Hot deformation characteristics and dislocation substructure evolution of a nickel-base alloy considering effects of δ phase
| Autor: | Xin-He Li, Dong-Xu Wen, Yong-Cheng Lin, Swadesh Kumar Singh |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
010302 applied physics
Materials science Mechanical Engineering Metals and Alloys Thermodynamics 02 engineering and technology Strain hardening exponent Strain rate 021001 nanoscience & nanotechnology 01 natural sciences Isothermal process Mechanics of Materials Phase (matter) 0103 physical sciences Materials Chemistry Dynamic recrystallization Substructure Deformation (engineering) Dislocation 0210 nano-technology |
| Zdroj: | Journal of Alloys and Compounds. 764:1008-1020 |
| ISSN: | 0925-8388 |
| Popis: | The hot deformation characteristics of a nickel-base alloy with different contents of δ phase (Ni3Nb) were studied by isothermal compressive experiments. The experimental data and microstructural observation reveal that the hot compressive behavior and dislocation substructure evolution not only relate to the thermomechanical parameters (deformation temperature, strain, strain rate), but also are affected by the content of δ phase. In the initial deformation stage, the dislocation movement is significantly impeded, and the strain hardening behavior is aggravated with increasing the content of δ phase. With the further straining, δ phase exerts the ability for promoting dynamic recrystallization (DRX). Additionally, a new phenomenological constitutive model (PCM) and a deep belief network model (DBNM) are developed to reflect the influence of δ phase. The relative coefficients of the developed PCM and DBNM are 0.992 and 0.998, respectively. The error bands of flow stresses predicted by PCM and DBNM are controlled in ±30 MPa and ±20 MPa, respectively. The high predictability indicates that the developed PCM and DBNM can quantitatively reflect the hot deformation behaviors of the studied alloy with different δ phase contents. |
| Databáze: | OpenAIRE |
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