【《稀土元素在镁晶界处偏析的第一性原理研究文献综述》5200字】

稀土元素在镁晶界处偏析的第一性原理研究文献综述目录TOC\o"1-3"\h\u22509稀土元素在镁晶界处偏析的第一性原理研究文献综述 120071稀土镁合金概述 1125362元素在晶界偏析的强化机制 3214833国内外发展现状 5近年来，镁合金发展迅速，其缺点也慢慢展现，即塑性成形性和抗腐蚀性较差，于是研究学者提出了多种镁合金的强化方法，如合金化、塑性变形和热处理等强化手段。在众多方法之中，利用稀土元素在镁晶界处的偏析以强化晶界的强化手段脱颖而出。这种方法能够有针对性地改善镁合金的塑性，有效拓宽镁合金的应用范围。但是，用传统的实验研究手段很难完整地做出元素在镁晶界偏析实验过程，而且后续的观察分析都较为困难，无法从微观角度分析其强化力度和强化机制，非常消耗时间成本和人工成本。于是，有人提出通过第一性原理研究的手段来模拟元素在晶界处的偏析，这样能够实现高效率、低成本且有针对性的实验研究。1稀土镁合金概述稀土元素和镁矿在我国都属于优势资源，其中，我国镁资源约占世界储量的百分之七十ADDINEN.CITE<EndNote><Cite><Author>冀丽安</Author><Year>2020</Year><RecNum>38</RecNum><DisplayText><styleface="superscript">[20]</style></DisplayText><record><rec-number>38</rec-number><foreign-keys><keyapp="EN"db-id="rdze5zzau99z5cevfr0vv054ex0pwe9wsptr"timestamp="1622393035">38</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>冀丽安</author></authors></contributors><titles><title>镁合金及稀土镁合金浅析</title><secondary-title>稀土信息</secondary-title></titles><periodical><full-title>稀土信息</full-title></periodical><pages>34-38</pages><number>05</number><keywords><keyword>稀土镁合金</keyword><keyword>变形镁合金</keyword><keyword>稀土元素</keyword></keywords><dates><year>2020</year></dates><isbn>2096-353X</isbn><call-num>15-1100/TF</call-num><urls></urls><remote-database-provider>Cnki</remote-database-provider></record></Cite></EndNote>[20]。因此在我国发展稀土镁合金无疑具有得天独厚的优势。大量研究证明，在镁合金中加入稀土元素可以有效做到细化晶粒和弱化织构ADDINEN.CITE<EndNote><Cite><Author>李波</Author><RecNum>37</RecNum><DisplayText><styleface="superscript">[21]</style></DisplayText><record><rec-number>37</rec-number><foreign-keys><keyapp="EN"db-id="rdze5zzau99z5cevfr0vv054ex0pwe9wsptr"timestamp="1622392804">37</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>李波</author><author>刘峰</author><author>胡文鑫</author></authors></contributors><auth-address>包头稀土研究院白云鄂博稀土资源研究与综合利用国家重点实验室;</auth-address><titles><title>轻稀土资源在镁合金中的应用及研究进展</title><secondary-title>稀土</secondary-title></titles><periodical><full-title>稀土</full-title></periodical><pages>1-7</pages><keywords><keyword>稀土</keyword><keyword>镁合金</keyword><keyword>强塑性</keyword><keyword>耐热性</keyword><keyword>耐腐蚀性</keyword><keyword>导热系数</keyword></keywords><dates></dates><isbn>1004-0277</isbn><call-num>15-1099/TF</call-num><urls></urls><remote-database-provider>Cnki</remote-database-provider></record></Cite></EndNote>[21]。这恰恰可以针对性地改善镁合金的不足，即塑性差、强度低。稀土元素是镧系元素的简称，非常活泼，按照原子量可以分为三类，分别为轻稀土元素、中稀土元素和重稀土元素。稀土元素的加入可以使镁合金的力学性能迅速提升，主要是从四个方面来改善其性能，分别是净化作用、活化作用、细化作用和合金化作用ADDINEN.CITE<EndNote><Cite><Author>王红炜</Author><Year>2017</Year><RecNum>41</RecNum><DisplayText><styleface="superscript">[22]</style></DisplayText><record><rec-number>41</rec-number><foreign-keys><keyapp="EN"db-id="rdze5zzau99z5cevfr0vv054ex0pwe9wsptr"timestamp="1622395857">41</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>王红炜</author><author>胡延明</author><author>连珍锐</author></authors></contributors><auth-address>中国京冶工程技术有限公司;</auth-address><titles><title>稀土元素对镁合金产品的强化浅析</title><secondary-title>金属世界</secondary-title></titles><periodical><full-title>金属世界</full-title></periodical><pages>9-13</pages><number>01</number><keywords><keyword>镁合金</keyword><keyword>微观组织</keyword><keyword>稀土元素</keyword><keyword>镁合金材料</keyword></keywords><dates><year>2017</year></dates><isbn>1000-6826</isbn><call-num>11-1417/TG</call-num><urls></urls><remote-database-provider>Cnki</remote-database-provider></record></Cite></EndNote>[22]。