Aperfeiçoamento de um esclerômetro pendular: projeto e execução

Abstract

Selection of materials resistant to abrasive wear requires tests that represent actual conditions of application and use. This fact led to the development of the pendulum sclerometry technique, which makes it possible to quantify the scratch hardness and the specific scratch energy of different materials. In order to develop this technique, a simpler sort of equipment was used as a basis, the components of interest were proposed and designed, the electrical components were installed, adaptations were made for the experimental performance, the equipment was validated through tests with scratching of SAE 1080 steel, glass and polycarbonate samples, and the data for the scratching specific energy were collected. The proposed and developed equipment proved capable of obtaining the data of the scratching energy of the materials to be analyzed, in a systematic way, with reduction of the time of the tests in comparison with the original equipment, ease of execution of the experimental methodology, use of only one sample and use of different geometries of samples and indenters. The results of using the equipment without scratching – regarding losses from various dissipations – suggested a high repeatability, with a standard deviation of 0.027 J and a coefficient of variation of 0.15, providing a good quality of response of the equipment. The improved and modified equipment was considered validated, since it was able to calculate the values of the volume removed by the scratching, obtained a value of the specific energy of the materials that was similar to what was predicted in the consulted literature, and provided results of low experimental variability.