KBr晶体的生长及加工工艺研究

Study on the growth and processing technology of KBr crystal

采用电阻加热Czochralski法和一控双变技术,在最佳工艺参数(转速:6 r/min~8 r/min;拉速:1 mm/h~2 mm/h;循环水温度:28℃±1℃;降温速率:8℃/h~10℃/h;轴向温度梯度:1℃/mm~2℃/mm)条件下,生长出了Φ96 mm×30 mm的KBr晶体.分析了晶体的潮解机理,采用饱和溶液对KBr晶体进行抛光,分析抛光压力、抛光盘转速、抛光液流量和抛光时间对晶体表面去除率和粗糙度的影响,得到最佳的抛光参数:最佳压力为0.1042 MPa、抛光液流量为15 mL/min、抛光盘转速为30 r/min和抛光时间为20 min.对抛光后的晶体元件透过性能测试表明,厚度为4 mm晶体的透过率为90.2%,在透过波段存在一定吸收.

Under the best process parameters(rotating speed:6 r/min~8 r/min,pulling speed:1 mm/h~2 mm/h,circulating water temperature:28℃±1℃,cooling rate:8℃/h~10℃/h,axial temperature gradient:1℃/mm~2℃/mm),a high-quality KBr crystal ofΦ96 mm×30 mm was grown by using resistance heating Czochralski method and one-control double-variation technology.The deliquescent mechanism of the crystal was analyzed,and the KBr crystal was polished with‘water+ethanol+surfactant’.The effects of polishing pressure,polishing disk speed,polishing fluid flow rate and polishing time on the removal rate and roughness of the crystal surface are analyzed,and the best polishing parameters are obtained:the optimal pressure is 0.1042 MPa,and the polishing fluid flow rate is 15 ml/min,the rotating speed of the polishing disc is 30 r/min and the polishing time is 20 min.The performance test of the polished crystal element shows that the transmittance of the crystal with a thickness of 4 mm is 90.2%,and there is some absorption in the transmission band.