abstract: Laser surface hardening, used to achieve hardened surface without affecting bulk properties of steels, generally employs continuous-wave laser to do the job. The purpose of this paper is to systematically investigate the use of different pulsed lasers for surface hardening of 50CrMo4 steel. A continuous-wave laser and various pulsed lasers with pulse duration ranging from fs to ms were used for the experiment. It was found that millisecond laser utilizing about 9 times lower power is as effective as continuous-wave laser for surface hardening. It produced an average surface hardness of ~719 HV (2.7 times higher than base material hardness) and ~200 µm hardened depth, which is comparable with continuous-wave laser hardening. Similarly, nanosecond laser could induce both surface hardening effect and material removal depending on the parameters used. However, a shallow hardened depth (of mere ~80 µm) was achieved compared to continuous-wave laser. Furthermore, femtosecond and picosecond lasers did not produce any observable surface hardening effect; instead they resulted in direct surface ablation.
URI: https://hdl.handle.net/10356/103419
http://hdl.handle.net/10220/48253
ISSN: 0257-8972
DOI: http://dx.doi.org/10.1016/j.surfcoat.2019.03.036
Rights: © 2019 Elsevier. All rights reserved. This paper was published in Surface & Coatings Technology and is made available with permission of Elsevier.
Fulltext Permission: open
Fulltext Availability: With Fulltext
Appears in Collections:MAE Journal Articles

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