TENSILE TEST APPARATUS FOR MICRO-SCALE SPECIMENS ON SCANNING ELECTRON MICROSCOPE USING SUB-PIXEL DIGITAL IMAGE CORRELATION

摘要

Design parameters for a new micro tensile testing arrangement have been presented. The device is well suited for conducting in-situ tensile test experimentation on the SEM using SPDIC technique to obtain strains and material properties of free-standing thin film specimens. A high precision, high resolution hybrid linear actuator is employed to apply the necessary tensile force. Resolution of linear motion of the actuator is around ±0.3μm. Applied forces are measured using a high precision load cell. The DAQ device is a laboratory computer running a measurement and automation software. Use of the apparatus facilitates real time capturing of images of specimens undergoing strain. Key features of the apparatus are ease of use, portability and simplicity of the entire design while maintaining high accuracy and precision data acquisition capabilities. Coupled with SPDIC techniques, the apparatus can be used to measure in-plane displacements with a resolution up to 10nm.