Determination of the elasticity module in steels and aluminum through the natural frequency compared to the tension test

Abstract

Many materials, when in service, are subjected to forces or loads. In these situations it is necessary to know the material properties, among them the elasticity modulus, to design parts and devices, so that any resulting deformation is predictable and not enough to occur plastic deformations, accelerated fatigue or even fracture. In this paper a dynamic method was used to define the elasticity modulus of an aluminum alloy and two types of steel measuring the natural frequency of vibration without the need to destroy the specimen, as in tensile tests for example. The experimental procedure consisted of subjecting the material to controlled impacts to obtain the natural frequencies through an accelerometer. With the frequency results, by mathematical means proposed by ASTM E 1876, the material’s elasticity modulus can be defined. This procedure can identify the material’s elasticity modulus in a non-destructive, fast and reliable manner. With the intention of obtaining parameters that can generate a level of reliability in the tests, the results of this experiment were compared with the results obtained in the tensile test, where the difference of Domex 700 steel between the methods was 3.22%, SAE 1522 steel difference was 1.68% and the 1200H14 aluminum alloy difference was 6.27%, showing that the method is valid and the results were similar.