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H.C Yang

Bio: H.C Yang is an academic researcher from Northeastern University (China). The author has contributed to research in topics: Deformation (engineering) & Creep. The author has an hindex of 1, co-authored 1 publications receiving 30 citations.

Papers
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Journal ArticleDOI
TL;DR: In this article, the authors analyzed the relationship between the steady-state creep rate and the applied stress of DZ17G, a modern DS cast nickel-base superalloy used for producing turbine blades and vanes for aeroengine applications.

37 citations


Cited by
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Journal ArticleDOI
TL;DR: In this paper, a physically-based formulation for the back stress based on the Eshelby inclusion formalism is introduced that explicitly depends on morphology of mesoscale dislocation structures.

71 citations

Journal ArticleDOI
TL;DR: In this paper, an advanced constitutive model incorporating two specific aspects of Ni-base superalloy deformation behavior is proposed, which can reasonably predict the material tensile response and creep behaviour for a range of temperatures and stress or strain rate levels.
Abstract: An advanced constitutive model incorporating two specific aspects of Ni-base superalloy deformation behaviour is proposed. Several deformation mechanisms are active in these two-phase materials. In the matrix phase, cube slip plays an important role in the orientation dependence of the material. Moreover, inelastic deformation of the precipitate phase leads to non-Schmid effects in the material response. Macroscopic cube slip is modelled here by incorporating a zig-zag cross slip mechanism into the constitutive relations for the matrix phase. A cross slip factor is proposed that quantifies the amount of cross slip and consequently represents the orientation dependence of the cube slip. Further, a detailed precipitate phase constitutive model is proposed, which enables the simulation of non-Schmid effects, like the tension–compression asymmetry. The cross slip mechanism and the associated splitting of partial dislocations in the γ'-phase, which are responsible for the anomalous yield behaviour, are incorporated in the model. The proposed formulations are implemented in a recently developed crystal plasticity framework for single crystal Ni-base superalloys and a consistent set of model parameters for the commercial alloy CMSX-4 is determined. The model is shown to reasonably predict the material tensile response and creep behaviour for a range of temperatures and stress or strain rate levels. The incorporation of the cross slip mechanisms in the matrix and precipitate results in an adequate simulation of the material orientation dependence and the experimentally determined tension–compression asymmetry.

56 citations

Journal ArticleDOI
TL;DR: In this paper, a mean field mechanical model describing the inelastic behavior and strong anisotropy of Directionally Solidified (DS) materials is developed and its material parameters are calibrated by comparison with the Finite Element (FE) computation of a Representative Volume Element (RVE).

53 citations

Journal ArticleDOI
TL;DR: In this article, the influence of applied stress and temperature on the creep deformation mechanisms of the newly developed nickel-base superalloy M951G have been studied and a creep mechanism map at various creep conditions was summarized and the theoretical critical resolved shear stresses of various creep mechanisms under different temperatures were also calculated.
Abstract: The influences of applied stress (120–760 MPa) and temperature (700–1000 °C) on the creep deformation mechanisms of the newly developed nickel-base superalloy M951G have been studied. The dominant deformation mechanisms of M951G alloy after different creep tests were systematically investigated and the reasons for their transition were well discussed. A creep mechanism map at various creep conditions was summarized and the theoretical critical resolved shear stresses (CRSSs) of various creep mechanisms under different temperatures were also calculated. Results show that the CRSSs of different creep mechanisms display different dependencies of temperature and the favorable deformation mechanisms at different creep conditions are different. τ APB , τ OB and τ CL are decreased to varying degrees with the temperature increasing; on the contrary, there is a positive correlation between τ SF and temperature. At low temperature region, the favorable deformation mechanism is shearing of γ′ precipitates by stacking faults. However, it changes to antiphase boundaries (APBs) coupled dislocation pairs shearing in the γ′ precipitates and dislocation climbing in the γ matrix channel at high temperatures. At intermediate temperatures, both stacking faults and APBs are observed owing to the alternate leading of the CRSSs for APBs and stacking faults shearing in γ′ precipitates.

42 citations

Journal ArticleDOI
TL;DR: In this paper, the authors studied the creep behavior of Ni-based single crystal superalloy with a wide stress regime of 120-174 MPa and found that the dislocation climbing mechanism was the dominant creep mechanism.

38 citations