Superplastic deformation behavior of carbon nanotube reinforced 7055 Al alloy composites

Grain refinement and superplastic deformation behavior of Zn-Al alloys were investigated in this study. To obtain fine grain size in Zn-0.3Al alloys, rolling and equal channel angular pressing (ECAP) were conducted at temperatures from 40 to 160°C after casting and homogenization heat treatment. Material processing maps for Zn-0.3Al alloy were constructed from a series of compression tests conducted at temperatures from RT to 200°C and strain rates from 3×10-2 to 101 s-1. Superplasticity of ECAPed specimens were evaluated at the temperature of 100°C under the strain rate of 2×10-4 s-1. After ECAP of the Zn-0.3Al alloy, elongation was dramatically increased up to 500%. The effects of ECAP on the texture and anisotropy in the superplastic deformation bebavior were found to be negligible.

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Experimental Investigation of the Effect of Temperature and Strain Rate on the Superplastic Deformation Behavior of Ti-Based Alloys in the (α+β) Temperature Field

Metals ◽

10.3390/met8100819 ◽

2018 ◽

Vol 8 (10) ◽

pp. 819 ◽

Cited By ~ 10

Author(s):

Ahmed Mosleh ◽

Anastasia Mikhaylovskaya ◽

Anton Kotov ◽

Waheed AbuShanab ◽

Essam Moustafa ◽

...

Keyword(s):

Strain Rate ◽

Strain Hardening ◽

Deformation Behavior ◽

Superplastic Deformation ◽

Al Alloys ◽

Effect Of Temperature ◽

Al Alloy ◽

Softening Effect ◽

Elongation To Failure ◽

Hardening Coefficient

This paper presents the effect of temperature and strain rate on the superplastic deformation behavior of Ti-3%Mo-1%V-4%Al, Ti-4%V-6%Al, and Ti-1.8%Mn-2.5%Al alloys, which have different initial microstructures. The microstructure, before and after superplastic deformation in the deformation regimes that provided the maximum elongation, was analyzed. The deformation regimes, corresponding to the minimum strain hardening/softening effect, provided a higher elongation to failure due to their low tendency toward dynamic grain growth. As the values of stress became steady (σs), the elongation to failure and strain-hardening coefficient were analyzed under various temperature–strain rate deformation regimes. The analysis of variance of these values was performed to determine the most influential control parameter. The results showed that the strain rate was a more significant parameter than the temperature, with respect to the σs, for the investigated alloys. The most influential parameter, with both the elongation to failure and strain-hardening coefficient, was the temperature of the Ti-3%Mo-1%V-4%Al and Ti-1.8%Mn-2.5%Al alloys and the strain rate of the Ti-4%V-6%Al alloy.

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Mechanical Behavior and Cavitation in Commercial and High Purity Zn-22% Al

MRS Proceedings ◽

10.1557/proc-196-45 ◽

1990 ◽

Vol 196 ◽

Author(s):

Kyung-Tae Park ◽

James C. Earthman ◽

Farghalli A. Mohamed

Keyword(s):

Mechanical Behavior ◽

High Purity ◽

Deformation Behavior ◽

Superplastic Deformation ◽

Impurity Content ◽

Impurity Level ◽

Al Alloy ◽

Impurity Segregation ◽

Different Levels

ABSTRACTAn investigation was conducted on the superplastic Zn-22% Al alloy to examine the effect of impurity level on mechanical behavior and cavitation in the alloy. In conducting the investigation, three grades of Zn-22% Al containing different levels of impurities (6 ppm, 100 ppm, and 180 ppm) were used. The results show that the deformation behavior of Zn- 22% Al at low stresses is influenced by the impurity level of the alloy, and that the extent of cavitation increases with increasing impurity content. These two findings lend support to the concept of attributing low-stress superplastic deformation to strong impurity segregation at boundaries.

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