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, since they are usually associated with several creep mechanisms such as grain boundary sliding, dislocation viscous glide and dislocation climb[12]. The best linear fits of the experimental data...]) and lattice self-diffusion for pure magnesium (135 kJ/mol[14]). Thus, it can be suggested that dislocation creep is the controlled creep mechanism of the as-cast Mg-5Zn-2.5Er alloy at the high steady-stage......
that the dislocation climb controlled creep is the dominant creep mechanism and it is not affected by the semi solid processing and further addition of Mg. Mg improves the alloy creep properties probably...; dislocation climb controlled creep 1 Introduction Among the Al based casting alloys, Al-Si-Mg alloys are the most widely used alloys in aerospace and automotive industries because of the good casting......
to the self-diffusion energy as long as the deformation mechanism is controlled by the glide and climb of dislocations [12]. Moreover, Eq. (2) is also well known for thermal creep equation [1-6]. Usually, Eq... that the rate controlling mechanism for V-5Cr-5Ti alloy compressed in ranges of 1373-1673 K and 0.001-1.0 s-1 is the dislocation climb by overcoming of forest dislocations. Key words: V-5Cr-5Ti alloy; hot......
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. The calculated value of stress exponent, n=6.3, suggests that the compressive creep behavior of the ageing-treated Mg-5%Sn alloy is controlled by dislocation creep at the temperature of 473 K... is controlled by dislocation climb. LIM et al[13] reported that the secondary solidification phase in Mg-MM alloy changes dramatically with the addition of Sn, and the small rod-shaped phase forms in the Mg......
MPa were described[10]. It was suggested that, steady state creep in this alloy is controlled by the cross slip and climb of basal dislocations and with non-basal slip. Power-lowcreep behavior.... The results show that the dominant creep mechanism in this alloy is dislocation creep with minor contribution of the grain boundary sliding. Creep failure took place by the nucleation, growth and coalescence......
is that it keeps a high volume fraction of γ′ phase. Keyword: single crystal nickel base superalloys; alloying elements; creep resistance; dislocation climb... studied by measuring the creep curves and internal stress of dislocation motion, and by EDAX composition analysis as well. It is shown that the size and volume fraction of the γ′ phase in alloy containing......
of theses dislocations are parallel to the cube edges of γ′ precipitates, suggesting that the creep deformation is mainly accomplished by dislocation climb [25, 26]. Further observations... stress of 370 MPa 3.2 Deformed microstructures Figure 6 shows the typical dislocation microstructures of M4706 after different heat treatments and creep deformation at 870 °C and 370 MPa. Although......
/mol, respectively. These values indicate the dominant creep mechanisms for the alloy under the present test conditions. The stress exponent n=4-6 is for dislocation climb controlled creep[14... containing Ca and Sr have larger activation energies than the AT42 alloy. The values of both parameters fit the values for dislocation climb controlled creep, suggesting that the creep of AT42 alloys......
and (5.00±0.02) mm diameter. Tensile creep tests were performed using RD2-3 creep testing machine. Temperature vibration was controlled within ±1 ℃ and the fluctuations along the gauge length were kept... of dislocations in the matrix. When the creep comes to the secondary stage, the lattice misfit can promote the formation of rafted γ'/γ structure and also result in dense γ'/γ interfacial dislocation......