Numerical simulation of multi-principal elements high-entropy alloy milling based on minimal quantity lubrication
ObjectivesHigh-entropy alloys (HEA) with multi-principal elements have many excellent characteristics such as high strength, high hardness and high wear resistance, which have attracted widespread attention from scholars. However, the mechanical processing of HEA is difficult. This study utilizes mi...
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| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | zho |
| Published: |
Zhengzhou Research Institute for Abrasives & Grinding Co., Ltd.
2025-06-01
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| Series: | Jin'gangshi yu moliao moju gongcheng |
| Subjects: | |
| Online Access: | http://www.jgszz.cn/article/doi/10.13394/j.cnki.jgszz.2023.0265 |
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| Summary: | ObjectivesHigh-entropy alloys (HEA) with multi-principal elements have many excellent characteristics such as high strength, high hardness and high wear resistance, which have attracted widespread attention from scholars. However, the mechanical processing of HEA is difficult. This study utilizes minimal quantity lubrication (MQL) technology for milling HEA to improve their machining performance and explore the influences of different milling parameters on their milling force. MethodsThe thermodynamic coupling milling model of HEA (CoCrFeNiMn) and a four-edge end milling cutter is established using finite element simulation software. The difference in milling force between MQL milling and dry milling is studied by analyzing the material removal mechanism, and the influences of different milling parameters on milling forces are studied by single-factor experiments. Firstly, the three-dimensional model of the four-edge end milling cutter, the J-C constitutive model of HEA (CoCrFeNiMn), the heat conduction model and the contact friction model are established, and the material failure separation criteria are determined and the milling model is established. Then, the material removal mechanism under the thermodynamic coupling condition is analyzed, and the changes in milling forces between MQL milling and dry milling are analyzed from the perspectives of equivalent stress, contact friction and the thermal softening effect, and the advantages of MQL technology for milling HEA (CoCrFeNiMn) are analyzed. Finally, the effects of feed speed, spindle speed and milling depth on milling force are obtained by single-factor tests.ResultsThrough comparative experiments between dry milling and MQL milling, it is found that：(1) The equivalent stress produced by the two milling methods are concentrated in the first deformation zone, and the equivalent stress of dry milling is also concentrated in the position near the cutting edge. (2) The equivalent stress value of MQL milling in the first deformation zone is slightly greater than that of dry milling. (3) The heat generated by the two milling methods is concentrated in the first deformation zone and the chips, and the chips take away most of the heat. The chip temperature generated by dry milling is significantly higher than that generated by MQL milling. (4) MQL milling significantly reduces the temperature at the cutting site and improves chip integrity. (5) When the milling depth is 0.15 to 0.20 mm, the milling force of MQL milling is basically the same as that of dry milling. When the milling depth is greater than 0.20 mm, the ability of MQL milling to reduce milling force increases with the increase of milling depth. This is due to the use of MQL technology in the milling process, which compensates for the reduced milling force caused by low friction coefficient and the increased milling force caused by weak thermal softening effect. The MQL milling single-factor tests show that: (1) The milling force increases with the increase of feed speed, and decreases with the increase of spindle speed, that is, it increases with the increase of feed rate per tooth. (2) The milling force increases with the increase of milling depths, and the effect of feed rate per tooth on the average milling force is gradually intensified with the increase of milling depth. ConclusionsThe MQL milling has obvious advantages, which can significantly reduce milling force at milling depth greater than 0.20 mm, and the ability to reduce milling force increases with the increase of milling depth. In addition, the use of MQL technology in the milling process can significantly reduce the temperature at the cutting position, improve HEA machining accuracy, and avoid a series of defects of traditional pouring lubrication. The cutting force in MQL milling conforms to the change law of cutting force in most metal milling with the process parameters. In MQL milling, the milling force can be further reduced by increasing the spindle speed and reducing the feed speed. When the milling depth is large, the spindle speed should be further increased and the feed speed should be reduced to reduce the feed per tooth, in order to deal with the high sensitivity of the milling force to the milling depth. |
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| ISSN: | 1006-852X |