Study on Measurement Method of Material Elastic Index

Abstract

Elastic index is the required important parameters in the theoretical analysis and design calculation of components. Mechanical testing method and electrical measuring method are commonly used in mechanics experimental. This article discusses the ultrasonic method which is used to measure the material elastic index. In this paper, Using ultrasound method to measure the elastic index of 1095 steel, and comparing with literature values, ultrasound measurement method and electrical measurement method are used to measure modulus of elasticity of Mullite ceramic. Experimental results show that the ultrasonic measured elasticity coefficient value is very similar with literature value; Comparing the two groups of experimental data,it is found that data obtained by ultrasound measurement method is compact while data obtained by electrical measurement method is dispersed and the average value of two groups variate within 5%. This method has benefits such as no use of strain gauge,low costs, short cycle and multi-point measurement, thus it is suitable for multi-person experiment. In addition, this method can broaden students’ knowledge horizon and cultivate independent thinking ability and practical ability. Introduction Elasticity indicators Including the young's modulus of elasticity, poisson's ratio, shear modulus of elasticity are the important need parameters in process of theoretical analysis and design calculation. In the present course of engineering mechanics, the elastic index of the material is mainly determined by mechanical testing method or electrical measuring method[1,2]. But mechanical testing method is big costs due to use a specimen for measure once. Electrical measuring method requires students to accept training and test cycle is long, so the demand to the student ability is high. In this paper, ultrasonic method was used to measure the material elastic index. The method by measuring the density of material, the material of transverse wave and longitudinal wave propagation velocity, is used to calculate the material elastic performance indicators such as shear modulus, young's modulus of elasticity and poisson's ratio, etc. This method broadens students’ knowledge horizon and improves students’ experiment analytical abilities, being suited for promotion in college mechanical curriculum with fewer classes and more students participate in experiments.