Deformation features and tectonic transfer of the Gumubiezi Fault in the northwestern margin of Tarim Basin, NW China

Through field geologic survey,fine interpretation of seismic reflection data and analysis of well drilling data,the differential deformation,tectonic transfer and controlling factors of the differential deformation of the Gumubiezi Fault(GF)from east to west have been studied systematically.The study shows that GF started to move southward as a compressive decollement along the Miocene gypsum-bearing mudstone layer in the Jidike Formation at the Early Quaternary and thrust out of the ground surface at the northern margin of the Wensu Uplift,and the Gumubiezi anticline formed on the hanging wall of the GF.The displacement of the GF decreases gradually from 1.21 km in the east AA′transect to 0.39 km in the west CC′transect,and completely disappears in the west of the Gumubiezi anticline.One part of the displacement of the GF is converted into the forward thrust,and another part is absorbed by Gumubiezi anticline.The formation of the GF is related to the gypsum-bearing mudstone layer in the Jidike Formation and barrier of the Wensu Uplift.The differential deformation of the GF from east to west is controlled by the development difference of gypsum-bearing mudstone layer in the Jidike Formation.In the east part,gypsum-bearing mudstone layer in the Jidike Formation is thicker,the deformation of the duplex structure in the north of the profile transferred to the basin along gypsum-bearing mudstone layer;to the west of the Gumubiezi structural belt(GSB),the gypsum-bearing mudstone layer in Jidike Formation decreases in thickness,and the transfer quantity of deformation of the duplex structure along the gypsum-bearing mudstone layer to the basin gradually reduces.In contrast,on the west DD′profile,the gypsum-bearing mudstone is not developed,the deformation of the deep duplex structure cannot be transferred along the Jidike Formation into the basin,the deep thrust fault broke to the surface and the GF disappeared completely.The displacement of the GF to the west eventually disappeared,because the lateral ramp acts as the transitional fault between east and west part of GSB.

About the Features of Transient to Steady State Deformation of Solids

The features of transient to steady state deformation of solids are theoretically investigated.Modeling of various types of loading was carried out by the Movable Cellular Automata method.A stress state of material at the stage of transient to a steady state is shown to be essentially non-uniform, that may in its turn result in stable structures in velocity field of particles of the material. It may also influence development of deformation at the further stages.

Room temperature tensile deformation behavior of a Ni-based superalloy with high W content

K416B Ni-based superalloy with high W content has good high temperature properties and low cost,which has a great development potential.To investigate the room temperature tensile property and the deformation feature of K416B superalloy,tensile testing at room temperature was carried out,and optical microscopy (OM),scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to analyze the deformation and damage mechanisms.Results show that the main room temperature tensile deformation features of the K416B nickel-based superalloy are dislocations slipping in the matrix and shearing into γ’ phase.The <110> super-dislocations shearing into γ’ phase can form the anti-phase boundary two coupled (a/2)<110> partial-dislocations or decompose into the configuration of two (a/3)<112> partial dislocations plus stacking fault.In the later stage of tensile testing,the slip-lines with different orientations are activated in the grain,causing the stress concentration in the regions of block carbide or the porosity,and cracks initiate and propagate along these regions.

Temperature-Dependent Compressive Deformation Behavior of Commercially Pure Iron Processed by ECAP

To explore the temperature dependence of deformation behavior of BCC structural materials and the relevant effect of pre-annealing, commercially pure iron （CP Fe） produced by equal-channel angular pressing （ECAP） is selected as the experimental material. The influences of deformation temperature T and pre-annealing on deformation behavior, surface deformation characteristics and substructures of ECAP Fe were systematically studied. The results show that ECAP Fe undergoes a remarkable strain softening stage after a rapid strain hardening during uniaxial compression, and the softening degree and the yield strength avs first decrease and then increase with raising temperature. Pre-annealing at 400 ℃ effectively weakens the strain softening degree and increases trys. To understand the influence of deformation temperature on deformation behavior, as well as the relevant pre-annealing effect, deformation and damage characteristics and dislocation structures are studied in detail. In a word, the strain softening of ECAP Fe is associated not only with internal structural instability, but also with temperature, and pre-annealing at 400 ℃ improves high-temperature me- chanical properties of ECAP Fe.

Creep Behaviors of FGH95 Powder Ni-Base Superalloy

This article makes an investigation into the creep behavior and deformation features of FGH95 powder Ni-base superalloy by means of creep curves and microstructural observation. Results show that this superalloy exposes obvious sensibility to the applied temperature and stresses in the experimental range. Microstructure of the alloy consists of γ＇ phase of various sizes and dispersed carbide particles precipitated in the wider crystal boundaries between the powder particles. During the creep, the deformation of the alloy occurs in the form of singleor double-oriented slipping inside the grains, and some of the finer carbide particles are precipitated near the slipping traces. The wide grain boundaries might be broken into the finer grains due to severe deformation. The deformation mechanism of the alloy during creep is thought to be the activation of dislocations of double-oriented slipping, including （1/2）〈 110〉 dislocation inside the γ matrix phase and 〈110〉 super-dislocation inside the γ＇phase. The formation of the stacking faults and （1/3）〈112〉 super-Shockleys partial dislocation configuration is attributed to the decomposition of 〈 110〉 super-dislocation in the γ＇ phase.