Dynamics of micromechanisms controlling the mechanical behaviour of industrial single crystal superalloys |
| |
Authors: | M Benyoucef A Coujou F Pettinari-Sturmel S Raujol B Boubker N Clément |
| |
Affiliation: | (1) Faculté Des Sciences et Techniques Guéliz, Marrakech, Maroc;(2) Cemes-Loe, 29 Rue J Marvig, 31055 Toulouse, France;(3) Faculte Des Sciences Ben M’Sick, Casablanca, Maroc |
| |
Abstract: | When deforming bulk material, micromechanisms involving moving defects result in mechanical characteristics observed at a
macroscopic scale.In situ straining of microsamples in a Transmission Electron Microscope, provides the unique advantage of observing the dislocation
dynamics involved in such micro-deformation processes under the combined effects of stress and temperature. Here the efficiency
of this technique is illustrated by describing the different obstacles controlling the movement of dislocations in a two-phase
industrial single crystal superalloy. At 25‡ and 850‡C, different core structures of the moving dislocations as well as several
ways of crossing obstacles are described, which concern the movement of dislocations inγ channels, at γ/γ′ interfaces and while shearing γ′ precipitates. From these observations, a quantitative analysis is developed
leading to the evaluation of the critical propagation stresses involved in the channels of the matrix and when crossing the
interfaces. This allows to discuss the various sites of resistance opposed to the dislocation movements and controlling the
macroscopic deformation. |
| |
Keywords: | Superalloys plasticity in situ deformation dislocations |
本文献已被 SpringerLink 等数据库收录! |
|