其一，稀土元素活性高，可以与多种杂质发生反应，起到很好地净化作用。其二，稀土元素可以作为合金的表面活性元素，这一点能够很好地针对性改善镁合金塑性差的问题，使镁合金铸造时的流动性增强。这为镁合金的加工成形提供了很好的便捷之处。其三，稀土元素的加入可以促进晶粒细化，有效改善镁合金性能。其四，在需要添加其他元素时，稀土元素也能够很好的同添加元素形成金属间化合物，这样一来，镁合金的铸造性能能够得到很大的改善。目前在稀土镁合金应用时常使用的稀土元素及其作用机制如下表1.4所示ADDINEN.CITE<EndNote><Cite><Author>樊振中</Author><Year>2020</Year><RecNum>5</RecNum><DisplayText><styleface="superscript">[5]</style></DisplayText><record><rec-number>5</rec-number><foreign-keys><keyapp="EN"db-id="rdze5zzau99z5cevfr0vv054ex0pwe9wsptr"timestamp="1621320153">5</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>樊振中</author><author>陈军洲</author><author>陆政</author><author>熊艳才</author></authors></contributors><auth-address>中国航发北京航空材料研究院;北京市先进铝合金材料及应用工程技术研究中心;</auth-address><titles><title>镁合金的研究现状与发展趋势</title><secondary-title>铸造</secondary-title></titles><periodical><full-title>铸造</full-title></periodical><pages>1016-1029</pages><volume>69</volume><number>10</number><keywords><keyword>镁合金</keyword><keyword>研究现状</keyword><keyword>发展趋势</keyword><keyword>表面防护</keyword><keyword>微观组织</keyword><keyword>力学性能</keyword></keywords><dates><year>2020</year></dates><isbn>1001-4977</isbn><call-num>21-1188/TG</call-num><urls></urls><remote-database-provider>Cnki</remote-database-provider></record></Cite></EndNote>[5]。稀土镁合金统称为Mg-RE合金，这些合金普遍具有优异的高温力学性能和抗蠕变性能。目前，通过添加稀土元素可以实现多种强化手段ADDINEN.CITE<EndNote><Cite><Author>董天宇</Author><Year>2018</Year><RecNum>40</RecNum><DisplayText><styleface="superscript">[23]</style></DisplayText><record><rec-number>40</rec-number><foreign-keys><keyapp="EN"db-id="rdze5zzau99z5cevfr0vv054ex0pwe9wsptr"timestamp="1622395325">40</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>董天宇</author></authors></contributors><auth-address>河北省特种设备监督检验研究院廊坊分院;</auth-address><titles><title>高性能稀土镁合金研究与应用进展</title><secondary-title>世界有色金属</secondary-title></titles><periodical><full-title>世界有色金属</full-title></periodical><pages>156-157</pages><number>19</number><keywords><keyword>稀土镁合金</keyword><keyword>应用</keyword><keyword>发展</keyword></keywords><dates><year>2018</year></dates><isbn>1002-5065</isbn><call-num>11-2472/TF</call-num><urls></urls><remote-database-provider>Cnki</remote-database-provider></record></Cite></EndNote>[23]，如固溶强化、细晶强化、弥散强化等，都可以对镁合金进行有效的强化。表1.4镁合金常用的稀土添加元素及其作用机制ADDINEN.CITE<EndNote><Cite><Author>樊振中</Author><Year>2020</Year><RecNum>5</RecNum><DisplayText><styleface="superscript">[5]</style></DisplayText><record><rec-number>5</rec-number><foreign-keys><keyapp="EN"db-id="rdze5zzau99z5cevfr0vv054ex0pwe9wsptr"timestamp="1621320153">5</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>樊振中</author><author>陈军洲</author><author>陆政</author><author>熊艳才</author></authors></contributors><auth-address>中国航发北京航空材料研究院;北京市先进铝合金材料及应用工程技术研究中心;</auth-address><titles><title>镁合金的研究现状与发展趋势</title><secondary-title>铸造</secondary-title></titles><periodical><full-title>铸造</full-title></periodical><pages>1016-1029</pages><volume>69</volume><number>10</number><keywords><keyword>镁合金</keyword><keyword>研究现状</keyword><keyword>发展趋势</keyword><keyword>表面防护</keyword><keyword>微观组织</keyword><keyword>力学性能</keyword></keywords><dates><year>2020</year></dates><isbn>1001-4977</isbn><call-num>21-1188/TG</call-num><urls></urls><remote-database-provider>Cnki</remote-database-provider></record></Cite></EndNote>[5]稀土元素作用机制La细化剂与变质剂，细化晶粒，提高力学性能，改善耐蚀性与阻燃性能Ce细化晶粒与网状共晶体，合金纯净化，固溶强化，提高综合力学性能Nd细化晶粒,改善耐热性能，提高力学性能Gd改善微观组织，提高合金室温、高温强度Y细化轧制态微观组织，改善高温力学性能和蠕变性能，提高综合力学性能混合稀土细化晶粒组织，改善抗高温蠕变、摩擦磨损、疲劳性能、阻燃性能，改变强化相的尺寸形貌、取向与析出密度，随添加的含量先上升后下降RE元素在镁合金制备的过程中，有稀土相的形成。