作　　者： ; ; ;

机构地区： 浙江大学航空航天学院

出　　处： 《机械工程学报》 2008年第11期53-58,共6页

摘　　要： 为了提高热压成型品质,对手动脱模及自动脱模所产生的缺陷进行了分析。采用有限元模拟了高深宽比微结构的脱模过程。模拟结果显示在自动脱模时应力集中主要出现在微结构底部,而最大脱模应力出现在脱模的起始阶段,这时的脱模缺陷主要以颈缩和根部断裂为主。而手动脱模引入的微小脱模方向偏差会造成巨大的应力集中,该应力集中在脱模阶段后期达到最大。5°的脱模方向偏差造成的应力集中可达190 MPa,这时的脱模缺陷主要表现为微结构倾倒及其根部断裂。因而对于高深宽比微结构的热压印成型,必须要采用自动脱模装置。为了克服常规自动脱模装置导致聚合物翘曲变形问题,设计了新型的气动脱模机构并集成到自行设计的热压印装备中。随后的压印试验中采用该气动脱模装置成功制得深宽比约为3.3的微结构,证实了该脱模装置的有效性。 The defects caused by auto/manual demolding are studied to get better imprint quality in micro hot embossing process. Finite element method （FEM） is used to simulate the demolding process of high aspect ratio microstructures. The results show that the stress concentration mainly occurs at the bottom of microstructures when the auto demolding device is used. The maximum demolding stress is generated during the initial stage and the defects are mainly necking and root fracture. Great stress concentration will be caused by concentration little demolding direction deviation in manual demolding, and that stress concentration will reach the maximum in the late stage of the demolding process. 190 MPa stress can be caused due to 5° direction deviation, then the demolding defects are mainly microstracture topping and root fracture. So an auto demolding device is needed when fabricating high aspect ratio structures. A new pneumatic demolding device is designed to overcome the warp distortion of polymer substrate caused by the traditional demolding system. Successful fabricating of microstructures with an aspect ratio of 3.3 verifies the improvement of the demolding device.

关 键 词： 热压 脱模应力 有限元法 聚合物

领　　域： [电子电信]