High cycle fatigue behavior of Al1070 alloy severely deformed by equal channel angular pressing process

Abstract

In the present work, equal channel angular pressing of commercial pure aluminum 1070 was performed up to 4 passes using route Bc. For equal channel angular pressing operation, a suitable die set was designed and manufactured. X-ray diffraction analysis was used to determine the microstructure of the equal channel angular pressing-ed material. The fracture surface morphology and microstructure after fatigue were investigated by scanning electron microscopy. Mechanical properties of the equal channel angular pressing-ed material were evaluated by hardness and tension tests. Also, cyclic deformation behavior of severe plastic deformation Al1070 has been studied and results show a significant variation in hardness, ultimate strength and fatigue properties in high cycle fatigue life. Coefficient of fatigue strength σ′f and Bridgman correction factor have been obtained by S-N curve and tension test specimens, respectively, and compared before and after equal channel angular pressing process. Also an useful relation has been derived between fatigue life ( Nf) and stress amplitude ( σa) in high cycle fatigue region. Results indicated that there was not clear relation between fatigue strength coefficient and true corrected fracture stress in this case.

The processing route towards outstanding performance of the severely deformed Al–Mg–Mn-Sc-Zr alloy

“…The increase of the Basqiun exponent after deformation processing, including SPD, has been frequently reported in the literature, e.g. [58][59][60], and this is associated with the strengthening effect, which tends to increase the susceptibility of the material to the internal imperfections inherited from SPD as well as to cyclically induced damage. Thus, compared to the as-cast state, the deformation processing increases the fatigue strength coefficient A in parallel with the microstructure refinement and the increasing monotonic strength.…”

Microstructural evolution and mechanical behaviors of equal channel angular pressed copper

“…The base of the equal channel angular pressing (ECAP) is an extrusion process that is a severe plastic deformation technique. Recently, it has been demonstrated that ECAP can be used to produce bulk ultra-fine grained metals and alloys 10 that provides a potential for obtaining high strength 11 and enhanced superplasticity properties. 12–15 With suitable mechanical properties and without discontinuity or porosity, ultra-fine grained materials obtained by ECAP have drawn significant interests from researchers during the recent two decades.…”