Journal of Zhejiang University

Journal of Zhejiang University SCIENCE A

Accepted manuscript available online (unedited version)

Synergistic enhancement of machinability and surface integrity in bulk metallic glasses via cold plasma pretreatment and ultrasonic vibration-assisted micromilling

Author(s): Qilin LI, Emek Babuskin KOCYIGIT, Long YE, Nan YU, Pingfa FENG, Jianjian WANG
Affiliation(s): State Key Laboratory of Tribology in Advanced Equipment, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China; more
Corresponding email(s): wangjjthu@tsinghua.edu.cn
Key Words: Bulk metallic glass (BMG); Micromilling; Cold plasma (CP); Ultrasonic vibration; Surface integrity

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Qilin LI, Emek Babuskin KOCYIGIT, Long YE, Nan YU, Pingfa FENG, Jianjian WANG. Synergistic enhancement of machinability and surface integrity in bulk metallic glasses via cold plasma pretreatment and ultrasonic vibration-assisted micromilling[J]. Journal of Zhejiang University Science A,in press.Frontiers of Information Technology & Electronic Engineering,in press.https://doi.org/10.1631/jzus.A2500552

@article{title="Synergistic enhancement of machinability and surface integrity in bulk metallic glasses via cold plasma pretreatment and ultrasonic vibration-assisted micromilling",
author="Qilin LI, Emek Babuskin KOCYIGIT, Long YE, Nan YU, Pingfa FENG, Jianjian WANG",
journal="Journal of Zhejiang University Science A",
year="in press",
publisher="Zhejiang University Press & Springer",
doi="https://doi.org/10.1631/jzus.A2500552"
}

%0 Journal Article
%T Synergistic enhancement of machinability and surface integrity in bulk metallic glasses via cold plasma pretreatment and ultrasonic vibration-assisted micromilling
%A Qilin LI
%A Emek Babuskin KOCYIGIT
%A Long YE
%A Nan YU
%A Pingfa FENG
%A Jianjian WANG
%J Journal of Zhejiang University SCIENCE A
%P 466-478
%@ 1673-565X
%D in press
%I Zhejiang University Press & Springer
doi="https://doi.org/10.1631/jzus.A2500552"

TY - JOUR
T1 - Synergistic enhancement of machinability and surface integrity in bulk metallic glasses via cold plasma pretreatment and ultrasonic vibration-assisted micromilling
A1 - Qilin LI
A1 - Emek Babuskin KOCYIGIT
A1 - Long YE
A1 - Nan YU
A1 - Pingfa FENG
A1 - Jianjian WANG
J0 - Journal of Zhejiang University Science A
SP - 466
EP - 478
%@ 1673-565X
Y1 - in press
PB - Zhejiang University Press & Springer
ER -
doi="https://doi.org/10.1631/jzus.A2500552"

Abstract
Chinese Summary
Academic Network
Reviewer Comment

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

作者：李麒麟^1,2，Emek Babuskin KOCYIGIT^1,2，叶龙³，于楠³，冯平法^1,2，王健健^1,2
机构：¹清华大学，机械工程系，先进装备摩擦学国家重点实验室，中国北京，100084；²清华大学，机械工程系，北京精密/超精密制造装备与控制重点实验室，中国北京，100084；³爱丁堡大学，工程学院材料与过程研究所，英国苏格兰爱丁堡，EH9 3FB
目的：块状金属玻璃具有优异的力学性能，但因其高硬度和高脆性导致可加工性差，所以传统微铣削易造成刀具快速磨损和表面缺陷。本文旨在探究冷等离子体预处理与超声振动辅助微铣削的协同作用，开发一种新型复合加工策略，以提升金属玻璃的微铣削质量与效率。
创新点：1.提出并研究了金属玻璃低温等离子体预处理与超声振动辅助微铣削相结合的加工方法；2.明确了低温等离子体预处理与超声振动辅助微铣削的协同效应，并且在实现切削力降低的同时，有效抑制了刀具磨损。
方法：1.通过接触角测量、纳米压痕与纳米划痕实验，量化等离子体处理对金属玻璃表面润湿性、弹性模量与塑性变形行为的影响；2.采用四种工艺方法（传统铣削、低温等离子体辅助铣削、超声振动辅助铣削及两者结合的方法）进行微铣削对比试验；3.使用测力仪测量切削力，使用激光共聚焦显微镜分析表面粗糙度，使用超景深显微镜观察刀具磨损与刃口崩缺，并系统评价各方法的加工性能。
结论：1.低温等离子体预处理能显著地提升金属玻璃的可加工性，进而实现最佳表面质量与最小刀具磨损；2.超声振动辅助铣削虽可降低平均切削力，但会引发严重的刀具刃口崩缺，导致加工过程不稳定与表面质量下降；3.所提出的低温等离子体预处理与超声振动辅助微铣削复合工艺发挥了协同优势：在保留超声振动降低切削力效果的同时，大幅减轻了超声振动引起的刀具损伤，获得了更稳定、一致的表面质量。

关键词组：金属玻璃；微铣削；低温等离子体；超声振动

Darkslateblue:Affiliate; Royal Blue:Author; Turquoise:Article

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