摘要
目的为研究添加Ti对连续热镀铝锌生产过程中熔池悬浮渣形成的影响,探讨添加Ti的熔池锌渣的种类、成分、尺寸、数量的变化特点以及生长机制。方法通过向铝锌熔池添加Ti(钛铝锌合金)的方法,对预熔锅、主锌锅的铝锌熔池液面下方约350 mm位置处的含悬浮渣熔液取样,添加Ti试验结束更换沉没辊时,提取主锌锅的锅沿面渣、底渣样品。采用火花直读光谱仪(S-OES)分析添加Ti前后不同时期的悬浮渣熔液中的Ti含量,采用扫描电子显微镜(SEM)、能谱仪(EDS)对锌渣进行形貌、尺寸、组成及数量分析。结果添加Ti后2 h,预熔锅熔液中出现了较多粒径约10~43μm的椭球形Al-V-Ti系锌渣,其中约80%锌渣的粒径为10~25μm,一些较大的椭球形锌渣相的心部出现大小不等的孔洞。主锌锅熔液添加Ti形成的悬浮渣包括椭球形Al-V-Ti系锌渣和多边形、块状Al-Fe-Si系锌渣,Al-V-Ti系锌渣粒径约为10~50μm,大部分的Al-Fe-Si系锌渣尺寸相比Al-V-Ti系锌渣更大。熔池添加Ti后,锅沿面渣、底渣主要由多边形Al-Fe-Si系锌渣、椭球形Al-V-Ti系锌渣及熔液凝固组织构成,粒径约为10~46μm的Al-V-Ti系锌渣较多,在锅沿面渣、底渣的Al-V-Ti系锌渣中的比例分别为93%、97%,有大约50%的锅沿面渣、底渣的Al-Fe-Si系锌渣粒径分别约为150、200μm。结论预熔锅熔液Ti含量变化较快,主锌锅熔液Ti含量变化较慢,随时间大致呈线性增长。随着主锌锅熔池Ti含量的增加,Al-V-Ti系锌渣有数量增多、团聚长大的趋势,但其尺寸较小,生长较慢,粒径约为30~80μm的Al-Fe-Si系锌渣出现增多现象,生产状态下,部分悬浮渣转变为锅沿面渣、底渣。锌渣相出现的孔洞为锌渣交联生长提供了空间,有助于形成更大的锌渣。
The work aims to investigate the effects of titanium on the formation of suspending dross in continuous hot dip galvanizing aluminum zinc molten bath,and then explore the types,sizes,amounts and growth mechanism of the zinc slags in the molten bath added with Ti.Titanium aluminum zinc alloys were added to the Al-Zn bath to take zinc slag samples from premelting zinc pot and the main zinc pot about 350 mm below the molten bath surface.After addition of Ti,top dross around pot edge and bottom dross were extracted during the replacement of sinking roll.Spark optical emission spectrometer(S-OES)was used to analyze Ti content in the molten bath during different periods before and after addition of Ti.The morphologies,sizes,compositions and amounts of zinc slags were analyzed by scanning electron microscopy(SEM)and energy dispersive spectrometer(EDS).Some Al-V-Ti system zinc slags in ellipsoidal shape with sizes between about 10~43μm occurred in the premelting pot after Ti-Al-Zn alloy was added continuously for about 2 hours.The sizes of 80%zinc slags were about 10~25μm and some holes in different sizes appeared in center of the larger slags.After addition of Ti,suspending dross in main zinc pot Al-Zn bath contained Al-V-Ti system zinc slags of ellipsoidal shape and Al-Fe-Si system zinc slags of polygonal and block shape.The sizes of most Al-Fe-Si system zinc slags were about 10~50μm and much larger than that of Al-V-Ti system zinc slags.After addition of Ti,the top dross around pot edge and the bottom dross were mainly composed of Al-V-Ti system zinc slags in ellipsoidal shape Al-Fe-Si system zinc slags in polygonal shape,and molten solidifying structure.Al-V-Ti system zinc slags with size of 10~46μm were most,accounting for 93%in top dross and 97%in bottom dross.The sizes of 50%of Al-Fe-Si system zinc slags were about 150μm in top dross and 200μm in bottom dross.Ti content in main zinc pot changes more slowly than that in the premelting pot,which basically increases linearly with time.Following the subsequent increase of Ti content in main zinc pot,the Al-V-Ti system zinc slags tend to aggregate in scale and amount.The Al-V-Ti system zinc slags have small sizes and increase slowly.The amount of Al-Fe-Si system zinc slags with size of 30~80μm tend to increase.Under production condition,some suspending dross changes to top dross and bottom dross.Some holes in zinc dross provide space for cross-link growth of zinc slags,which is beneficial to forming larger zinc slags.
作者
王银军
张杰
徐勇
江社明
张启富
WANG Yin-jun;ZHANG Jie;XU Yong;JIANG She-ming;ZHANG Qi-fu(National Engineering Laboratory of Advanced Coating Technology for Metal Materials,Central Iron&Steel Research Institute,Beijing 100081,China;Shanghai Meishan Iron&Steel Co.,Ltd,Nanjing 210039,China)
出处
《表面技术》
EI
CAS
CSCD
北大核心
2020年第1期304-310,325,共8页
Surface Technology
基金
国家重点研发计划课题(2017YFB0304305)~~
关键词
连续热镀
热镀铝锌
铝锌熔池
TI
悬浮渣
锅沿面渣
底渣
continuous hot dip galvanizing
hot dip aluminizing
Al-Zn molten bath
Ti
suspending dross
top dross around pot edge
bottom dross