iMechanica - strain rate sensitivity
https://imechanica.org/taxonomy/term/3521
enEffect of dynamic plastic deformation on the microstructure and mechanical properties of an Al–Zn–Mg alloy
https://imechanica.org/node/24181
<div class="field field-name-taxonomy-vocabulary-8 field-type-taxonomy-term-reference field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/taxonomy/term/608">research</a></div><div class="field-item odd"><a href="/taxonomy/term/12813">Dynamic plastic deformation</a></div><div class="field-item even"><a href="/taxonomy/term/5791">precipitates</a></div><div class="field-item odd"><a href="/taxonomy/term/3521">strain rate sensitivity</a></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><span>I hope this work on dynamic plastic deformation (DPD) of Al-Zn-Mg alloy is of interest of you. here is the link: </span></p>
<p><a href="https://www.sciencedirect.com/science/article/pii/S0921509320303701">https://www.sciencedirect.com/science/article/pii/S0921509320303701</a></p>
<p><span>Understanding the Al-Zn-Mg alloy behaviour during deformation under different strain rates is of major importance for industrial use. However, only limited data is available to date documenting the microstructural response and the mechanical behaviour of the Al alloy at different strain rates after dynamic plastic deformation processing. Therefore, a more complete understanding of a selected Al-Zn-Mg alloy processed by dynamic plastic deformation and tested under compression at different strain rates is crucial. In this work, We examined the microstructural evolution and the mechanical behaviour of an Al-Zn-Mg alloy under quassi-static compression (1.0 × 10-3 s-1) and under high strain rates (2.0 × 103 s-1 and 4.0 × 103 s-1) after processing by dynamic plastic deformation using the Split Hopkinson pressure bar. </span></p>
<p><span>Materials Science and Engineering: A Volume 784, 15 May 2020.</span></p>
</div></div></div>Sun, 10 May 2020 16:46:11 +0000M.Afifi24181 at https://imechanica.orghttps://imechanica.org/node/24181#commentshttps://imechanica.org/crss/node/24181Strain rate dependence of compressive behavior in an Al-Zn-Mg alloy processed by ECAP
https://imechanica.org/node/23225
<div class="field field-name-taxonomy-vocabulary-6 field-type-taxonomy-term-reference field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/taxonomy/term/76">research</a></div></div></div><div class="field field-name-taxonomy-vocabulary-8 field-type-taxonomy-term-reference field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/taxonomy/term/12477">equal-channel angular pressing</a></div><div class="field-item odd"><a href="/taxonomy/term/5791">precipitates</a></div><div class="field-item even"><a href="/taxonomy/term/12478">Al-Zn-Mg alloy</a></div><div class="field-item odd"><a href="/taxonomy/term/3521">strain rate sensitivity</a></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>Abstract: </p>
<p> <span>Experiments w</span><span>ere</span><span> conducted to study the compressive mechanical properties of </span><span>an </span><span>Al-Zn-Mg alloy</span><span> after <span>solid solution</span></span><span>treatment</span><span> and </span><span>equal-channel angular pressing</span><span> (SS-ECAP)</span><span> using </span><span>strain rates ranging from 1.0x10-3</span><span>to </span><span>3.0x103 s-1. </span><span>The results show that </span><span>SS-</span><span>ECAP </span><span>processing</span><span> enhances</span><span> the </span><span>compressive strength</span><span> due to the </span><span>high dislocation density</span><span>, large numbers of fine precipitates</span><span> and grain refinement. </span><span>The alloy in both the peak-aged (as-received) and the </span><span>SS-ECAP</span><span>states shows a strain rate strengthening effect such that t</span><span>he strain rate sensitivity </span><span>increases </span><span>with increasing strain rate. The</span><span>high volume fraction of fine precipitates </span><span>in the</span><span>SS-</span><span>ECAP </span><span>alloy </span><span>decreases the strain rate sensitivity. The coarse precipitates </span><span>in </span><span>the </span><span>peak-aged </span><span>alloy </span><span>are</span><span> fragmented while </span><span>their </span><span>sizes increas</span><span>e</span><span> in the </span><span>SS-</span><span>ECAP alloy due to </span><span>dynamic precipitation a</span><span>ssisted by the </span><span>high density of </span><span>dislocations</span><span> during compressive testing</span><span>. </span><span>With increasing strain rate, the size of the precipitates further increases for the SS-ECAP alloy</span><span> and this is influenced by accelerated dislocation motion. </span><span>D</span><span>uring compression, </span><span>t</span><span>he </span><span>T (Al20Cu2Mn3) and E (Al18Mg3Cr2) phases</span><span> evolve into a new </span><span>tetragonal </span><span>phase containing </span><span>Mg, Mn, Cr and Zn with Al</span><span>.</span></p>
