Modeling and Design of Enhanced Strength and Ductility Through Grain Boundary Engineering--A Study of Boron Carbide Based Superhard Materials

通过晶界工程增强强度和延展性的建模与设计--碳化硼基超硬材料的研究

• 批准号: 1727428
• 负责人: Qi An
• 金额: $ 47.64万
• 依托单位: Board of Regents, NSHE, obo University of Nevada, Reno
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-08-01 至 2022-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1727428&HistoricalAwards=false
• 关键词: Modeling; Design; Enhanced; Strength; Ductility

Strength refers to a material's ability to withstand failure or yield, while ductility is its ability to permanently deform without fracture. Many important engineering applications require high strength and yet ductile materials, such as in cutting tools, body armor for soldiers, and manufacturing process. One promising candidate is boron carbide, a so-called superhard ceramic names so because of its strength; however, it has low ductility. In poly-crystalline materials, the strength and ductility are commonly associated with microstructural features at the lower length scales (micrometers and below). There is a significant knowledge gap regarding the impact of microstructure on the strength and ductility of superhard ceramics. This project is directed towards the study of the physical mechanisms that underlie the relationships between microstructure, and strength and ductility of boron carbide based materials using computational modeling and simulations. The project will also establish design principles based on the knowledge gained for the development of new boron carbide based materials with enhanced strength and ductility. The design strategies will be extendable to a variety of other superhard materials, such as borides, carbides, and diamond. The research will be integrated into both undergraduate and graduate education, as well as outreach activities for local high school students. The research project will also target the participation of women and under-represented minority students in science, technology, engineering, and math disciplines. The research objective of this project is to illustrate how microstructure determines the deformation and mechanical processes in boron carbide based materials. The research team will apply a multiscale approach coupling atomistic modeling and the mesoscale phase field method to (1) investigate the impact of grain boundaries on mechanical properties, deformation, and failure mechanisms of boron carbide; and (2) establish the design principles to enhance the strength and ductility of boron carbide through engineering of grain boundary properties with microalloying. The research will make original contributions in elucidating the origins of the strength and ductility of polycrystalline superhard ceramics under realistic conditions. The materials design principles will be applied to inspire experimental synthesis of stronger and tougher boron carbide based materials for commercial applications.

强度是指材料承受失败或屈服的能力，而延展性是指其永久变形而不断裂的能力。许多重要的工程应用需要高强度和延展性的材料，例如在切割工具、士兵防弹衣和制造过程中。一个很有希望的候选者是碳化硼，一种所谓的超硬陶瓷，因为它的强度而得名；然而，它的延展性很低。在多晶材料中，强度和延展性通常与较低长度尺度(微米及以下)的微观结构特征有关。关于显微结构对超硬陶瓷的强度和延展性的影响，人们的认识差距很大。本项目旨在通过计算建模和模拟来研究碳化硼基材料微观结构与强度和塑性之间关系的物理机制。该项目还将建立基于所获得的知识的设计原则，以开发具有更高强度和延展性的新型碳化硼材料。设计策略将扩展到各种其他超硬材料，如硼化物、碳化物和钻石。这项研究将纳入本科生和研究生教育，以及针对当地高中生的外联活动。该研究项目还将针对女性和未被充分代表的少数民族学生参与科学、技术、工程和数学学科。本项目的研究目的是阐明显微组织如何决定碳化硼材料的变形和力学过程。研究小组将应用原子模拟和介观相场方法相结合的多尺度方法来(1)研究晶界对碳化硼的力学性能、变形和失效机制的影响；以及(2)建立通过微合金化的晶界性能工程来提高碳化硼的强度和塑性的设计原则。这项研究将为阐明多晶超硬陶瓷在现实条件下的强度和塑性的来源做出创新性的贡献。材料设计原则将被应用于启发更强、更韧的碳化硼基材料的实验合成，用于商业应用。

项目成果

Enhanced fracture toughness of boron carbide from microalloying and nanotwinning

• DOI: 10.1016/j.scriptamat.2018.11.035
• 发表时间: 2019-03
• 期刊: Scripta Materialia
• 影响因子: 6
• 作者: Yidi Shen;Guodong Li;Q. An

Photomechanical effect leading to extraordinary ductility in covalent semiconductors

• DOI: 10.1103/physrevb.100.094110
• 发表时间: 2019-09
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: Hongwei Wang;Shuangxi Song;Xinshu Zou;Fangxi Wang;Zhifu Zhang;S. Morozov;Xiaodong Wang;K. Reddy;Q. An

Electron–Hole Excitation Induced Softening in Boron Carbide-Based Superhard Materials

碳化硼基超硬材料中电子空穴激发引起的软化

• DOI: 10.1021/acsami.2c05528
• 发表时间: 2022
• 期刊: ACS Applied Materials & Interfaces
• 影响因子: 9.5
• 作者: He, Yi;Shen, Yidi;Tang, Bin;An, Qi
• 通讯作者: An, Qi

Grain Boundary Sliding and Amorphization are Responsible for the Reverse Hall-Petch Relation in Superhard Nanocrystalline Boron Carbide

• DOI: 10.1103/physrevlett.121.145504
• 发表时间: 2018-10-04
• 期刊: PHYSICAL REVIEW LETTERS
• 影响因子: 8.6
• 作者: Guo, Dezhou;Song, Shuangxi;An, Qi
• 通讯作者: An, Qi

Graphite interface mediated grain-boundary sliding leads to enhanced mechanical properties of nanocrystalline silicon carbide

• DOI: 10.1016/j.mtla.2019.100394
• 发表时间: 2019-07
• 期刊: Materialia
• 影响因子: 3.4
• 作者: K. Madhav Reddy;Dezhou Guo;Simanta Lahkar;Chun-Yang Cheng;Y. Shinoda;Q. An;Xiaodong Wang