晶体硅金刚线切割废料氮化反应的研究

为了综合利用晶体硅金刚线切割废料,以其为原料,使用卧式氮化炉进行氮化反应,研究了氮化温度(1300、1350、1400、1450和1500℃)、氮化保温时间(1、1.5、2、2.5和3h)以及α-Si3N4外加量(外加质量分数分别为0、5%、10%、15%和20%)对氮化反应的影响。结果表明:在一定范围内,氮化温度的升高有利于α-Si3N4、β-Si3N4和Si2N2O三种物相的生成;氮化时间的延长有利于α-Si3N4、β-Si3N4和Si2N2O三种物相的生成,但氮化时间过长会导致α-Si3N4转变为β-Si3N4,以及Si2N2O转化为Si3N4;以α-Si3N4为添加剂,有利于α-Si3N4的生成以及氮化反应的进行。综合考虑切割废料的氮化程度,较优氮化条件为1400℃保温3h,α-Si3N4添加剂外加量10%(w)。

Nitridation reaction of crystal silicon diamond wire cutting wastes

In order to make comprehensive use of wastes,the crystal silicon diamond wire cutting wastes were nitridized in a horizontal nitriding furnace.Effects of the nitriding temperature (1 300,1 350,1 400,1 450 and 1 500 ℃),the nitriding time (1,1.5,2,2.5 and 3 h) and α-Si 3N 4 addition (0,5%,10%,15% and 20%,by mass) on the nitriding reaction were researched.The results show that the increase of nitriding temperature and the prolonging of nitriding time are beneficial to the formation of α-Si 3N 4,β-Si 3N 4 and Si 2N 2O in a certain range,but a too long nitriding time will lead to the transformation of α-Si 3N 4 to β-Si 3N 4 and Si 2N 2O to Si 3N 4.Using Si 3N 4 as the additive is beneficial to the formation of α- Si 3N 4 and nitriding reaction.Considering the nitriding degree of cutting wastes,the optimum nitriding conditions are as follows:holding at 1 400 ℃ for 3 h,and 10 mass % of Si 3N 4 addition.