摘要
硅锰熔渣具有高温显热,且SiO_(2)和Al_(2)O_(3)的质量分数之和大于50%,其物理化学特性与岩浆形成的天然石材具有相似性。采用硅锰熔渣制备铸石材料时,制备过程产生的内应力易导致石材开裂。本研究采用差示扫描量热法(DSC)、X射线衍射仪(XRD)、扫描电子显微镜(SEM)及热膨胀测试等手段,系统研究了晶化温度对硅锰渣铸石的物相组成及热膨胀性能的影响。结果表明,以92%硅锰渣为主要原料,以2%蛇纹石矿和6%铬铁矿为改质剂,分别在900、1000、1050℃晶化温度下保温并经700°C退火处理后,所得硅锰渣铸石性能符合《天然花岗石建筑板材》(GB/T 18601—2009)标准要求;硅锰渣铸石的析晶温度区间为900~1100°C,主晶相为辉石和黄长石;900°C晶化时优先析出辉石,随着晶化温度升高,黄长石开始在非晶相中析出,并与辉石晶粒共同长大,组织结构趋于致密;900°C制备的硅锰渣铸石因含有较多的非晶体,在1050~1100℃时发生晶相转变,在残余玻璃相中生成黄长石,析晶放热导致硅锰渣铸石的膨胀系数增大。1050、1000°C下制备的硅锰渣铸石晶体结构更致密,热膨胀系数更大,并且温度越高,热膨胀系数越大。
Silicon-manganese slag possesses high-temperature sensible heat,with the mass fraction sum of SiO_(2)and Al_(2)O_(3)exceeding 50%,endowing it with physicochemical properties similar to those of magmatic natural stone.However,the internal stress generated during the preparation of cast stone from silicon-manganese slag often leads to material cracking.In this study,the effects of crystallization temperature on the phase composition and thermal expansion properties of silicon-manganese slag cast stone were systematically investigated using differential scanning calorimetry(DSC),X-ray diffraction(XRD),scanning electron microscopy(SEM),and thermal expansion testing.The results indicated that the silicon-manganese slag cast stone,prepared with 92%silicon-manganese slag as the main raw material and 2%serpentine and 6%chromite as modifiers,and subjected to heat treatment at crystallization temperatures of 900,1000 and 1050℃followed by annealing at 700℃,met the requirements of the Natural Granite Building Slabs(GB/T 18601—2009)standard.The crystallization range of the silicon-manganese slag cast stone was determined to be 900-1100℃,with pyroxene and melilite as the primary crystalline phases.During crystallization at 900℃,pyroxene was preferentially precipitated.As the crystallization temperature increased,melilite began to precipitate within the amorphous phase,and both crystalline phases grew in size,resulting in a denser microstructure.The cast stone prepared at 900℃,containing a higher proportion of amorphous phase,underwent a phase transition at 1050-1100℃,where melilite was generated in the residual glass phase.The heat released during crystallization caused an increase in the thermal expansion coefficient of the silicon-manganese slag cast stone.The cast stones prepared at 1050 and 1000℃exhibited denser crystal structures and higher thermal expansion coefficients,with the thermal expansion coefficient increasing as the preparation temperature rose.
作者
周志勇
黄燚
程昭阳
李宇
张延玲
ZHOU Zhiyong;HUANG Yi;CHENG Zhaoyang;LI Yu;ZHANG Yanling(State Key Laboratory of Advanced Metallurgy,University of Science and Technology Beijing,Beijing 100083,China)
出处
《江西冶金》
2026年第1期55-62,共8页
Jiangxi Metallurgy
基金
乌兰察布市“揭榜挂帅”项目(2022JB002)。
关键词
硅锰渣
铸石
晶化温度
热膨胀系数
析晶
silicon-manganese slag
cast stone
crystallization temperature
thermal expansion coefficient
crystallization
