Comparative study of laser surface hardening of 50CrMo4 steel using continuous-wave laser and pulsed lasers with ms, ns, ps and fs pulse duration
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 contin...
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sg-ntu-dr.10356-1034192023-03-04T17:11:25Z Comparative study of laser surface hardening of 50CrMo4 steel using continuous-wave laser and pulsed lasers with ms, ns, ps and fs pulse duration Maharjan, Niroj Zhou, Wei Zhou, Yu Guan, Yingchun Wu, Naien School of Mechanical and Aerospace Engineering Advanced Remanufacturing and Technology Centre Laser Hardening Pulsed Laser DRNTU::Engineering::Manufacturing 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. Accepted version 2019-05-17T05:06:32Z 2019-12-06T21:12:17Z 2019-05-17T05:06:32Z 2019-12-06T21:12:17Z 2019 Journal Article 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, 366, 311-320. doi:10.1016/j.surfcoat.2019.03.036 0257-8972 https://hdl.handle.net/10356/103419 http://hdl.handle.net/10220/48253 10.1016/j.surfcoat.2019.03.036 366 311 320 en Surface and Coatings Technology © 2019 Elsevier. All rights reserved. This paper was published in Surface & Coatings Technology and is made available with permission of Elsevier. 27 p. application/pdf |
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Laser Hardening Pulsed Laser DRNTU::Engineering::Manufacturing Maharjan, Niroj Zhou, Wei Zhou, Yu Guan, Yingchun Wu, Naien Comparative study of laser surface hardening of 50CrMo4 steel using continuous-wave laser and pulsed lasers with ms, ns, ps and fs pulse duration |
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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. |
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School of Mechanical and Aerospace Engineering |
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School of Mechanical and Aerospace Engineering Maharjan, Niroj Zhou, Wei Zhou, Yu Guan, Yingchun Wu, Naien |
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Article |
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Maharjan, Niroj Zhou, Wei Zhou, Yu Guan, Yingchun Wu, Naien |
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Maharjan, Niroj |
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 |
title_short |
Comparative study of laser surface hardening of 50CrMo4 steel using continuous-wave laser and pulsed lasers with ms, ns, ps and fs pulse duration |
title_full |
Comparative study of laser surface hardening of 50CrMo4 steel using continuous-wave laser and pulsed lasers with ms, ns, ps and fs pulse duration |
title_fullStr |
Comparative study of laser surface hardening of 50CrMo4 steel using continuous-wave laser and pulsed lasers with ms, ns, ps and fs pulse duration |
title_full_unstemmed |
Comparative study of laser surface hardening of 50CrMo4 steel using continuous-wave laser and pulsed lasers with ms, ns, ps and fs pulse duration |
title_sort |
comparative study of laser surface hardening of 50crmo4 steel using continuous-wave laser and pulsed lasers with ms, ns, ps and fs pulse duration |
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2019 |
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https://hdl.handle.net/10356/103419 http://hdl.handle.net/10220/48253 |
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1759855044113465344 |