这些稀土相多为细小颗粒状，在镁合金中弥散分布，而且多分布在晶粒和晶界上ADDINEN.CITE<EndNote><Cite><Author>张帅</Author><Year>2019</Year><RecNum>46</RecNum><DisplayText><styleface="superscript">[24]</style></DisplayText><record><rec-number>46</rec-number><foreign-keys><keyapp="EN"db-id="rdze5zzau99z5cevfr0vv054ex0pwe9wsptr"timestamp="1622485410">46</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>张帅</author><author>李全安</author><author>朱宏喜</author><author>陈晓亚</author></authors></contributors><auth-address>河南科技大学材料科学与工程学院;有色金属共性技术河南省协同创新中心;西安理工大学材料科学与工程学院;</auth-address><titles><title>Mg-Gd-Y系镁合金的腐蚀与防护研究进展</title><secondary-title>材料保护</secondary-title></titles><periodical><full-title>材料保护</full-title></periodical><pages>158-165</pages><volume>52</volume><number>08</number><keywords><keyword>Mg-Gd-Y</keyword><keyword>镁合金</keyword><keyword>腐蚀</keyword><keyword>防护</keyword><keyword>研究进展</keyword></keywords><dates><year>2019</year></dates><isbn>1001-1560</isbn><call-num>42-1215/TB</call-num><urls></urls><remote-database-provider>Cnki</remote-database-provider></record></Cite></EndNote>[24]。本文中研究的就是在稀土元素Gd和Nd在镁孪晶界面{1011}处的偏析对晶界性能的影响。根据过去研究总结来看，稀土相可以对晶界进行非常好的钉扎，这能够阻碍变形过程中位错的运动，通过弥散强化很好地改善材料的性能。在这些稀土元素之中，Y，Gd，Nd和Sc等在镁合金中具有很好的固溶度和析出强化作用ADDINEN.CITE<EndNote><Cite><Author>杨力祥</Author><Year>2019</Year><RecNum>39</RecNum><DisplayText><styleface="superscript">[25]</style></DisplayText><record><rec-number>39</rec-number><foreign-keys><keyapp="EN"db-id="rdze5zzau99z5cevfr0vv054ex0pwe9wsptr"timestamp="1622394702">39</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>杨力祥</author><author>肖旅</author><author>周海涛</author><author>田莹</author><author>李飞</author><author>曾小勤</author><author>孙宝德</author><author>李中权</author></authors></contributors><auth-address>上海航天精密机械研究所;上海市先进高温材料及其精密成形重点实验室;上海交通大学轻合金精密成型国家工程研究中心;</auth-address><titles><title>高强耐热稀土镁合金研究进展</title><secondary-title>上海航天</secondary-title></titles><periodical><full-title>上海航天</full-title></periodical><pages>38-44</pages><volume>36</volume><number>02</number><keywords><keyword>高强</keyword><keyword>耐热</keyword><keyword>稀土</keyword><keyword>镁合金</keyword><keyword>铸造</keyword></keywords><dates><year>2019</year></dates><isbn>1006-1630</isbn><call-num>31-1481/V</call-num><urls></urls><remote-database-provider>Cnki</remote-database-provider></record></Cite></EndNote>[25]。