超弹性样品中形变应变场检测方案(其它无损检测仪器/设备)

智能文字提取功能测试中

The aim of this research was to develop and test an experimental method,which could be scaled to samples of 4 mm x 4 mm x 1-2 mm in size. Tovalidate the design of the experimental method, it was applied to samples(10 mm by 10 mm by 2.5 mm in size) of a soft hyperelastic silicone-rubberusing available equipment.The biggest challenge in this research was the small scale at which testingwas performed. In addition, the size of force measurements was small (under10 N), which meant that force measurements inherently included noise, whichcould not be neglected.The method was designed such that stress concentrations were avoided andboundary conditions were simple enough to be easily implemented in a finiteelement analysis. A uni-axial compression test was performed where full-fielddisplacement data was measured using digital image correlation and force datawas measured using a 50 N load cell. Displacement and force results for compressionsof between 20-55 % of the height of the sample were used in aninverse finite element model updating method to iteratively determine a threeparameter Mooney-Rivlin material model for the hyperelastic silicone-rubber.There was a large amount of variability in the force results, even though thedisplacement inputs for the tests were repeatable. The inverse finite elementmodel updating method showed repeatability in the value to which it converged,however the material model obtained from the optimization processproduced accurate displacements neither when plotted against the experimentaldisplacements nor when implemented in a validation test geometry.