V5+及Cr3+掺杂对C2S多晶型的影响机制

摘要

在水泥生料中分别掺入质量分数为0.5％、1.0％、1.5％、2.0％和3.0％的V2O5和Cr2O3,煅烧至1550℃,研究V5+和Cr3+掺杂对C2S多晶型形成过程的影响.经化学分析、X射线衍射(XRD)、扫描电镜(SEM)和红外光谱(ET -IR)等方法分析,结果表明:当V2O5和Cr2O3质量分数分别大于0.5％和1.5％时,稳定β- C2S效应逐步明显,且高掺量V2O5能促使α - C2S形成;Cr2O3掺杂使w(f-CaO)呈递增变化,而V2O5掺杂使w(f- CaO)呈先增大后减小趋势变化;高温热特性及形貌分析证明:V5+和Cr3+易富集在β - C2S晶界或位错上,阻碍γ-C2S的形成,同时约束β- C2S的晶粒尺寸.%The effect of doped V5* and Cr3+ on the formation of C-2S was studied,including sample with nothing added in and some samples which were added with foreign oxides V2O5,Cr2O3 respectively by 0.5% ,1% ,2% and 3% ,all calcined at 1550℃. By means of chemical analysis,XRD,SEM and infrared specboscopy analysis,the effect mechanism of V5+ and Cr3+ was discussed. The results can be get;both V2O5 and Cr2O3 can stabilize β-C2S obviously,when the adding content exceeds 0. 5% and 1.5% respectively,and high content of V2O5 can cause α-C2S to form; when Cr2O3 doped,the content of f-CaO keeps increasing if the content adds,but when V2O; doped, the content of f-CaO increased firstly and then decreased. Combining high temperature-chemical properties of V2O3 ,Cr2O3 with their SEM analysis,it is shown that V5+ and Cr3+ are easily concentrated in crystal boundary and line defect of β-C2S,which hinders the formation of γ-C2S and restrains the grain size of γ-C2S.