图1.9Mg-Gd二元相图ADDINEN.CITE<EndNote><Cite><Author>张帅</Author><Year>2019</Year><RecNum>46</RecNum><DisplayText><styleface="superscript">[24]</style></DisplayText><record><rec-number>46</rec-number><foreign-keys><keyapp="EN"db-id="rdze5zzau99z5cevfr0vv054ex0pwe9wsptr"timestamp="1622485410">46</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>张帅</author><author>李全安</author><author>朱宏喜</author><author>陈晓亚</author></authors></contributors><auth-address>河南科技大学材料科学与工程学院;有色金属共性技术河南省协同创新中心;西安理工大学材料科学与工程学院;</auth-address><titles><title>Mg-Gd-Y系镁合金的腐蚀与防护研究进展</title><secondary-title>材料保护</secondary-title></titles><periodical><full-title>材料保护</full-title></periodical><pages>158-165</pages><volume>52</volume><number>08</number><keywords><keyword>Mg-Gd-Y</keyword><keyword>镁合金</keyword><keyword>腐蚀</keyword><keyword>防护</keyword><keyword>研究进展</keyword></keywords><dates><year>2019</year></dates><isbn>1001-1560</isbn><call-num>42-1215/TB</call-num><urls></urls><remote-database-provider>Cnki</remote-database-provider></record></Cite></EndNote>[24]下面以Mg-Gd和Mg-Y合金为例，浅谈其对镁合金的强化作用。Gd是重稀土元素，和Mg一样为密排六方结构，在Mg中的固溶度很大，最高可达到23.5%，如图1.9所示ADDINEN.CITE<EndNote><Cite><Author>张帅</Author><Year>2019</Year><RecNum>46</RecNum><DisplayText><styleface="superscript">[24]</style></DisplayText><record><rec-number>46</rec-number><foreign-keys><keyapp="EN"db-id="rdze5zzau99z5cevfr0vv054ex0pwe9wsptr"timestamp="1622485410">46</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>张帅</author><author>李全安</author><author>朱宏喜</author><author>陈晓亚</author></authors></contributors><auth-address>河南科技大学材料科学与工程学院;有色金属共性技术河南省协同创新中心;西安理工大学材料科学与工程学院;</auth-address><titles><title>Mg-Gd-Y系镁合金的腐蚀与防护研究进展</title><secondary-title>材料保护</secondary-title></titles><periodical><full-title>材料保护</full-title></periodical><pages>158-165</pages><volume>52</volume><number>08</number><keywords><keyword>Mg-Gd-Y</keyword><keyword>镁合金</keyword><keyword>腐蚀</keyword><keyword>防护</keyword><keyword>研究进展</keyword></keywords><dates><year>2019</year></dates><isbn>1001-1560</isbn><call-num>42-1215/TB</call-num><urls></urls><remote-database-provider>Cnki</remote-database-provider></record></Cite></EndNote>[24]。此外，Mg-Gd合金质量轻、强度高，耐热性很好ADDINEN.CITE<EndNote><Cite><Author>唐昌平</Author><Year>2018</Year><RecNum>64</RecNum><DisplayText><styleface="superscript">[26]</style></DisplayText><record><rec-number>64</rec-number><foreign-keys><keyapp="EN"db-id="rdze5zzau99z5cevfr0vv054ex0pwe9wsptr"timestamp="1622599766">64</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>唐昌平</author><author>左国良</author><author>李志云</author><author>孙玹琪</author><author>李权</author></authors></contributors><auth-address>湖南科技大学材料科学与工程学院;高温耐磨材料及制备技术湖南省国防科技重点实验室;株洲六零八所科技有限公司;重庆市科学技术研究院;</auth-address><titles><title>Mg-Gd系合金的合金化研究进展</title><secondary-title>材料导报</secondary-title></titles><periodical><full-title>材料导报</full-title></periodical><pages>3760-3767</pages><volume>32</volume><number>21</number><keywords><keyword>Mg-Gd合金</keyword><keyword>合金化</keyword><keyword>微观组织</keyword><keyword>力学性能</keyword></keywords><dates><year>2018</year></dates><isbn>1005-023X</isbn><call-num>50-1078/TB</call-num><urls></urls><remote-database-provider>Cnki</remote-database-provider></record></Cite></EndNote>[26]。