CAREER: Material Removal Mechanism of Ceramic Materials in Ultra-Precision Machining

职业：超精密加工中陶瓷材料的材料去除机制

• 批准号: 1844821
• 负责人: Sangkee Min
• 金额: $ 50万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-02-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1844821&HistoricalAwards=false
• 关键词: CAREER; Material; Removal; Mechanism; Ceramic

This Faculty Early Career Development (CAREER) Program research will create a fundamental understanding of ceramic material removal during nanoscale machining. Ceramics, such as sapphire, zirconia, calcium fluoride, etc., have many superior mechanical, chemical, biomedical and optical properties, but fabricating ceramic components is very difficult due to their high hardness and brittleness. However, at a microscopic scale, ceramics can be machined like metals, although the mechanism explaining this phenomenon is not yet known. General machining creates cracks on ceramic surfaces because the crystal structure of the material is prone to fracture. Each crystal structure has multiple fracture systems; each fracture system can be initiated under some conditions, especially high pressure. This study will explore how the force generated by cutting action initiates fracture and will use this understanding so that cutting can be done without generating cracks. The research will allow the use of ceramics in various industries, including consumer electronics, biomedical and defense applications, and optical elements. Thus, the research directly and favorably affects economic welfare and national security. The knowledge generated from this project will be distributed through the advanced CNC (Computer Numerical Control) machine training program, online expert system, and public media in addition to journal publication and integration into undergraduate and graduate courses. The project goal is to understand how the microscopic crystal structure of ceramics influences material behavior during machining. The research will identify the activation mechanisms of ductile shear and brittle fracture of ceramics. This knowledge will lead to the development of machining strategies to suppress brittle fracture and to enable ductile mode machining on ceramics for a wide range of applications. The research will initially test the role of three potential parameters (resolved shear stress, fracture energy, and stress intensity factor) in activating plastic deformation or crack initiation. Specific contributions will include: (1) data generation on critical depth of cut where ductile to brittle transition occurs for all orientations for each distinctive crystal plane of sapphire and zirconia; (2) identification of triggering parameter(s) on activation of slip system or fracture system; and (3) modeling of ceramic machining.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

这项教师早期职业发展（职业）计划研究将对纳米级加工期间的陶瓷物质去除产生基本的理解。陶瓷，例如蓝宝石，锆，氟化钙等，具有许多优质的机械，化学，生物医学和光学特性，但是由于它们的高硬度和脆性，制造陶瓷成分非常困难。然而，在微观规模上，陶瓷可以像金属一样加工，尽管解释这种现象的机制尚不清楚。一般加工会在陶瓷表面上产生裂缝，因为材料的晶体结构容易裂缝。每个晶体结构都有多个断裂系统。每个断裂系统都可以在某些条件下启动，尤其是高压。这项研究将探讨如何通过切割动作产生的力引发断裂，并使用此理解，以便在不产生裂缝的情况下进行切割。该研究将允许在各种行业中使用陶瓷，包括消费电子，生物医学和国防应用以及光学元素。因此，该研究直接而有利地影响了经济福利和国家安全。该项目产生的知识将通过高级CNC（计算机数值控制）机器培训计划，在线专家系统和公共媒体进行分发，此外还有期刊出版和集成到本科和研究生课程中。 项目目标是了解陶瓷的显微镜晶体结构如何影响加工过程中的材料行为。该研究将确定脱氧剪切和易碎陶瓷断裂的激活机制。这些知识将导致制定加工策略，以抑制脆性断裂并在陶瓷上实现广泛应用的陶瓷加工。该研究最初将测试三个潜在参数（分辨剪切应力，断裂能和应力强度因子）在激活塑性变形或裂纹开始中的作用。具体的贡献将包括：（1）在临界深度上的数据生成，其中对于蓝宝石和氧化锆的每个独特的晶体平面的所有方向都会发生延性到脆性过渡； （2）识别触发参数在激活滑移系统或断裂系统的激活中； （3）陶瓷加工的建模。该奖项反映了NSF的法定任务，并被认为是使用基金会的知识分子优点和更广泛的影响审查标准的评估值得支持的。

项目成果

Study of material removal behavior on R-plane of sapphire during ultra-precision machining based on modified slip-fracture model

• DOI: 10.1016/j.npe.2020.07.001
• 发表时间: 2020-09
• 期刊: Nanotechnology and Precision Engineering
• 作者: S. Kwon;A. Nagaraj;H. Yoon;S. Min

Effect of the initial-flaw on crack-propagation in two-step cutting of monocrystalline sapphire

• DOI: 10.1016/j.jmapro.2020.06.017
• 发表时间: 2020-08
• 期刊: Journal of Manufacturing Processes
• 影响因子: 6.2
• 作者: H. Yoon;S. Kwon;A. Nagaraj;S. Min

Studying Crack Generation Mechanism in Single-Crystal Sapphire During Ultra-precision Machining by MD Simulation-Based Slip/Fracture Activation Model

• DOI: 10.1007/s12541-023-00776-w
• 发表时间: 2023-03
• 期刊: International Journal of Precision Engineering and Manufacturing
• 影响因子: 1.9
• 作者: S. Kwon;A. Nagaraj;Dalei Xi;Yiyang Du;Dae Nyoung Kim;Woo Kyun Kim;S. Min

Prediction of crack initiation in single-crystal sapphire during ultra-precision machining using MD simulation-based slip/fracture activation model

• DOI: 10.1016/j.precisioneng.2023.12.007
• 发表时间: 2023-12
• 期刊: Precision Engineering
• 作者: S. Kwon;A. Nagaraj;Dae Nyoung Kim;Dalei Xi;Yiyang Du;Woo Kyun Kim;Sangkee Min

Effects of surface coating materials on cutting forces and ductile-to-brittle transition in orthogonal cutting of monocrystalline sapphire

• DOI: 10.1016/j.jmapro.2022.09.046
• 发表时间: 2022-10-15
• 期刊: JOURNAL OF MANUFACTURING PROCESSES
• 影响因子: 6.2
• 作者: Yoon, Hae-Sung;Kwon, Suk Bum;Min, Sangkee
• 通讯作者: Min, Sangkee