CAJ | 학술논문

CO2激光局域辐照对熔石英损伤特性的影响*
CO2격광국역복조대용석영손상특성적영향*
The influence of CO2 laser local irradiation on the laser damage resistance of fused silica?

万方数据

物理学报物理學報 물이학보

2013年 9期 330-335 ,共6页

刘春明%杨亮%晏中华%蒋勇%王海军%廖威%向霞%贺少勃%吕海兵%袁晓东*%郑万国%祖小涛

류춘명%양량%안중화%장용%왕해군%료위%향하%하소발%려해병%원효동*%정만국%조소도

CO2激光局域辐照%熔石英%损伤特性 CO2激光跼域輻照%鎔石英%損傷特性
CO2격광국역복조%용석영%손상특성
CO2 laser local irradiation%fused silica%laser damage resistance

研究了CO2激光局域辐照对熔石英损伤特性的影响,发现当辐照中心温度较低时(1139 K),辐照对损伤阈值没有明显影响,但辐照中心温度较高时(1638 K),辐照对损伤阈值有明显的影响,损伤阈值随距离辐照中心间距的增大而减小,在残余应力产生光程差最大处附近,损伤阈值降到最小,随着与辐照中心间距的进一步增加,损伤阈值略有上升.对导致此现象的原因做了分析.由于残余应力的存在,在辐照中心发生再损伤产生的裂纹后,裂纹先沿径向扩展,在残余应力产生光程差最大处附近,裂纹转而向切向扩展,这可能与径向和环向张应力随半径的变化有关.在采用热处理炉退火消除残余应力时,必须注意元件的洁净处理,否则退火会出现析晶现象,对损伤阈值和透射率造成不良影响.
연구료CO2격광국역복조대용석영손상특성적영향,발현당복조중심온도교저시(1139 K),복조대손상역치몰유명현영향,단복조중심온도교고시(1638 K),복조대손상역치유명현적영향,손상역치수거리복조중심간거적증대이감소,재잔여응력산생광정차최대처부근,손상역치강도최소,수착여복조중심간거적진일보증가,손상역치략유상승.대도치차현상적원인주료분석.유우잔여응력적존재,재복조중심발생재손상산생적렬문후,렬문선연경향확전,재잔여응력산생광정차최대처부근,렬문전이향절향확전,저가능여경향화배향장응력수반경적변화유관.재채용열처리로퇴화소제잔여응력시,필수주의원건적길정처리,부칙퇴화회출현석정현상,대손상역치화투사솔조성불량영향.
The influence of CO2 laser local irradiation (CLLI) on the laser damage resistance of fused silica was studied. It is found that CLLI has no evident effect on the laser-induced damage threshold (LIDT) of fused silica when the temperature of irradiation center is low (1139 K). However, the influence of CLLI on LIDT becomes important when the temperature of irradiation center is higher (1638 K). AT first, LIDT decreases with r increasing from zero to rM, where r is the distance to irradiation center, and rM is the distance at which the residual stress-induced phase retardance reaches the maximum. Then, LIDT increases a little when r is larger than rM. The origin of this phenomenon is discussed. Due to the residual stress, re-initiated damage in irradiation region can result in the formation of fractures. The fractures due to the re-initiated damage at irradiation center transport along radial direction firstly, and then transport along the tangential direction near rM. This may be due to the maximum tensile hoop stress and radial stress dependence of radius. Cares should be taken for the optical cleaning when thermal oven annealing is used to eliminate the residual stress. Otherwise, crystallization can be induced by contamination during annealing. The contamination also has negative impact on the light transmission and LIDT.