Influence of anisotropic distribution of whiskers on the superplastic behavior of aluminum in a back-extruded 6061 Al-20% SiCW composite

Texture and microstructural changes after thermal cycling of 6061Al-20vol%SiCw metal matrix composite: The role of microscopic internal stresses

“…1E), were 152.5 mm in diameter with 12.7 mm wall thickness. Details of the tensile sample dimensions and the thermal cycling tests are described in [15]. Tests were conducted on samples machined with the tensile axis direction parallel to the extrusion, E, and transverse, T, directions, consistently with the reference system sketched in Fig.…”

“…1E). Thermal cycling tests were carried out under controlled constant stress conditions, while the temperature oscillated in the interval of 100-450 • C in a period time of 200 s [15]. For the present study, a longitudinal sample tested at 10 MPa and a transverse one tested at 7 MPa were selected for microstructural characterization.…”

“…In addition, they may also experience very large deformations, exceeding 1000% tensile elongation: i.e., superplasticity is achieved [14][15][16]. This kind of superplasticity is usually referred to as internal stress superplasticity [15][16][17], ISS.…”

“…In addition, they may also experience very large deformations, exceeding 1000% tensile elongation: i.e., superplasticity is achieved [14][15][16]. This kind of superplasticity is usually referred to as internal stress superplasticity [15][16][17], ISS. It differs from the as known "structural superplasticity" (which occurs under isothermal conditions), where grain boundary sliding, GBS, is well accepted to be the dominant deformation mechanism [17][18][19].…”

Texture evolution with superplastic deformation of a AlCu4Mg/Si3N4/20p composite

“…Repeated temperature changes (cycles),hence, provoke extensive plastic deformation under the action of a small applied tensile stress and a superplastic response can be obtained in the composite [10]. Usually, viscous plastic flow, with the stress exponent n equal to 1 (Newtonian flow) in the power law creep equation (where…”