稀土对盐浴渗钒动力学的影响  

Effect of Rare Earth Elements on Kinetics of Salt Bath Vanadizing

作　　者：陶小克[1] 彭日升[1] 刘杰[1] 

机构地区：[1]天津理工学院材料科学与工程系,天津300191

出　　处：《中国稀土学报》2000年第4期352-355,共4页Journal of the Chinese Society of Rare Earths

基　　金：天津市自然科学基金!资助项目 (9736 0 3711)

摘　　要：在盐浴渗钒中添加稀土对钢表面渗钒有明显的催渗作用 ,渗钒速度约提高 30 %～ 40 %。对 95 0℃经不同时间渗钒的试样测定渗层深度(x)。将x及所对应时间 (t)代入经验公式xn=Kt(lnx =lnK/n +lnt/n) ,经一元线性回归处理可知 ,x与t之间满足x2 =Kt抛物线关系。添加稀土可以加快渗剂反应而增大渗剂钒势。稀土的强还原性使钢件表面的氧化物还原而活化其表面。稀土渗入钢基体和VC渗层 ,会增大晶体缺陷密度 ,使碳原子扩散易于进行。稀土的添加可降低碳原子的扩散激活能 ,起到催渗的效果。Adding rare earths into permeating agent has an obvious catalytic effect on vanadizing on steel surface, and the vanadizing rate can increase by about 30%～40%. The case depth ( x ) of the samples which has undergone different periods of vanadizing time at 950 ℃ was measured. These depth values ( x ) and its corresponded time ( t ) were substituded into the experience formula, x n=Kt (ln x=(1/n) ln K+(1/n) ln t ), and were processed by mono linear regression. It is found that x and t have the relationship of x 2=Kt . Addition of rare earth can promote reaction of the permeating agent, and therefore increase vanadium potential of the agent. Rare earths, as a strong reductant, makes the oxide on the steel surface reduce, and thus activates the steel surface. Permeating of rare earths into steel and the VC layer increase the crystal fault density, and, together with its excellent chemical activation, makes carbon atoms diffuse easily. These functions of rare earth can decrease the diffusion activation energy of the carbon atoms, and therefore has catalytic effect on permeation.

关 键 词：稀土 盐浴渗钒 扩散激活能 钢 表面处理 

分 类 号：TG174.445[金属学及工艺—金属表面处理]