Grain Size Effect on the Mechanical Behavior of Metastable Fe-23Cr-8.5Ni Alloy

An Fe-23Cr-8.5Ni alloy was used as a model material to study the grain size effect on the mechanical behavior of metastable duplex metal. Alloy samples with different grain sizes ranging from 0.1 to 2 μm were prepared by cold-rolling and annealing. A structural refinement to about 0.1 μm results in a high yield strength but very limited ductility. A significant improvement of ductility occurred at the grain size of about 0.4 μm. A further increase in grain size results in a decreased strength and a slightly improved ductility. The alloy with a grain size of about 0.4 μm exhibits an excellent combination of strength and ductility, where the yield strength and tensile elongation are increased up to 738 MPa and 29% as compared to 320 MPa and 33% of a coarse-grained (about 2 μm) sample, respectively. The origin of the excellent mechanical properties was attributed to the unique deformation characteristics associated with the transformation induced plasticity and the development of back stress.

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Effect of Grain Size on Mechanical Properties of Mg-0.3at.%Y Dilute Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.941.790 ◽

2018 ◽

Vol 941 ◽

pp. 790-795

Author(s):

Rui Xiao Zheng ◽

Ichiro Kawarada ◽

Wu Gong ◽

Akinobu Shibata ◽

Hidetoshi Somekawa ◽

...

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Yield Strength ◽

High Pressure Torsion ◽

Tensile Elongation ◽

Tensile Tests ◽

Subsequent Annealing ◽

High Yield ◽

Grain Sizes ◽

Mean Grain Size

In this study, a Mg-0.3at.%Y alloy was provided for a severe plastic deformation by high pressure torsion (HPT) and subsequent annealing. After the HPT by 5 rotations, nanocrystalline structures with a mean grain size of 0.23 μm having deformed characteristics were obtained. Fully recrystallized microstructures with mean grain sizes ranging from 0.66 μm to 32.7 μm were obtained by subsequent annealing at various temperatures. Room temperature tensile tests revealed that ultrafine grained (UFG; grain sizes smaller than 1 μm) specimen exhibited very high yield strength over 250 MPa but limited ductility. In contrast, good balance of strength and ductility was realized in fine grained specimens with grain sizes around 2~5 μm. Particularly, the yield strength and total tensile elongation of a specimen with a mean grain size of 2.13 μm were 184 MPa and 37.1%, respectively, which were much higher than those of pure Mg having a similar grain size. The significant effects of grain size and Y addition on the mechanical properties were discussed.

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Investigation on Grain Size Effect of Rolling Texture in Copper

Materials Science Forum ◽

10.4028/www.scientific.net/msf.850.857 ◽

2016 ◽

Vol 850 ◽

pp. 857-863 ◽

Cited By ~ 2

Author(s):

Yao Jiang ◽

Jing Tao Wang ◽

Yue Wang ◽

Jian Yin

Keyword(s):

Grain Size ◽

Cold Rolling ◽

Size Effect ◽

Rolling Texture ◽

Coarse Grained ◽

Grain Size Effect ◽

Shear Texture ◽

Ecap Pass ◽

Ultrafine Grained ◽

Pole Figures

Cold rolling (CR) was conducted on coarse grained (CG) and ultrafine-grained (UFG) coppers, obtained by 1 and 8 passes in the equal channel angel pressing (ECAP), to investigate the effect of grain size on rolling texture. The microstructure was refined to UFG (~420 nm) with the ECAP pass increased to 8, while only band-like CG microstructure was observed in the 1 pass processed copper. The influence of the texture before CR could be excluded as the crystallographic texture kept similar for different ECAP pass. Pole figures (PFs) showed that the shear texture introduced by ECAP was replaced by rolling texture after CR. Furthermore, the rolling texture was a kind of classical copper-type for the CG copper, while a brass-type rolling texture was observed in the UFG copper. TEM results confirmed that the deformation nanotwins were only observed in the UFG copper, while the microstructure of CG copper was further compressed and subdivided. It indicated that the observed differences in rolling texture component and density might be contributed to the grain size effect which resulted in different deformation mechanism and grain subdivision behavior.

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The influence of dislocation climb on the mechanical behavior of polycrystals and grain size effect at elevated temperature

International Journal of Plasticity ◽

10.1016/j.ijplas.2014.06.002 ◽

2014 ◽

Vol 61 ◽

pp. 112-127 ◽

Cited By ~ 32

Author(s):

Minsheng Huang ◽

Zhenhuan Li ◽

Jie Tong

Keyword(s):

Grain Size ◽

Elevated Temperature ◽

Size Effect ◽

Mechanical Behavior ◽

Dislocation Climb ◽

Grain Size Effect

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Evaluation of the Effect of Initial Texture on the Development of Deformation Texture

Textures and Microstructures ◽

10.1155/tsm.6.231 ◽

1986 ◽

Vol 6 (4) ◽

pp. 231-263 ◽

Cited By ~ 13

Author(s):

T. Leffers ◽

D. Juul Jensen

Keyword(s):

Grain Size ◽

Size Effect ◽

Deformation Texture ◽

Coarse Grained ◽

Grain Size Effect ◽

Fine Grained ◽

Random Texture ◽

Starting Conditions ◽

Initial Texture ◽

Computer Procedure

We describe a computer procedure which allows us to introduce experimental initial textures as starting conditions for texture simulation (instead of a theoretical random texture). We apply the procedure on two batches of copper with weak initial textures and on fine-grained and coarse-grained aluminium with moderately strong initial textures. In copper the initial texture turns out to be too weak to have any significant effect. In aluminium the initial texture has a very significant effect on the simulated textures—similar to the effect it has on the experimental textures. However, there are differences between the simulated and the experimental aluminium textures that can only be explained as a grain-size effect. Possible future applications of the procedure are discussed.

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