Desenvolvimento de programa computacional para determinar a vida útil e dimensionar eixos mecânicos considerando formulações analíticas e concentradores de tensão do tipo adoçamento

Abstract

In the development of mechanical projects, it is very important that components are not oversized to the point of becoming unnecessarily expensive and heavy. However, the designed component needs to have mechanical strength. In the area of mechanical design, the calculation of the maximum allowable stress is of great importance, since if there is a structural failure in the design, there is a great possibility of failure in this region. However, in most mechanical engineering projects, the use of purely static loads is insufficient, in several types of problems, it is necessary to consider transient loads, typical cases of mechanical fatigue. Analytical formulations can be used for fatigue calculations, but using such formulations manually takes a considerable amount of time, and there is a risk of being influenced by human error in the process. In projects considering fatigue, it is of fundamental importance to automate the calculation process. In this project, a computer program was developed with a graphic interface in MATLAB language, to automate the dimensioning, the calculation of the maximum stress under static loads, calculation of the useful life in projects of mechanical axes under fatigue stresses. The methodology of the project is to consider a mechanical axis with a shoulder type stress concentrator, which is under alternating or static loads of bending, torsion and traction, in a combined or isolated way, with the load varying in time in a cyclical way, with and without the presence of stress concentrator. Using the DE-Goodman, DE Gerber, DE-ASMI Elliptical and DE-Soderberg methods to generate a comparative study between the methods for a better design choice. Generating the MechCal program and its three versions, MechCal – Shaft Stress, MechCal – Shaft Fatigue and MechCal – Shaft Design, for calculating the maximum stress, useful life and shaft design, respectively.