<p> </p>
<p> </p>
<p>In this paper we had many interesting findings like : </p>
<p><strong><span>High fraction of fine precipitates after SS-ECAP decreases strain rate sensitivity.</span></strong></p>
<p><strong><span>A new </span></strong><strong><span>phase forms evolved from T and E phases during compression.</span></strong></p>
<p><strong><span>for more details the shared link:</span></strong></p>
<p><a class="emtidy-6" href="https://authors.elsevier.com/c/1YrM23IWkbySBO" target="_blank">https://authors.elsevier.com/c/1YrM23IWkbySBO</a></p>
</div></div></div>Sat, 06 Apr 2019 10:45:31 +0000M.Afifi23225 at https://imechanica.orghttps://imechanica.org/node/23225#commentshttps://imechanica.org/crss/node/23225Graduate Studies Opportunities in Montreal
https://imechanica.org/node/13841
<div class="field field-name-taxonomy-vocabulary-6 field-type-taxonomy-term-reference field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/taxonomy/term/73">job</a></div></div></div><div class="field field-name-taxonomy-vocabulary-8 field-type-taxonomy-term-reference field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/taxonomy/term/256">Fatigue</a></div><div class="field-item odd"><a href="/taxonomy/term/1037">high strain rate</a></div><div class="field-item even"><a href="/taxonomy/term/1118">graduate students</a></div><div class="field-item odd"><a href="/taxonomy/term/1365">graduate studies</a></div><div class="field-item even"><a href="/taxonomy/term/3521">strain rate sensitivity</a></div><div class="field-item odd"><a href="/taxonomy/term/6729">shot peening</a></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><strong>GRADUATE STUDIES OPPORTUNITIES IN MONTREAL (CANADA)</strong>
</p>
<p><strong><em>Shot peening for fatigue life </em></strong><strong><em>improvement</em></strong>
</p>
<p>Shot peening is a cold working process in which rigid particles are propelled at<br />
high velocities on a ductile metallic surface. The impacts induce surface<br />
tensile plastic strains in the plane of the treated surface. Since the bulk<br />
material remains elastic, compressive residual stresses develop at the surface.<br />
These stresses retard the apparition of cracks and hence increase the fatigue<br />
life of the treated part.
</p>
<p>Shot peening is largely used in the aerospace industry. In fact, most of the<br />
metallic parts used in aircrafts are submitted to shot peening. The use of shot<br />
peening is strictly regulated and manufacturers have to follow guidelines that<br />
were established many years ago. These regulations were devised based on<br />
extensive trial and error. As a result, the industry, although it successfully<br />
uses the process, has a limited fundamental understanding of its effects. In<br />
some circumstances, shot peening process could be optimized and in other cases,<br />
the process does not produce any beneficial effects and could not be used.
</p>
<p>Four major and one small aerospace companies, one National Research Council research<br />
laboratory as well as École Polytechnique de Montréal, École de Technologie<br />
Supérieure and McGill University have pooled their efforts into a collaborative<br />
research project aiming at understanding the effects of shot peening on fatigue<br />
life. The project will span over 3 years and will involve 11 graduate students.<br />
The project will start in May – September 2013.
</p>
<p>The research team is actively looking for graduate students having backgrounds in<br />
Mechanical Engineering or Metallurgical/Materials Engineering. Applicants<br />
interested in joining the project should send:
</p>
<p><span><span>1.<span> </span></span></span>Brief curriculum vita along with their transcripts;
</p>
<p><span><span>2. </span></span><span><span><span> </span></span></span>A list of publications where one section is devoted to articles<br />
accepted/published in international refereed journals and one other section<br />
where all the other communications (conferences, bo<a name="_GoBack" title="_GoBack" id="_GoBack"></a>oks,<br />
papers not written in English, etc.) are listed;
</p>
<p><span><span>3. </span></span>A one-page letter explaining their expertise and their contributions to research.
</p>
<p>Incomplete or applications not respecting the format listed above will not be considered.
</p>
<p>Applications should be sent electronically to Prof. Richard Chromik at</p>
<p>
richard (dot) chromik (at) mcgill (dot) ca
</p>
</div></div></div>Mon, 10 Dec 2012 02:49:33 +0000Richard R. Chromik13841 at https://imechanica.orghttps://imechanica.org/node/13841#commentshttps://imechanica.org/crss/node/13841Error | iMechanica