根据Basu等人ADDINEN.CITE<EndNote><Cite><Author>Basu</Author><Year>2016</Year><RecNum>57</RecNum><DisplayText><styleface="superscript">[27]</style></DisplayText><record><rec-number>57</rec-number><foreign-keys><keyapp="EN"db-id="rdze5zzau99z5cevfr0vv054ex0pwe9wsptr"timestamp="1622559808">57</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>I.Basu</author><author>K.G.Pradeep</author><author>C.Mießen</author><author>L.A.Barrales-Mora</author><author>T.Al-Samman</author></authors></contributors><auth-address>InstitutfürMetallkundeundMetallphysik,RWTHAachenUniversity,52056Aachen,Germany;;MaterialsChemistry,RWTHAachenUniversity,D-52074Aachen,Germany</auth-address><titles><title>Theroleofatomicscalesegregationindesigninghighlyductilemagnesiumalloys</title><secondary-title>ActaMaterialia</secondary-title></titles><periodical><full-title>ActaMaterialia</full-title></periodical><volume>116</volume><keywords><keyword>Recrystallization</keyword><keyword>Graingrowth</keyword><keyword>Grainboundarysegregation</keyword><keyword>Texture</keyword><keyword>Atomprobetomography</keyword></keywords><dates><year>2016</year></dates><isbn>1359-6454</isbn><urls></urls><remote-database-provider>Cnki</remote-database-provider></record></Cite></EndNote>[27]的研究表明，Mg-Gd合金表现出了很好地抗拉强度和延展性，加入稀土元素是调整镁合金组织的有效机制。在此基础上，Basu提出利用晶界特征，完成稀土元素在晶界的偏析，这样可以更好地改善镁合金力学性能。Y的原子序数为39，在利用稀土元素改善镁合金性能方向，Y可以说是应用最多、研究最广的稀土元素。Y在Mg中的最大固溶度为12.4%，如下图1.10所示ADDINEN.CITE<EndNote><Cite><Author>陈雷雷</Author><Year>2015</Year><RecNum>47</RecNum><DisplayText><styleface="superscript">[28]</style></DisplayText><record><rec-number>47</rec-number><foreign-keys><keyapp="EN"db-id="rdze5zzau99z5cevfr0vv054ex0pwe9wsptr"timestamp="1622486960">47</key></foreign-keys><ref-typename="Thesis">32</ref-type><contributors><authors><author>陈雷雷</author></authors></contributors><titles><title>Mg-Gd-Y-(Sr)-Zr合金组织和性能的研究</title></titles><keywords><keyword>镁合金</keyword><keyword>锶元素掺加</keyword><keyword>晶粒细化</keyword><keyword>金相结构</keyword></keywords><dates><year>2015</year></dates><publisher>河南科技大学</publisher><work-type>硕士</work-type><urls><related-urls><url>/thesis/ChJUaGVzaXNOZXdTMjAyMTA1MTkSCUQwMTE0MTIxMhoIOTNmamhuOTE%3D</url></related-urls></urls><remote-database-provider>北京万方数据股份有限公司</remote-database-provider><language>chi</language></record></Cite></EndNote>[28]。经过多年稀土元素强化机制的研究，Mg-Gd和Mg-Y合金都已经投入了生产和应用。可以说，稀土镁合金具有广阔的发展前景。如图1.9所示，Gd能够在固溶过程中生成多种稳定性很高的化合物，结合表1.4可知，Gd还能够很好地改善微观组织。而且，Mg-Gd合金是众多合金中综合性能较为优异的合金。因此，本文选择Gd和Nd这两种稀土元素作为主要研究对象，研究其在镁晶界处的偏析对其力学性能的影响。图1.9Mg-Y二元相图ADDINEN.CITE<EndNote><Cite><Author>陈雷雷</Author><Year>2015</Year><RecNum>47</RecNum><DisplayText><styleface="superscript">[28]</style></DisplayText><record><rec-number>47</rec-number><foreign-keys><keyapp="EN"db-id="rdze5zzau99z5cevfr0vv054ex0pwe9wsptr"timestamp="1622486960">47</key></foreign-keys><ref-typename="Thesis">32</ref-type><contributors><authors><author>陈雷雷</author></authors></contributors><titles><title>Mg-Gd-Y-(Sr)-Zr合金组织和性能的研究</title></titles><keywords><keyword>镁合金</keyword><keyword>锶元素掺加</keyword><keyword>晶粒细化</keyword><keyword>金相结构</keyword></keywords><dates><year>2015</year></dates><publisher>河南科技大学</publisher><work-type>硕士</work-type><urls><related-urls><url>/thesis/ChJUaGVzaXNOZXdTMjAyMTA1MTkSCUQwMTE0MTIxMhoIOTNmamhuOTE%3D</url></related-urls></urls><remote-database-provider>北京万方数据股份有限公司</remote-database-provider><language>chi</language></record></Cite></EndNote>[28]2元素在晶界偏析的强化机制实际上，材料的低塑性和低强度等较差力学性能与材料内存在的缺陷密切相关。