Review on mechanism and process of surface polishing using lasers

Arun KRISHNAN, Fengzhou FANG

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PDF(1938 KB)
Front. Mech. Eng. ›› 2019, Vol. 14 ›› Issue (3) : 299-319. DOI: 10.1007/s11465-019-0535-0
REVIEW ARTICLE

Review on mechanism and process of surface polishing using lasers

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Abstract

Laser polishing is a technology of smoothening the surface of various materials with highly intense laser beams. When these beams impact on the material surface to be polished, the surface starts to be melted due to the high temperature. The melted material is then relocated from the ‘peaks to valleys’ under the multidirectional action of surface tension. By varying the process parameters such as beam intensity, energy density, spot diameter, and feed rate, different rates of surface roughness can be achieved. High precision polishing of surfaces can be done using laser process. Currently, laser polishing has extended its applications from photonics to molds as well as bio-medical sectors. Conventional polishing techniques have many drawbacks such as less capability of polishing freeform surfaces, environmental pollution, long processing time, and health hazards for the operators. Laser polishing on the other hand eliminates all the mentioned drawbacks and comes as a promising technology that can be relied for smoothening of initial topography of the surfaces irrespective of the complexity of the surface. Majority of the researchers performed laser polishing on materials such as steel, titanium, and its alloys because of its low cost and reliability. This article gives a detailed overview of the laser polishing mechanism by explaining various process parameters briefly to get a better understanding about the entire polishing process. The advantages and applications are also explained clearly to have a good knowledge about the importance of laser polishing in the future.

Keywords

laser polishing / surface roughness / process parameters / mechanism

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Arun KRISHNAN, Fengzhou FANG. Review on mechanism and process of surface polishing using lasers. Front. Mech. Eng., 2019, 14(3): 299‒319 https://doi.org/10.1007/s11465-019-0535-0

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Acknowledgements

The authors would like to thank Fusheng Liang for his support in referencing. Thanks also to the support received from the Science Foundation Ireland (SFI) (Grant No. 15/RP/B3208) and the National Natural Science Foundation of China (NSFC) (Grant Nos. 51320105009 and 61635008).Open AccessƒThis article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made.ƒThe images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder.ƒTo view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.

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