{"title":"硅偏析阻止了液态铝基底和 TiB2 基底界面上的预核,这是 \"硅中毒 \"的起源","authors":"","doi":"10.1016/j.scriptamat.2024.116445","DOIUrl":null,"url":null,"abstract":"<div><div>The mechanism of ‘Si poisoning’ of Al-Ti-B based grain-refiners in Al-Si alloys has been a topic of intensive study for over half a century. We here investigate prenucleation of Al at the Si segregated interfaces between liquid Al and TiB<sub>2</sub>{0001} substrates using <em>ab initio</em> techniques. Our study reveals that chemical affinity between Ti and Si atoms empowers Si segregation at the Al(l)/substrate interface during solidification. The Si interfacial segregation curbs atomic ordering in the liquid Al adjacent to the substrate. Consequently, prenucleation of Al atoms at the Al(l)/{0001}TiB<sub>2</sub> interface is deteriorated and thus, the subsequent nucleation process adversely affected, which causes the so-called ‘Si poisoning’ effect during the practice of grain refinement via inoculation with addition of TiB<sub>2</sub> particles in Al-Si alloys.</div></div>","PeriodicalId":423,"journal":{"name":"Scripta Materialia","volume":null,"pages":null},"PeriodicalIF":5.3000,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Si segregation deters prenucleation at the interfaces between liquid-aluminum and TiB2 substrates, the origin of ‘Si poisoning’\",\"authors\":\"\",\"doi\":\"10.1016/j.scriptamat.2024.116445\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>The mechanism of ‘Si poisoning’ of Al-Ti-B based grain-refiners in Al-Si alloys has been a topic of intensive study for over half a century. We here investigate prenucleation of Al at the Si segregated interfaces between liquid Al and TiB<sub>2</sub>{0001} substrates using <em>ab initio</em> techniques. Our study reveals that chemical affinity between Ti and Si atoms empowers Si segregation at the Al(l)/substrate interface during solidification. The Si interfacial segregation curbs atomic ordering in the liquid Al adjacent to the substrate. Consequently, prenucleation of Al atoms at the Al(l)/{0001}TiB<sub>2</sub> interface is deteriorated and thus, the subsequent nucleation process adversely affected, which causes the so-called ‘Si poisoning’ effect during the practice of grain refinement via inoculation with addition of TiB<sub>2</sub> particles in Al-Si alloys.</div></div>\",\"PeriodicalId\":423,\"journal\":{\"name\":\"Scripta Materialia\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":5.3000,\"publicationDate\":\"2024-11-04\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Scripta Materialia\",\"FirstCategoryId\":\"88\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S1359646224004809\",\"RegionNum\":2,\"RegionCategory\":\"材料科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"MATERIALS SCIENCE, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Scripta Materialia","FirstCategoryId":"88","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1359646224004809","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
摘要
半个多世纪以来,人们一直在深入研究铝硅合金中基于铝-钛-B 晶粒的 "硅中毒 "机制。在此,我们使用 ab initio 技术研究了铝在液态铝和 TiB2{0001} 基质之间的硅偏析界面上的预成核现象。我们的研究发现,在凝固过程中,Ti 原子和 Si 原子间的化学亲和力会促进 Al(l)/ 基底界面上的硅偏析。硅界面偏析抑制了邻近基底的液态铝中的原子有序性。因此,Al(l)/{0001}TiB2 界面上的 Al 原子预成核会恶化,从而对随后的成核过程产生不利影响,这就造成了在 Al-Si 合金中通过接种添加 TiB2 粒子进行晶粒细化时的所谓 "Si 中毒 "效应。
Si segregation deters prenucleation at the interfaces between liquid-aluminum and TiB2 substrates, the origin of ‘Si poisoning’
The mechanism of ‘Si poisoning’ of Al-Ti-B based grain-refiners in Al-Si alloys has been a topic of intensive study for over half a century. We here investigate prenucleation of Al at the Si segregated interfaces between liquid Al and TiB2{0001} substrates using ab initio techniques. Our study reveals that chemical affinity between Ti and Si atoms empowers Si segregation at the Al(l)/substrate interface during solidification. The Si interfacial segregation curbs atomic ordering in the liquid Al adjacent to the substrate. Consequently, prenucleation of Al atoms at the Al(l)/{0001}TiB2 interface is deteriorated and thus, the subsequent nucleation process adversely affected, which causes the so-called ‘Si poisoning’ effect during the practice of grain refinement via inoculation with addition of TiB2 particles in Al-Si alloys.
期刊介绍:
Scripta Materialia is a LETTERS journal of Acta Materialia, providing a forum for the rapid publication of short communications on the relationship between the structure and the properties of inorganic materials. The emphasis is on originality rather than incremental research. Short reports on the development of materials with novel or substantially improved properties are also welcomed. Emphasis is on either the functional or mechanical behavior of metals, ceramics and semiconductors at all length scales.