作　　者： ; ; ;

机构地区： 浙江大学机械工程学系

出　　处： 《传感技术学报》 2006年第05B期2011-2014,共4页

摘　　要： 激光直写聚合物微流道是非常有效的加工方法,但是,由于激光烧蚀聚合物的热流密度很高,在小的热影响区产生过大的集中热应力,热应力导致产生微裂纹,降低材料的强度和疲劳寿命,严重的引起材料破坏性失效.为了预测激光烧蚀时的热应力大小随时间空间的变化规律,根据烧蚀模型推出了三维弹性热应力模型.首先由烧蚀模型预测温度场分布和烧蚀流道外形,根据流道轮廓和温度场计算弹性热应力场与烧蚀过程的关系.分析结果表明弹性热应力位于低于或平行于烧蚀表面的一定厚度层内,这也许是引起表面微裂纹的原因. Lasers are emerging as a valuable tool for direct-writing polymer micro channels. Unfortunately, the large, concentrated heat flux rates that allow the laser to efficiently ablation polymer also result in large localized thermal stresses in a small heat-affected zone. then thermal stresses can lead to microcracks, a decrease in strength and fatigue life, and possibly catastrophic failure. In order to predict where, when, and what stresses occur during laser grooving, a three-dimensional elastic stress model has been integrated into ablation solution. First, the solution predicts the temporal temperature fields and there erosion surface. Then, using the grooved geometry and temperature field, the elastic stress fields are calculated as they develop and decay during the laser ablation process. The results of the analysis show elastic thermal stresses develop over a thick layer below and parallel to the surface, which may be the cause of subsurface cracks.

关 键 词： 激光加工 热应力 直写加工 烧蚀算法

领　　域： [电子电信] [动力工程及工程热物理] [动力工程及工程热物理]