热处理过程中MnO-SiO_(2)-Al_(2)O_(3)基玻璃态夹杂物的结晶行为  

Crystallization behavior of glassy MnO-SiO_(2)-Al_(2)O_(3)-based inclusions during heat treatment

作　　者：雷旭博 徐琦 Rodrigue Ameal Muvuny 黄灵杰 李建立[1,2] LEI Xubo;XU Qi;Rodrigue Ameal Muvuny;HUANG Lingjie;LI Jianli(Key Laboratory of Ferrous Metallurgy and Resource Utilization of Ministry of Education,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China;Hubei Provincial Key Laboratory of New Processes of Ironmaking and Steelmaking,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China)

机构地区：[1]武汉科技大学钢铁冶金及资源利用省部共建教育部重点实验室,湖北武汉430081 [2]武汉科技大学钢铁冶金新工艺湖北省重点实验室,湖北武汉430081

出　　处：《钢铁》2025年第1期66-74,共9页Iron and Steel

基　　金：国家自然科学基金资助项目(52274341)。

摘　　要：结晶态夹杂物相较于玻璃态夹杂物具有更高的硬度,对钢材的轧制及后续加工过程危害更大。为了进一步明确热处理过程中MnO-SiO_(2)-Al_(2)O_(3)基玻璃态夹杂物的结晶行为,在实验室进行了一系列不同MgO含量合成夹杂物的等温结晶试验,利用X射线衍射仪与场发射扫描电子显微镜对热处理后夹杂物的晶相组成以及微观形貌进行分析。结果表明,热处理温度为900℃时,w(MgO)=0、w(MgO)=10%合成夹杂物仍为玻璃态,w(MgO)=20%合成夹杂物在其表面形成MgSiO_(3)和MgMnSi_(2)O_(6)晶相;热处理温度为1000℃时,除w(MgO)=0外合成夹杂物均形成晶相,w(MgO)=10%合成夹杂物中形成了MgSiO_(3)和MgMnSi_(2)O_(6)晶相,w(MgO)=20%合成夹杂物中晶相以MgSiO_(3)和MgMnSi_(2)O_(6)为主,此外还存在少量Mg_(2)SiO_(4)晶相;热处理温度为1100℃时,SiO_(2)、Mn_(3)Al_(2)Si_(3)O_(12)晶相在w(MgO)=0合成夹杂物中析出,w(MgO)=10%、w(MgO)=20%合成夹杂物中主晶相仍为MgSiO_(3)和MgMnSi_(2)O_(6)。热处理过程玻璃态夹杂物中元素扩散富集,最先在夹杂物表面形成晶相,然后向内部生长并伴随着内部晶相的形成与长大聚集,最终向完全结晶态夹杂物转变。随着热处理温度的升高,固态夹杂物中元素的扩散能力增强,晶相形成速度加快,夹杂物的结晶比例上升;随着MgO含量的增加,MnO-SiO_(2)-Al_(2)O_(3)基夹杂物结晶能力增强,玻璃态夹杂物可以在较低的温度发生结晶转变,而且在更高的温度下更容易达到完全结晶;而热处理时间的增加则会使得晶相进一步生长聚集。因此,热处理温度的升高、热处理时间的增加以及夹杂物MgO含量的增加都会促进玻璃态夹杂物向结晶态夹杂物的转变。Crystalline inclusions have higher hardness than glassy inclusions,which is more harmful to the rolling and subsequent processing of steel.To further clarify the crystallization behavior of glassy MnO-SiO_(2)-Al_(2)O_(3)-based inclusions during heat treatment,a series of isothermal crystallization experiments of synthetic inclusions with different MgO contents were carried out in the laboratory,and the crystalline phase and microscopic morphology of inclusions were analyzed by XRD and SEM-EDS.The results show that after heat treatment at 900℃,w(MgO)=0 and w(MgO)=10%synthetic inclusions remain glassy state,and w(MgO)=20%synthetic inclusions form MgSiO_(3)and MgMnSi_(2)O_(6)crystalline phases on the surface of inclusions.When heat treatment temperature is 1000℃,crystalline phases are formed except for w(MgO)=0 synthetic inclusions,and the w(MgO)=10%synthetic inclusions form MgSiO_(3)and MgMnSi_(2)O_(6)crystalline phase,while MgSiO_(3),MgMnSi_(2)O_(6)and a small amount of Mg_(2)SiO_(4)crystalline phase are formed in w(MgO)=20%synthetic inclusions.When heat treatment temperature at 1100℃,SiO_(2)and Mn_(3)Al_(2)Si_(3)O_(12)crystalline phase are formed in w(MgO)=0 synthetic inclusions,while the main crystalline phases in the w(MgO)=10%and w(MgO)=20%synthetic inclusions are MgSiO_(3)and MgMnSi_(2)O_(6).During the heat treatment process,the elements are enriched by diffusion and firstly crystalline phase is formed on the surface of glassy inclusions,then the surface crystalline phase grows internally accompanied by the formation and growth of internal crystalline phase,and eventually transforms to the fully crystalline inclusions.With the increase of heat treatment temperature,the diffusion ability of the elements in the solid inclusions is enhanced,so that the crystalline phase formation rate is accelerated and the crystallization ratio of inclusions rises.Moreover,with the increase of MgO content,the crystallization ability of MnO-SiO_(2)-Al_(2)O_(3)-based inclusions increases,which makes inclusions crystallizati

关 键 词：结晶 夹杂物 固态转变 热处理 MgO 硅锰脱氧钢 玻璃态 MnO-SiO_(2)-Al_(2)O_(3) 

分 类 号：TG142.1[一般工业技术—材料科学与工程] TG156[金属学及工艺—金属材料]