Fracture characteristics of a particulate-reinforced metal matrix composite

Damage mechanisms at room and high temperature in notched specimens of Al6061/Al2O3 particulate composites

“…This fact could seem not in agreement with previous indirect measurements of microstructural damage by acoustic emission [15] and potential drop [24] techniques on the same materials, revealing that particle fracture occurred in the early stages of plastic deformation and that it accumulated with plastic strain more easily in the highly reinforced composite. Nevertheless, the higher propensity to fracture at low strain of the fraction of large ceramic reinforcement particles in Al6061/Al2O3/20p (explained in literature [16,19,25] as due to local costraint caused by different stiffness of matrix and particles) and the larger strain accumulated at fracture by Al6061/Al 2 O 3 /10p, having more homogeneous population of smaller alumina particles , can account for all these experimental results. 9 Even if particle fracture is not the only form of material damage, the observations on specimens from tests interrupted at maximum load indicated that it occurred before debonding become evident.…”

“…On the other hand, in an experimental study Liu and Lewandowsly [17] observe d that when a compressive hydrostatic stress was superimposed during tensile tests of on Al6061/Al 2 O 3 particulate composite, it did not suppress particle fracture but only the void growth within the matrix from cracked particles. The effect of stress triaxiality on the microstructural damage of an Al6061/Al 2 O 3 /20p particulate composite was observed on fracture toughness specimens by Hadianfard et al [16]. They suggested that in the region ahead the crack tip particle fracture was the dominant damage form of microstructural damage.…”

“…The effect of multiaxial loading condition on damage characteristics at room and high temperature will be the topic of the present paper, where triaxiality induced by specimen geometry will be examined. To the authors' knowledge, t he effect of the presence of a multiaxial state of stress was investigated in some literature studies , by comparing the surface and inner regions of cracked toughness test specimen [16]. In other cases specific tests were developed, superimposing hydrostatic compression state on pulled uniaxial tensile specimens [18][19], or performing tensile tests on notched specimens [10][11][12][13][14][15][16][17][18][19][20][21].…”

Effect of overaging and particle size on tensile deformation and fracture of particle-reinforced aluminum matrix composites

“…Larger particles fail prior to smaller particles, nucleating voids in the matrix. [29] a function of distance from the fracture surface ( Figure 6). While there was still no significant difference in the extent Because of the presence of rigid particles, the matrix is under a tensile triaxial state of stress and is unable to relax strain of particle fracture, particularly with respect to aging treatment, the magnitude of particle fracture was significantly by plastic deformation.…”

Study on fracture behavior of particulate reinforced magnesium matrix composite using in situ SEM

“…And extensive researches have been performed on the fracture behavior of discontinuously reinforced metal matrix composites (DRMMCs) using the in situ SEM technique [7][8][9][10][11][12][13]. The failure process of DRMMCs can be conveniently split into three stages: nucleation, growth and coalescence of microcracks [7][8][9][10][11][12][13][14][15][16].…”