Estimating elastic modulus using experimental data without strain measurement device and optimization technique of finite element analysis

Various mechanical tests are performed to evaluate mechanical characteristics. Tensile testing is an essential experimental method. Preparing equipment for accurately measuring mechanical properties is challenging because it is very expensive. Hence, tensile tests are performed except for some measuring instruments. The strain-measurement device is often excluded. Therefore, the outcomes of strain measurement methods differ. This study showed the difference in the elastic modulus depending on that in the strain measurement method (strain calculation based on (1) the strain between the grips and (2) that using a strain gauge or other strain measurement devices in the gauge length). Experiments and computational analyses were used to prove the outcome. A novel method to estimate the elastic modulus through a hybrid experimental method and finite element analysis is proposed because the elastic modulus can be lowered when calculating strain based on the deformation amount between grips.