Improvement of a pendular scratching tester: Design and Execution
Scratching tester, scratchhing hardness, specific removal energy, arduino.
Many new techniques are being developed to obtain results similar to conventional and normative tests, with an increase in favor of the reduction of experiment time, cost reduction and ease of obtaining specimens. This work aims to design, develop and validate a pendular rebound hammer, capable of enabling the study of the behavior of scratch energy in metallic materials. Therefore, the necessary adaptations, the assembly of circuits and electronic components, the elaboration and dimensioning of the specimen, such as movements of components, and electronic components, are eliminated as steps related to the development of the equipment's fuselage. In the preliminary phase of the project, the existing fuselage, the pendulum, the main axle and a system were considered, for subsequent adaptations and internal construction. Then, the design and execution of a new system was carried out, which allows the movement of samples in three, the recovery of the sample to carry out the tests and the electronic control of the vertical displacement of the sample. Regarding the development of the pendulum measurement system, first a mechanism was developed to determine the depth of scratch of the penetrator in the sample, then the pendulum release mechanism through a magnetic triggler, then the pendulum angulation and height calculations in movement, and finally the scratch energy was calculated. To ensure that the sample was not scratched at an inappropriate time, a servo motor was placed to remove the sample holder from the risk region. This done, the electronic connections associated with each component were made, and a data processing center was also built, using an Arduino AtMega2560 and a LCD. The developed equipment was submitted to validation tests, where its perfect functioning is verified. The enhanced version allows for quick test execution, the use of easily fabricated specimens, the performance of multiple scratch tests with the same specimen, the vertical, lateral and horizontal displacement of the sample, the control of scratch depth, and the calculation of scratch energy, being displayed on the LCD screen.