E. V. Aryshenskii, M. A. Lapshov, D. Yu. Rasposienko, S. V. Konovalov, A. M. Drits, V. V. Makarov
{"title":"Studying the Effect of Small Additives of Sc and Zr on the Microstructure of Al–Mg–Si Alloy with Excess Silicon during Multi-Step Heat Treatment","authors":"E. V. Aryshenskii, M. A. Lapshov, D. Yu. Rasposienko, S. V. Konovalov, A. M. Drits, V. V. Makarov","doi":"10.1134/s0031918x23602573","DOIUrl":null,"url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The work is devoted to the study of the effect of multi-step heat treatment on the formation of the microstructure of the alloy of Al–Mg–Si series, alloyed with scandium and zirconium at the ratio of Mg/Si = 0.3. For this purpose, the base AlMgSi alloy, containing no scandium and zirconium, as well as its modification AlMgSiScZr with additions of these elements were cast. Multi-step heat treatment of AlMgSiScZr alloy consisted of four steps of annealing: at 550°C for 8 h + at 440°C for 8 h + at 500°C for 0.5 h + at 180°C for 5 h. For AlMgSi alloy, it included two steps: at 550°C for 8 h + at 180°C for 5 h. The microstructure of AlMgSiScZr alloy was studied in the cast state, as well as after each step of heat treatment by scanning and transmission electron microscopy, while AlMgSi alloy was studied in the cast state and after the final heat treatment. After each step of heat treatment, the microhardness of the studied alloys was measured. It was found that during cooling of the ingot, in the alloys under consideration coarse intermetallics of Fe<sub>2</sub>Mg<sub>7</sub>Si<sub>10</sub>Al<sub>18</sub> type were formed, which partially were dissolved during subsequent heat treatment. At the same time, in the alloy with scandium and zirconium additives, particles that can be attributed either to (AlSi)<sub>3</sub>ScZr or to the τ (phase) of AlSc<sub>2</sub>Si<sub>2</sub> are present at the intergranular boundaries. No traces of intermittent decomposition of the scandium supersaturated solid solution during cooling of the ingot were found. Heat treatment at 550°C for 8 h + at 440°C for 8 h leads to the appearance of a phase that can be both AlSc<sub>2</sub>Si<sub>2</sub> and Al<sub>5</sub>SiZr<sub>2</sub>, while no (AlSi)<sub>3</sub>ScZr nanoparticles are formed. Heating at 500°C for 30 min enables complete dissolution of the magnesium-containing particles. At the final step, β\" (Mg<sub>5</sub>Si<sub>6</sub>) particles are formed in the investigated alloys, while scandium has no significant effect on their formation.</p>","PeriodicalId":20180,"journal":{"name":"Physics of Metals and Metallography","volume":"146 1","pages":""},"PeriodicalIF":1.1000,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Physics of Metals and Metallography","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.1134/s0031918x23602573","RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"METALLURGY & METALLURGICAL ENGINEERING","Score":null,"Total":0}
引用次数: 0
Abstract
The work is devoted to the study of the effect of multi-step heat treatment on the formation of the microstructure of the alloy of Al–Mg–Si series, alloyed with scandium and zirconium at the ratio of Mg/Si = 0.3. For this purpose, the base AlMgSi alloy, containing no scandium and zirconium, as well as its modification AlMgSiScZr with additions of these elements were cast. Multi-step heat treatment of AlMgSiScZr alloy consisted of four steps of annealing: at 550°C for 8 h + at 440°C for 8 h + at 500°C for 0.5 h + at 180°C for 5 h. For AlMgSi alloy, it included two steps: at 550°C for 8 h + at 180°C for 5 h. The microstructure of AlMgSiScZr alloy was studied in the cast state, as well as after each step of heat treatment by scanning and transmission electron microscopy, while AlMgSi alloy was studied in the cast state and after the final heat treatment. After each step of heat treatment, the microhardness of the studied alloys was measured. It was found that during cooling of the ingot, in the alloys under consideration coarse intermetallics of Fe2Mg7Si10Al18 type were formed, which partially were dissolved during subsequent heat treatment. At the same time, in the alloy with scandium and zirconium additives, particles that can be attributed either to (AlSi)3ScZr or to the τ (phase) of AlSc2Si2 are present at the intergranular boundaries. No traces of intermittent decomposition of the scandium supersaturated solid solution during cooling of the ingot were found. Heat treatment at 550°C for 8 h + at 440°C for 8 h leads to the appearance of a phase that can be both AlSc2Si2 and Al5SiZr2, while no (AlSi)3ScZr nanoparticles are formed. Heating at 500°C for 30 min enables complete dissolution of the magnesium-containing particles. At the final step, β" (Mg5Si6) particles are formed in the investigated alloys, while scandium has no significant effect on their formation.
期刊介绍：
The Physics of Metals and Metallography (Fizika metallov i metallovedenie) was founded in 1955 by the USSR Academy of Sciences. Its scientific profile involves the theory of metals and metal alloys, their electrical and magnetic properties, as well as their structure, phase transformations, and principal mechanical properties. The journal also publishes scientific reviews and papers written by experts involved in fundamental, application, and technological studies. The annual volume of publications amounts to some 250 papers submitted from 100 leading national scientific institutions.
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号
