Influence of Grain Coarsening on the Creep Parameters During the Superplastic Deformation of a Severely Friction Stir Processed Al-Zn-Mg-Cu Alloy

Friction stir processing (FSP) was performed on AA 7075-T6, a heat treatable high strength Al-Zn-Mg-Cu alloy. The two main FSP parameters, the tool rotational and travel speed, were varied systematically in order to understand their influence on the microstructure and mechanical properties of the processed zone. At a given rotational speed, increasing the travel speed increased the microhardness of the nugget (stir) zone; for a given travel speed there appeared to be an optimum rotational speed which resulted in the highest microhardness. The range of FSP parameters used did not significantly influence the nugget zone grain size. It is suggested that the observed mechanical properties are a result of the complex interactions between the FSP thermo-mechanical effects and the processes of dissolution, coarsening and re-precipitation of the strengthening precipitates in this alloy.

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Investigation on friction stir welding of hybrid composites fabricated on Al–Zn–Mg–Cu alloy through friction stir processing

Journal of Materials Research and Technology ◽

10.1016/j.jmrt.2019.06.033 ◽

2019 ◽

Vol 8 (5) ◽

pp. 3733-3740 ◽

Cited By ~ 6

Author(s):

Namrata Gangil ◽

Sachin Maheshwari ◽

Arshad Noor Siddiquee ◽

Mustufa Haider Abidi ◽

Mohammed A. El-Meligy ◽

...

Keyword(s):

Friction Stir Welding ◽

Friction Stir Processing ◽

Hybrid Composites ◽

Friction Stir ◽

Cu Alloy

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Tensile Behavior and Superplastic Deformation of Sn–Bi–Cu Alloy

MATERIALS TRANSACTIONS ◽

10.2320/matertrans.mh201811 ◽

2019 ◽

Vol 60 (6) ◽

pp. 882-887

Author(s):

Junpei Umeyama ◽

Akira Yamauchi

Keyword(s):

Superplastic Deformation ◽

Tensile Behavior ◽

Cu Alloy

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Low-temperature superplastic deformation mechanism in Ti–6Al–4V alloy processed by friction stir processing

Materials Science and Engineering A ◽

10.1016/j.msea.2019.138261 ◽

2019 ◽

Vol 764 ◽

pp. 138261 ◽

Cited By ~ 5

Author(s):

Wenjing Zhang ◽

Hua Ding ◽

Minghui Cai ◽

Wenjing Yang ◽

Jizhong Li

Keyword(s):

Low Temperature ◽

Friction Stir Processing ◽

Deformation Mechanism ◽

Superplastic Deformation ◽

Friction Stir

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Effect of Superplastic Deformation on the Properties of Zirconia Dispersed Alumina Nanocomposite

Materials Science Forum ◽

10.4028/www.scientific.net/msf.551-552.527 ◽

2007 ◽

Vol 551-552 ◽

pp. 527-532 ◽

Cited By ~ 2

Author(s):

Guo Qing Chen ◽

Shao Hua Sui ◽

X.D. Wang ◽

Wen Bo Han

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Flexural Strength ◽

Superplastic Deformation ◽

Critical Dimension ◽

Grain Boundary Sliding ◽

Transformation Toughening ◽

Grain Coarsening ◽

Boundary Sliding ◽

Phase Transformation Toughening

In this paper constrained extrusion of the zirconia dispersed alumina nanocomposite under superplastic conditions was conducted. The mechanical properties of deformed material were studied and its results were compared with those of the initial materials. The microstructure evolution during superplastic deformation was also analyzed. The results demonstrated that after superplastic extrusion the flexural strength, relative density, Vickers hardness as well as fracture toughness of the material increased noticeably. The flexural strength of the deformed composite even retained at a high value of 310MPa at 800°C. The fracture toughness of the material increased from 6.92 MPa·m1/2 to 8.87 MPa·m1/2 after deformation. After superplastic extrusion due to grain boundary sliding and the compressive stress state, the internal porosities in as-sintered materials were eliminated. During extrusion with grain coarsening the effect of t-ZrO2 to m-ZrO2 transformation toughening increased because more zirconia grains reached the critical dimension. Although grain coarsening may cause the decrease of the fracture toughness in some extent, the phase transformation toughening and strengthening dominated. As a result, the mechanical properties of the deformed material were improved.

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