Effects of Stress Triaxiality on Damage Evolution from Pre-Existing Hydrogen Pores in Aluminum Alloy

Abstract

It has recently been reported that aluminum alloy ductile fracture is dominated by micropore growth, whereas the particle fracture mechanism operates incidentally. The effects of stress triaxiality in front of a notch or crack were here investigated by employing microtomography observations. A fractional dimple pattern area originating in micropores increased with the increase in stress triaxiality on fracture surfaces. This implies that the effects of micropores on mechanical properties are more pronounced in notched and cracked materials.

Ductile fracture modeling of metallic materials: a short review

“…In particular, the challenge is represented by formulating the simplest law that includes the main factors governing the void nucleation, growth and coalescence. The extensive experimental campaign conducted in the second half of the last century [52][53][54][55][56][57][58] pointed out the dependency of the damage process on a dimensionless stress parameters: the stress triaxiality  (e.g., [59][60][61][62][63]). In fact, for metallic materials was found that the ductile fracture mechanism and final deformation to fracture (i.e., equivalent strain to fracture  f ) are strongly related to the magnitude of the stress triaxiality (Fig.…”

Construction of Finite Element Meshes for Polycrystal Grains Model from X-ray CT Image

“…Even in X-ray CT, synchrotron radiation CT (SRCT), which is available in a synchrotron radiation facility, achieves the highest spatial resolution. The SRCT permits us to investigate the presence of an inner defect 1) , nucleation of void during deformation 2,3) , crack initiation and propagation [4][5][6][7] , etc., in metallic material because of the penetrating power by high energy and high ux X-ray. It is possible to observe a change process depending on time because X-ray CT inspection is non-destructive.…”