Abstract: Bulk metallic glasses (BMGs) exhibit exceptional properties, but are difficult to machine due to their high hardness and brittleness. In this study, we propose a novel hybrid machining strategy integrating cold plasma (CP) pretreatment with ultrasonic vibration-assisted micromilling (UVAM), termed CP-UVAM, to overcome these challenges. We reveal the fundamental mechanism by which CP independently optimizes machining: it transforms the BMG surface from hydrophobic to superhydrophilic (contact angle10°) through oxidation and the introduction of polar groups, thereby enhancing lubricant penetration. Crucially, CP treatment increases the near-surface free volume, significantly improving plastic deformability, as evidenced by nanoindentation (15%‒20% reduction in the first pop-in force) and nanoscratching tests. Four methods—conventional milling (CM), CP-assisted milling (CPAM), UVAM, and CP-UVAM—were systematically compared. While CPAM alone delivered the best surface finish and least tool wear, UVAM achieved a 29.02% cutting force reduction at the cost of severe tool edge chipping. The synergistic CP-UVAM approach retained the force reduction advantage of UVAM (34.36% reduction vs CM) while dramatically mitigating UVAM-induced tool damage, reducing edge chipping by 43.97%, and achieving superior surface consistency (a surface roughness of 2.601 µm in the stable state). This study demonstrates that CP independently enhances BMG machinability and works synergistically with UVAM, enabling high-precision micromilling of this challenging material through the combination of plasma-induced plasticity and wettability with ultrasonic vibration-assisted force reduction.

低温等离子体与超声振动协同增效的金属玻璃微铣削研究

[1]BakkalM, LiuCT, WatkinsTR, et al., 2004. Oxidation and crystallization of Zr-based bulk metallic glass due to machining. Intermetallics, 12(2):195-204.

[2]ChenZM, FengPF, WangJJ, et al., 2022. Understanding the abnormal effects of ultrasonic vibration on tool wear and surface generation in Zr-based bulk metallic glass cutting. CIRP Journal of Manufacturing Science and Technology, 39:1-17.

[3]GaoGF, SunZ, PanXR, et al., 2024. Study of longitudinal-torsional ultrasonic-assisted vibration on micro-hole drilling Zr-based metallic glass. The International Journal of Advanced Manufacturing Technology, 131(5):2893-2907.

[4]LiH, YangJ, ZhangC, et al., 2025. Different non-traditional energy fields assisted milling of SiCf/SiC composites: investigation on tool wear mechanisms and effects on machined surface quality. Wear, 571:205844.

[5]LiuJY, SongJL, ChenY, et al., 2021. Atmospheric pressure cold plasma jet–assisted micro-milling TC4 titanium alloy. The International Journal of Advanced Manufacturing Technology, 112(7):2201-2209.

[6]LiuX, WangBQ, LiYH, et al., 2023. Improving machinability of single-crystal silicon by cold plasma jet. Journal of Manufacturing Processes, 99:581-591.

[7]LvJW, WeiC, ShiZL, et al., 2022. The size-dependence of compressive mechanical properties and serrated-flow behavior of Ti-based bulk metallic glass. Materials Science and Engineering: A, 857:143968.

[8]MustafaG, LiuJY, ZhangF, et al., 2019. Atmospheric pressure plasma jet assisted micro-milling of Inconel 718. The International Journal of Advanced Manufacturing Technology, 103(9):4681-4687.

[9]PuthucodeA, BanerjeeR, VadlakondaS, et al., 2008. Incipient plasticity and shear band formation in bulk metallic glass studied using indentation. Metallurgical and Materials Transactions A, 39(7):1552-1559.

[10]RayD, PuriAB, Nagahanumaiah, 2019. Investigation on cutting forces and surface finish in mechanical micro milling of Zr-based bulk metallic glass. Journal of Advanced Manufacturing Systems, 18(1):113-132.

[11]SchuhCA, NiehTG, 2003. A nanoindentation study of serrated flow in bulk metallic glasses. Acta Materialia, 51(1):87-99.

[12]ShanS, FengPF, ZhaH, et al., 2020. Building of longitudinal ultrasonic assisted turning system and its cutting simulation study on bulk metallic glass. Materials, 13(14):3131.

[13]WangT, WuXY, ZhangGQ, et al., 2020a. Experimental study on machinability of Zr-based bulk metallic glass during micro milling. Micromachines, 11(1):86.

[14]WangT, WuXY, ZhangGQ, et al., 2020b. Study on surface roughness and top burr of micro-milled Zr-based bulk metallic glass in shear dominant zone. The International Journal of Advanced Manufacturing Technology, 107(9):4287-4299.

[15]WangZH, LiYH, WangSS, et al., 2024. Feasibility and mechanism of atmospheric pressure cold plasma jet (APCPJ) assisted micro-milling of bulk metallic glasses (BMGs). Ceramics International, 50(7):11094-11105.

[16]XieBY, KumarMN, YanDP, et al., 2017. Material behavior in micro milling of zirconium based bulk metallic glass. TMS 2017 146th Annual Meeting Exhibition Supplemental Proceedings, p.363-373.

[17]YamamuraK, TakiguchiT, UedaM, et al., 2010. High-integrity finishing of 4H-SiC (0001) by plasma-assisted polishing. Advanced Materials Research, 126-128:423-428.

[18]ZhangL, HuangH, 2019. Micro machining of bulk metallic glasses: a review. The International Journal of Advanced Manufacturing Technology, 100(1):637-661.

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