Structure and strain hardening of low stacking fault energy FCC alloys at large strains

2021 ◽  
Author(s):  
Sirous Asgari
Keyword(s):  
Strain Hardening ◽  
Stacking Fault ◽  
Stacking Fault Energy ◽  
Large Strains ◽  
Fcc Alloys

scholarly journals Correlation of Grain Size, Stacking Fault Energy, and Texture in Cu-Al Alloys Deformed under Simulated Rolling Conditions

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Ehab A. El-Danaf ◽  
Mahmoud S. Soliman ◽  
Ayman A. Al-Mutlaq
Keyword(s):  
Grain Size ◽  
Strain Hardening ◽  
Mechanical Twinning ◽  
Al Alloys ◽  
Stacking Fault ◽  
Stacking Fault Energy ◽  
Wide Range ◽  
Orientation Density ◽  
Pure Cu ◽  
Strain Hardening Rate

The effect of grain size and stacking fault energy (SFE) on the strain hardening rate behavior under plane strain compression (PSC) is investigated for pure Cu and binary Cu-Al alloys containing 1, 2, 4.7, and 7 wt. % Al. The alloys studied have a wide range of SFE from a low SFE of 4.5 mJm−2for Cu-7Al to a medium SFE of 78 mJm−2for pure Cu. A series of PSC tests have been conducted on these alloys for three average grain sizes of ~15, 70, and 250 μm. Strain hardening rate curves were obtained and a criterion relating twinning stress to grain size is established. It is concluded that the stress required for twinning initiation decreases with increasing grain size. Low values of SFE have an indirect influence on twinning stress by increasing the strain hardening rate which is reflected in building up the critical dislocation density needed to initiate mechanical twinning. A study on the effect of grain size on the intensity of the brass texture component for the low SFE alloys has revealed the reduction of the orientation density of that component with increasing grain size.

Plastic deformation of FCC alloys at cryogenic temperature: the effect of stacking-fault energy on microstructure and tensile behaviour

2017 ◽  
Vol 52 (12) ◽  
pp. 7466-7478 ◽  
Author(s):  
Danielle Cristina Camilo Magalhães ◽  
Andrea Madeira Kliauga ◽  
Maurizio Ferrante ◽  
Vitor Luiz Sordi
Keyword(s):  
Plastic Deformation ◽  
Cryogenic Temperature ◽  
Stacking Fault ◽  
Stacking Fault Energy ◽  
Tensile Behaviour ◽  
Fcc Alloys

scholarly journals Recent Developments on the Microstructural Effects Caused by Small-Charge Explosions in FCC Alloys

2010 ◽  
Vol 638-642 ◽  
pp. 1029-1034
Author(s):  
Donato Firrao ◽  
Paolo Matteis ◽  
Chiara Pozzi
Keyword(s):  
Blast Wave ◽  
Stacking Fault ◽  
Stacking Fault Energy ◽  
Target Distance ◽  
Deformation Mechanisms ◽  
Charge Mass ◽  
Fcc Alloys ◽  
Fcc Metal ◽  
Wave Properties ◽  
Small Charge

Metals exposed to small charge explosions, even in absence of overall deformation, show characteristic and permanent microstructural features, that can be related to blast wave properties, e.g. to the charge mass and the charge-to-target distance. In particular, Face Centered Cubic (FCC) alloys with low stacking fault energy may exhibit mechanical twinning due to the high strain rate caused by an explosion, even if in slower processes they mainly deform by slip. In some forensic science investigations, these crystallographic modifications, and particularly the occurrence of twinning, may be among the few remaining clues of a small charge explosion, and may be useful to hypothesize the nature and location of the charge. A wide experimental campaign was performed to correlate the blast wave properties with the ensuing modifications of FCC metal targets, and to investigate the microscopic deformation mechanisms leading to these modifications. In particular, it was attempted to identify the threshold conditions (charge-to-target distance, charge mass, and hence applied stress) that yield barely detectable microstructural modifications, and to study the transition from slip to twinning. FCC metal alloys, with low (α-brass, stainless steel), intermediate (copper, gold alloy), or high (aluminum alloy) stacking fault energy, were exposed to blast waves (caused by 50 or 100 g plastic explosive charges located at increasing charge-to-target distances) and then analyzed by X-ray diffraction, optical microscopy, scanning electron microscopy, and electron backscattered diffraction imaging. A comprehensive review of the most significant findings of the whole research, together with theoretical considerations on the slip and twinning deformation mechanisms, is here presented.

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