中國(guó)材料名師講壇第112講——David Srolovitz 院士
主講人：美國(guó)國(guó)家工程院院士 David Srolovitz教授
時(shí)間：2023年5月31日14：00
地點(diǎn)：北京科技大學(xué) 學(xué)術(shù)報(bào)告廳
題目：A General Approach to Interfaces in Crystalline Solids: Precipitate morphology, microstructure evolution, and dislocation-interactions
David Srolovitz院士簡(jiǎn)介：
David Srolovitz教授發(fā)表了約550篇關(guān)于材料理論和晶體缺陷模擬、微觀(guān)結(jié)構(gòu)、變形、薄膜生長(zhǎng)、相變、熱力學(xué)以及相關(guān)研究方法的論文，h指數(shù)為105，獲得40000余次引用。他是美國(guó)國(guó)家工程院院士，MRS、TMS、ASM、IOP會(huì)士，也是MRS材料理論獎(jiǎng)的得主；曾是普林斯頓大學(xué)、賓夕法尼亞大學(xué)和香港城市大學(xué)等知名大學(xué)的教授，在材料科學(xué)、機(jī)械工程、航天工程、計(jì)算機(jī)科學(xué)和物理學(xué)等領(lǐng)域擔(dān)任過(guò)教職。目前的研究興趣集中在材料界面的結(jié)構(gòu)、熱力學(xué)、動(dòng)力學(xué)等性質(zhì)、位錯(cuò)、晶粒生長(zhǎng)以及這些缺陷對(duì)材料的力學(xué)行為、光電性質(zhì)和輻照損傷的影響；開(kāi)發(fā)了第一性原理、原子尺度、缺陷動(dòng)力學(xué)、微觀(guān)結(jié)構(gòu)和連續(xù)介質(zhì)模型的材料模擬新技術(shù)以及多尺度模擬方法。
摘要：
Since single crystals are rare, interfaces are inherent features of almost all natural and engineering materials. Their behavior determine a wide range of material properties. This includes both homo-phase (grain boundaries) and hetero-phase (multiphase materials). Most interface properties are, unsurprisingly, related to their structures. I will first present a general description of interfaces and their defects-based on some simple crystallographic ideas. The most important interface defects are disconnections; line defects with both dislocation and step character. Next, I will use these ideas to generalize the famous Frank-Bilby equation, to predict orientation relationships (ORs) between matrixes and precipitates; i.e., relative orientations of two crystalline phases and interface orientations. I will then describe how to go from a disconnection picture of interface migration to continuum descriptions of microstructure evolution (interface faceting, precipitate morphology evolution, and grain growth). Finally, I will analyze how dislocations in bulk phases interact with interfaces including dislocation blocking (Hall-Petch behavior), absorption, reflection, transmission and interface sliding. Comparison with experimental observations will be made throughout.