不论是金属、金属间化合物，还是陶瓷等各类材料，点、线、面这些却缺陷的存在都会显著改变晶体的性质ADDINEN.CITE<EndNote><Cite><Author>Mahjoub</Author><Year>2018</Year><RecNum>60</RecNum><DisplayText><styleface="superscript">[29]</style></DisplayText><record><rec-number>60</rec-number><foreign-keys><keyapp="EN"db-id="rdze5zzau99z5cevfr0vv054ex0pwe9wsptr"timestamp="1622563769">60</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>RezaMahjoub</author><author>KevinJ.Laws</author><author>NikkiStanford</author><author>MichaelFerry</author></authors></contributors><auth-address>FutureIndustryInstitute,UniversityofSouthAustralia,MawsonLakes,SA5095,Australia;;SchoolofMaterialsScienceandEngineering,TheUniversityofNewSouthWales(UNSWSydney),Sydney,NSW2052,Australia</auth-address><titles><title>Generaltrendsbetweensolutesegregationtendencyandgrainboundarycharacterinaluminum-Anabinitostudy</title><secondary-title>ActaMaterialia</secondary-title></titles><periodical><full-title>ActaMaterialia</full-title></periodical><volume>158</volume><keywords><keyword>Grainboundaryengineering</keyword><keyword>Segregationenergy</keyword><keyword>Cohesion</keyword><keyword>Polycrystallinestability</keyword><keyword>Generaltrends</keyword><keyword>Abinitio</keyword><keyword>Electronicstructure</keyword></keywords><dates><year>2018</year></dates><isbn>1359-6454</isbn><urls></urls><remote-database-provider>Cnki</remote-database-provider></record></Cite></EndNote>[29]。在评判材料制备优劣和性能好坏时，其缺陷是一个重要指标。这是因为缺陷的运动与迁移能够直接导致材料的失效。相反，如果利用缺陷运动的特征针对性地阻止材料失效，就可以很好地改善材料的力学性能。比如，晶界就可以影响材料的力学性能和动力学性能等。晶界是一种主要的面缺陷，晶界与相邻晶粒的内部组织有很大的区别ADDINEN.CITE<EndNote><Cite><Author>Mahjoub</Author><Year>2018</Year><RecNum>60</RecNum><DisplayText><styleface="superscript">[29]</style></DisplayText><record><rec-number>60</rec-number><foreign-keys><keyapp="EN"db-id="rdze5zzau99z5cevfr0vv054ex0pwe9wsptr"timestamp="1622563769">60</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>RezaMahjoub</author><author>KevinJ.Laws</author><author>NikkiStanford</author><author>MichaelFerry</author></authors></contributors><auth-address>FutureIndustryInstitute,UniversityofSouthAustralia,MawsonLakes,SA5095,Australia;;SchoolofMaterialsScienceandEngineering,TheUniversityofNewSouthWales(UNSWSydney),Sydney,NSW2052,Australia</auth-address><titles><title>Generaltrendsbetweensolutesegregationtendencyandgrainboundarycharacterinaluminum-Anabinitostudy</title><secondary-title>ActaMaterialia</secondary-title></titles><periodical><full-title>ActaMaterialia</full-title></periodical><volume>158</volume><keywords><keyword>Grainboundaryengineering</keyword><keyword>Segregationenergy</keyword><keyword>Cohesion</keyword><keyword>Polycrystallinestability</keyword><keyword>Generaltrends</keyword><keyword>Abinitio</keyword><keyword>Electronicstructure</keyword></keywords><dates><year>2018</year></dates><isbn>1359-6454</isbn><urls></urls><remote-database-provider>Cnki</remote-database-provider></record></Cite></EndNote>[29]，因此，晶界是影响材料机械性能、物理性能、抗腐蚀性能的关键。