摘要
采用第一性原理计算和实验相结合的方法,研究了金刚石/铝复合材料的界面性质及界面反应.计算结果表明:金刚石(100)/铝(111)界面粘附功更大,相比金刚石(111)/铝(111)的界面粘附功4.14 J/m^(2)提高了41%.同时,金刚石(100)/铝(111)界面处形成Al-C键合的趋势更强.Al-C键的引入能够促进金刚石(100)/铝(111)界面处C-C键的形成,提高界面粘附功.利用真空气压浸渗法制备金刚石/铝复合材料,并对金刚石/铝复合材料的界面结构进行多尺度表征.在金刚石{100}面观察到界面产物Al_(4)C_(3),且界面脱粘多发生在金刚石{111}面,实验现象与计算结果相一致.湿热实验研究了界面反应对金刚石/铝复合材料的影响,进一步表明抑制Al_(4)C_(3)生成、改善界面选择性结合对于提高金刚石/铝复合材料性能及稳定性具有重要意义.本文的研究为第一性原理计算金刚石/金属的界面性质提供了新的思路,也对金刚石/金属复合材料的设计具有重要的指导意义.
First-principles calculation and experimental methods are used to study the interfacial properties and reaction of diamond/Al composites.Based on the first-principles method,the interfacial adhesion work(Wad),electronic structure and charge transfer of diamond/Al models are calculated systematically.The results show that the adhesion work of diamond(100)/Al(111)is 41%higher than that of diamond(111)/Al(111),therefore,the interface bonding of diamond(100)/Al(111)interface is stronger.According to the analysis of the electronic structure,there are more charges transferring at the diamond(100)/Al(111)interface,and the high charge density is distributed on the side of C atoms.The redistribution of charges at the interface is conducive to the formation of Al—C bond,so that the tendency of forming Al—C bonds is greater.The introduction of Al—C bond can promote the formation of C—C bond at the diamond(100)/Al(111)interface and improve the interfacial adhesion work.In addition,the diamond/Al composites are fabricated by vacuum gas pressure infiltration,and multi-scale characterization of the interface structure of diamond/Al composites is carried out.The interfacial debonding occurs mainly on the diamond{111}.Meanwhile,the interface product Al_(4)C_(3) is easier to form on the diamond{100}.The experimental phenomenon is consistent with the calculated results.Moreover,the influence of the interfacial reaction on the properties and stability of diamond/Al composites are further discussed through heat-moisture treatment.The study finds that the performance degradation in heat-moisture environment is related mainly to the hydrolysis of the interface product Al_(4)C_(3).After 60 days’heatmoisture,the thermal conductivity of the diamond/Al composites decreases by 29.9%,and the bending strength is reduced by 40.1%.The large attenuation of performance is not conducive to the stability of composites in complex environments.Therefore,inhibiting the formation of Al_(4)C_(3) and improving interfacial selectivity are of great importance in developing the performance and stability of diamond/Al composites.The research in this paper not only lays a theoretical foundation for the first-principles calculation of the interface properties of diamond/metal,but also possesses important guidance significance in designing the diamond/metal composites.
作者
祝平
张强
芶华松
王平平
邵溥真
小林郁夫
武高辉
Zhu Ping;Zhang Qiang;Gou Hua-Song;Wang Ping-Ping;Shao Pu-Zhen;Kobayashi Equo;Wu Gao-Hui(School of Materials Science and Engineering,Harbin Institute of Technology,Harbin 150001,China;Key Laboratory of Advanced Structure-Function Integrated Materials and Green Manufacturing Technology,Harbin Institute of Technology,Harbin 150001,China;Department of Materials Science and Engineering,Tokyo Institute of Technology,Tokyo 152-8550,Japan)
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2021年第17期257-267,共11页
Acta Physica Sinica
基金
国家自然科学基金(批准号:52071117,51771063)资助的课题.
关键词
金刚石/铝
第一性原理
界面性质
湿热处理
diamond/Al
first-principles
interface properties
heat-moisture treatment
