Development Of Advanced Blister Instrument And The Research Of Mechanical Properties Of Films Under Thermo-mechanical Loadings

In recent years,with the rapid development of microwave electronics,microelectronics technology and electronic packaging technology,thin film materials have been widely used in lots of hi-tech and traditional industrial areas.In the process of practical work,thin film materials often service in the complex environments.However,in terms of the current situation,academic and engineering circles lack in-depth study of complex load deformation damage and failure mechanism of the thin film materials,which affects the service performance evaluation and life prediction of materials.In addition,the high or low temperature,electric field,magnetic field and other special physical fields also affects the performance of materials.Under the environment of high temperature,the mechanical behavior of thin film materials will change significantly.Therefore,developing the material mechanical properties testing technology under the condition of complex load is necessary.According to the work environment of thin film materials,a thermal load automatic control system is developed.Basis on the original bulge setup,a new multifunctional bulge test platform with coupled thermo mechanical loadings is designed.It provided convenience for the characterizations of thin film material mechanics performance which served in complex working conditions.The results of the study is very significant which provides reliable proof for membrane element stress analysis,failure analysis and life prediction.The specific work content is as follows:(1)There are lots of methods to test mechanical properties of thin films,while difference is mainly manifested on the methods of loading and measurements.In this paper,we first analyze and compared some measuring instruments such as stretching,blister and indentation instruments,then study the heating part of various test devices.At last,a heating environment box which produce a uniform temperature field is designed.(2)The blister test theoretical model under thermo-mechanical loadings is deduced.According to the stress tensor and the increment of the temperature,combined with the traditional blister test model,the deduction of the blister test equation under thermo-mechanical loadings is carried out in different deformation stages.(3)Based on the self-developed bulge experiment equipment,the mechanical properties of two common metal,include nickel film and PI film,are researched by experiment and theory analysis.We obtain the the elastic modulus of the films at different tempurture and analyze the changing of their elastic modulus with temperature.The experimental results showthat the elastic modulus of the films is changing with different working temperatures.