研究发现，当原子在晶界发生偏析时，可以显著改善材料热稳定性和力学行为ADDINEN.CITE<EndNote><Cite><Author>Huang</Author><Year>2018</Year><RecNum>58</RecNum><DisplayText><styleface="superscript">[30]</style></DisplayText><record><rec-number>58</rec-number><foreign-keys><keyapp="EN"db-id="rdze5zzau99z5cevfr0vv054ex0pwe9wsptr"timestamp="1622560303">58</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>ZhifengHuang</author><author>FeiChen</author><author>QiangShen</author><author>LianmengZhang</author><author>TimothyJ.Rupert</author></authors></contributors><auth-address>StateKeyLabofAdvancedTechnologyforMaterialsSynthesisandProcessing,WuhanUniversityofTechnology,Wuhan430070,China;;DepartmentofMechanicalandAerospaceEngineering,UniversityofCalifornia,Irvine,CA92697,USA;;DepartmentofChemicalEngineeringandMaterialsScience,UniversityofCalifornia,Irvine,CA92697,USA</auth-address><titles><title>UncoveringtheinfluenceofcommonnonmetallicimpuritiesonthestabilityandstrengthofaΣ5(310)grainboundaryinCu</title><secondary-title>ActaMaterialia</secondary-title></titles><periodical><full-title>ActaMaterialia</full-title></periodical><volume>148</volume><keywords><keyword>Grainboundaries</keyword><keyword>Impuritysegregation</keyword><keyword>Thermodynamicstability</keyword><keyword>Embrittlement</keyword><keyword>First-principlescalculations</keyword></keywords><dates><year>2018</year></dates><isbn>1359-6454</isbn><urls></urls><remote-database-provider>Cnki</remote-database-provider></record></Cite></EndNote>[30]。本文中的研究对象镁合金具有密排六方结构，相较于铝合金和钢铁材料来说，镁合金的强化手段非常有限。目前广泛认为，合金化是提高具有HCP结构的金属性能的有效方法之一。在这之中，溶质在孪晶界面处的偏析被认为是极其重要的强化手段ADDINEN.CITE<EndNote><Cite><Author>Reza</Author><Year>2019</Year><RecNum>52</RecNum><DisplayText><styleface="superscript">[31]</style></DisplayText><record><rec-number>52</rec-number><foreign-keys><keyapp="EN"db-id="rdze5zzau99z5cevfr0vv054ex0pwe9wsptr"timestamp="1622540201">52</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>MahjoubReza</author><author>FerryMichael</author><author>StanfordNikki</author></authors></contributors><titles><title>LocaltopologyanditseffectsongrainboundaryandsolutesegregationinHCPmagnesium</title><secondary-title>Elsevier</secondary-title></titles><periodical><full-title>Elsevier</full-title></periodical><volume>6</volume><dates><year>2019</year></dates><isbn>2589-1529</isbn><urls></urls><remote-database-provider>Cnki</remote-database-provider></record></Cite></EndNote>[31]。镁合金的强化手段有很多，但是，镁合金的高强度和延展性却难以同时实现，而溶质原子在晶界处的偏析可以帮助释放位错产生的能量，细化晶粒，同时改善镁合金的强度和塑性ADDINEN.CITE<EndNote><Cite><Author>Pan</Author><Year>2020</Year><RecNum>54</RecNum><DisplayText><styleface="superscript">[32]</style></DisplayText><record><rec-number>54</rec-number><foreign-keys><keyapp="EN"db-id="rdze5zzau99z5cevfr0vv054ex0pwe9wsptr"timestamp="1622541446">54</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>HuchengPan</author><author>RuiKang</author><author>JingrenLi</author><author>HongboXie</author><author>ZhuoranZeng</author><author>QiuyanHuang</author><author>ChanglinYang</author><author>YupingRen</author><author>GaowuQin</author></authors></contributors><auth-address>KeyLaboratoryforAnisotropyandTextureofMaterials(MoE),SchoolofMaterialsScienceandEngineering,NortheasternUniversity,Shenyang110819,China;;StateKeyLaboratoryofRollingandAutomation,NortheasternUniversity,Shenyang110819,China;;DepartmentofMaterialsScienceandEngineering,MonashUniversity,Vic.3800,Australia;;InstituteofMetalResearch,ChineseAcademyofSciences,Shenyang110016,China;;StateKeyLaboratoryofSolidificationProcessing,NorthwesternPolytechnicalUniversity,Xi'an,Shaanxi710072,China</auth-address><titles><title>Mechanisticinvestigationofalow-alloyMg–Ca-basedextrusionalloywithhighstrength–ductilitysynergy</title><secondary-title>ActaMaterialia</secondary-title></titles><periodical><full-title>ActaMaterialia</full-title></periodical><volume>186</volume><keywords><keyword>Mgwroughtalloy</keyword><keyword>Mechanicalproperty</keyword><keyword>Low-anglegrainboundary</keyword><keyword>Dynamicrecrystallisation</keyword><keyword>Pyramidaldislocations</keyword></keywords><dates><year>2020</year></dates><isbn>1359-6454</isbn><urls></urls><remote-database-provider>Cnki</remote-database-provider></record></Cite></EndNote>[32]。晶界作为一种面缺陷，经常作为很多重要材料强化方法的研究对象，其性能与材料整体的力学性能息息相关。从Hall-Petch强化到裂纹形成，晶界的演化对材料的宏观性能起着至关重要的作用ADDINEN.CITE<EndNote><Cite><Author>Huber</Author><Year>2017</Year><RecNum>48</RecNum><DisplayText><styleface="superscript">[33]</style></DisplayText><record><rec-number>48</rec-number><foreign-keys><keyapp="EN"db-id="rdze5zzau99z5cevfr0vv054ex0pwe9wsptr"timestamp="1622536805">48</key></foreign-keys><ref-typename="JournalArticle">17</ref-type><contributors><authors><author>LiamHuber</author><author>BlazejGrabowski</author><author>MatthiasMilitzer</author><author>JörgNeugebauer</author><author>JörgRottler</author></authors></contributors><auth-address>Max-Planck-InstitutfürEisenforschungGmbH,D-40237,Düsseldorf,Germany;;CentreforMetallurgicalProcessEngineering,TheUniversityofBritishColumbia,309-6350StoresRoad,Vancouver,BC,V6T1Z4,Canada;;DepartmentofPhysicsandAstronomy,TheUniversityofBritishColumbia,6224AgriculturalRd.,Vancouver,BC,V6T1Z1,Canada</auth-address><titles><title>Abinitiomodellingofsolutesegregationenergiestoageneralgrainboundary</title><secondary-title>ActaMaterialia</secondary-title></titles><periodical><full-title>ActaMaterialia</full-title></periodical><volume>132</volume><keywords><keyword>Abinitiomodelling</keyword><keyword>Multiscalemodelling</keyword><keyword>Grainboundary</keyword><keyword>Solutesegregation</keyword></keywords><dates><year>2017</year></dates><isbn>1359-6454</isbn><urls></urls><remote-database-provider>Cnki</remote-database-provider></record></Cite></EndNote>[33]。溶质原子在晶界处的偏析可以很好地缓解晶界上的弹性应变ADDINEN.CITE<EndNote><Cite><Author>李万鹏</Author><Year>2018</Year><RecNum>42</RecNum><DisplayText><styleface="superscript">[34]</style></DisplayText><record><rec-number>42</rec-number><foreign-keys><keyapp="EN"db-id="rdze5zzau99z5cevfr0vv054ex0pwe9wsptr"timestamp="1622397869">42</key></foreign-keys><ref-typename="Thesis">32</ref-type><contributors><authors><author>李万鹏</author></authors><tertiary-authors><author>刘翠秀,</author><author>孙威,</author></tertiary-authors></contributors><titles><title>Mg-Y-Nd合金孪晶界偏析及Mg-Y-Zn合金长周期相室温变形行为研究</title></titles><keywords><keyword>镁合金</keyword><keyword>{10(?)1}孪晶界</keyword><keyword>偏聚</keyword><keyword>长周期相</keyword><keyword>非基面滑移</keyword></keywords><dates><year>2018</year></dates><publisher>北京工业大学</publisher><work-type>硕士</work-type><urls></urls><remote-database-provider>Cnki</remote-database-provider></record></Cite></EndNote>[34]，从结构、能量和结合强度等方面改良晶界的性能从而改善材料的力学性能。此外，通过溶质原子进行“装饰”后，可以使晶界的能量和结合强度发生改变，还有可能会发生局部相变ADDINEN.CITE<EndNote><Cite><Author>Raabe</Author><Year>2014</Year><RecNum>50</RecNum><DisplayText><styleface="superscript">[35]</style></DisplayText><record><rec-number>50</rec-number><foreign-key