Development of the Novel Elongation-Measurement Device with In-Plane Bimorph Actuator for the Tensile Test

This paper describes novel elongation-measurement device utilized for uniaxial tensile test. The device consists of two sets of micro probes with piezoresistive sensor for detection of gauge mark position on specimen, and multiple pairs of bimorph actuators for in-plane motion to scan the gauge mark. The voltage from the sensor is put out by the cantilever deflection when the cantilevers climb the gauge marks. By Joule´s heating, movement of the bimorph actuator along one axis was achieved, and detection of gauge mark position was also realized. In the uniaxial tensile test of single-crystal silicon (SCS) film specimen, the mean Young´s modulus of 164.0 GPa was able to be measured by using the device. The measured modulus agreed with that derived from CCD-image analysis. The developed device would be useful for measuring elongation of film specimen during the uniaxial tensile test.