ABSTRACT
This article deals with torsion fatigue tests carried out on the aluminum alloys: AISI 6061-T6 and 6063-T5, under two load ratios: R = −1 and R = 0, both of them at 10 Hz of frequency. The tests were obtained at room temperature (23°C) and with environmental humidity comprised between 35% and 45%. Results reveal a noticeable fatigue endurance reduction on tests with R = 0 against tests at R = −1 for both aluminum alloys. The load ratio was fixed by imposing the initial angle before the testing starting. A new torsion fatigue machine has been developed by two of the authors (under patent consideration before the Mexican Institute of Industrial Property), which has the versatility of torsion tests at different frequencies and load ratios; a general description of this machine is presented in the article. The torsion fatigue life and the fracture surfaces were analyzed for the two aluminum alloys and both torsion fatigue load ratios, leading to drawing up the conclusions related to this research article.
