Practice for Compression Tests of Metallic Materials at Elevated Temperatures with Conventional or Rapid Heating Rates and Strain Rates

Abstract Deformation at elevated temperatures in combination with high strain rates leads to recovery and recrystallization in aluminum alloys. Previous work in recrystallization has emphasized the detailing of microstructural trend in progression from the deformed to the annealed state. In the following, we examine the effect of rate dependence on deformation on AA 5182 and AA 6061. It is demonstrated that identification of underlying microstructural mechanisms is critical. An experimental program is then outlined for characterization of recovery and recrystallization of AA 5182. Instantaneous hardening rate and flow stress are developed from interrupted compression tests. These data are used to establish a quantitative measure of recovery through evaluation of a state variable for work hardening, the mechanical threshold. It is intended that the results serve as a foundation for development of relations for evolution of a mechanical state variable in the presence of recrystallization. Such a framework is necessary for the practical prediction of interstand recrystallization in hot rolling operations.

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Compressive Flow Behavior of AZ61 Mg Alloy at Elevated Temperatures

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.311-313.587 ◽

2011 ◽

Vol 311-313 ◽

pp. 587-590

Author(s):

Horng Yu Wu ◽

Pin Hou Sun ◽

Jie Chen Yan ◽

Jing Hao Liao ◽

Feng Jun Zhu ◽

...

Keyword(s):

Structural Changes ◽

Elevated Temperatures ◽

Flow Behavior ◽

Mg Alloy ◽

Strain Rates ◽

Compression Tests ◽

Flow Curves ◽

Hollomon Parameter ◽

Compressive Flow ◽

Az61 Mg Alloy

The flow behavior and associated structural changes of an AZ61 Mg alloy were analyzed by using hot compression tests in the temperature and strain rate ranges of 250–400 °C and 0.001 to 1 s–1, respectively. The stress–strain curves exhibited the trend typical of materials in which deformation is recovery-controlled in the high Z regime (Z is the Zener–Hollomon parameter), while at low strain rates and high T, the flow curves exhibited a softening typical of recrystallization phenomena. Microstructure analysis has been performed to correlate the microstructure changes to the flow behaviors.

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Workability of ZK60A Alloy Depending on Microstructure

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.217-219.373 ◽

2012 ◽

Vol 217-219 ◽

pp. 373-376 ◽

Cited By ~ 1

Author(s):

K.H. Jung ◽

Yong Bae Kim ◽

Byung Min Ahn ◽

Sang Mok Lee ◽

Jong Sup Lee ◽

...

Keyword(s):

Magnesium Alloy ◽

Uniaxial Compression ◽

Microstructural Evolution ◽

Elevated Temperatures ◽

Electron Backscatter Diffraction ◽

Strain Rates ◽

Compression Tests ◽

Electron Backscatter ◽

Before And After ◽

Backscatter Diffraction

In this study, the variation of workability of semi-continuously casted and extruded ZK60A magnesium alloy was investigated. To determine the deformation capability of two different billets, uniaxial compression tests were conducted at elevated temperatures and two different strain rates. In addition, the microstructural evolution was investigated using electron backscatter diffraction (EBSD) to compare the microstructure before and after the extrusion. The formability of ZK60A depending on the microstructure is discussed based on the experimental results obtained in this study, and is compared with earlier research in the literature.

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Mathematical modeling of AZ30 magnesium alloys at high temperature using the ring compression test and genetic algorithm method

Journal of the Mechanical Behavior of Materials ◽

10.1515/jmbm-2021-0011 ◽

2021 ◽

Vol 30 (1) ◽

pp. 103-109

Author(s):

Farzan Barati ◽

Mona Esfandiari ◽

Sajjad Babaei ◽

Zahra Hoseini-Tabar ◽

Aida Atarod

Keyword(s):

Genetic Algorithm ◽

Strain Rate ◽

Flow Curve ◽

Elevated Temperatures ◽

Optical Microscope ◽

Test Method ◽

Ring Test ◽

Strain Rates ◽

Compression Tests ◽

Ring Compression

Abstract In the present investigation, a new method is proposed to study the AZ30 flow curve at elevated temperatures and various strain rate. Experiments were carried out with the goal of obtaining flow curve of AZ30 at three different temperature and strain rates by using the ring test method. The presented work aims to develop a model using genetic algorithm for AZ30 flow stress prediction during different test conditions. The Santam machine was implicated that was able to perform experiments by controlling both the position and load modes. At each temperature and strain rate the isothermal test was performed respectively. In the present investigation for three varios temperatures and strain rates, 54 ring compression tests were carried out with different levels of reduction in height. Then each specimen was water cooled quickly to investigate the microstructure of AZ30 magnesium alloy by using optical microscope. The model used in the present study was able to predict the flow curve with an 2.3% accuracy. This model has excellent potential to be employed in various industry applications.

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