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产量的能力，而延展性是其永久性变形而无需断裂的能力。许多重要的工程应用需要高强度和延性材料，例如切割工具，士兵的防弹衣和制造过程。一个有前途的候选人是碳化物碳化物，这是一个所谓的超级陶瓷名称，因此其力量。但是，它的延展性较低。在多结晶材料中，强度和延展性通常与较低长度尺度（微米及以下）处的微结构特征有关。关于微观结构对超硬陶瓷的强度和延展性的影响，存在很大的知识差距。该项目针对研究微观结构之间关系的物理机制，并使用计算建模和仿真之间的基于硼碳化物材料的强度和延展性。该项目还将根据获得增强强度和延展性的新型碳化物材料的知识来建立设计原理。设计策略将扩展到各种其他超级材料，例如硼化物，碳化物和钻石。该研究将纳入本科和研究生教育，以及当地高中生的外展活动。该研究项目还将针对妇女和代表性不足的少数民族学生参与科学，技术，工程和数学学科。 该项目的研究目标是说明微观结构如何确定基于硼碳化物的材料的变形和机械过程。研究小组将应用多尺度方法耦合原子建模和中尺度相位场方法来（1）研究晶界对硼碳化物机械性能，变形和故障机制的影响； （2）建立设计原理，以通过微合同的晶界特性工程来增强碳化物碳化物的强度和延展性。这项研究将在阐明在现实条件下阐明多晶超陶瓷的强度和延展性的起源。材料设计原理将用于激发实验性综合用于商业应用的较强，更坚固的碳化物材料。

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

Mitigating the formation of amorphous shear band in boron carbide

• DOI: 10.1063/5.0044526
• 发表时间: 2021-04
• 期刊: Journal of Applied Physics
• 影响因子: 3.2
• 作者: Yidi Shen;Jon Fuller;Q. An