Wyniki wyszukiwania - BazTech

Ograniczanie wyników

1 Advances in Science and Technology. Research Journal

1 2025

Powiadomienia systemowe

Sesja wygasła!

Znaleziono wyników: 1

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: torsion surface

Sortuj według:

Ogranicz wyniki do:

The influence of the load level during cyclic torsion on the fatigue life and fracture surface of tin-zinc-lead bronze RG7

Małecka Joanna, Żak Krzysztof, Łagoda Tadeusz

Advances in Science and Technology. Research Journal

2025

Vol. 19, no. 8

395--412

The study analysed samples made of tin-zinc-lead bronze RG7 after fatigue tests under cyclic torsion conditions. The behaviour of the material used in both mechanical and building structures was analysed. Samples made for various load levels were subjected to this analysis. Fatigue cracks during cyclic torsion of samples made of RG7 bronze were analysed for nine load levels. Fatigue crack surfaces were analysed, with particular emphasis on the crack direction. For lower loads, the macroscopic fatigue crack surface is inclined at an average angle of 40°. The angle of the inclined plane of the cyclic torsion crack tends to decrease with increasing stress amplitude. The less load the tested samples carry, the more uniform the appearance of the crack surface. In the case of samples tested at lower stresses, a crack zone was observed in the lower part of the crack, which was damaged in the final phase of the test. This part of the crack was characterised by a rougher surface, where the tearing of material grains could be observed. The 3D surface analysis showed that a large fractal dimension was obtained for the stress amplitude τan in the range of higher loads, indicating the surface's high complexity. Analysing the isotropy of the surface using the Str parameter and assessing the percentage level of isotropy, it can be concluded that the obtained surfaces have a periodic anisotropic character, which proves that a structure subjected to high stresses has a directed and dominant direction of cracking.