Origin of prestrain-induced cyclic-strain hardening: Multi-scale experimental characterizations and simulations of 7075 aluminum alloyShow others and affiliations
2024 (English)In: Materials & design, ISSN 0264-1275, E-ISSN 1873-4197, Vol. 238, article id 112711Article in journal (Refereed) Published
Abstract [en]
The influence of prefabricated dislocation features induced by rate dependent prestrain on the post-cyclic process in 7075 aluminum alloy exhibits significant variations, which are of great importance in terms of concerns, designs, and discoveries. Considering strain rate dependent prestrain provides diversified hardening stimuli for the subsequent cyclic process. The maximum cyclic stress in the post-cyclic stage was maintained at the same level as the prestress with strain rates ranging from 10-4s-1 to 10-1s-1. Subsequently, by adjusting post-cycling stress amplitude, research was conducted on quasi-plastic amplitude cycle (QPC) and low plasticity amplitude cycle (LPC) loading conditions. Through experimental mechanism analysis, as well as verification through molecular dynamics and crystal plasticity simulations, prestrain induced by rapid strain rates enhanced the hardening during QPC, stemming from the effects of matrix reconstruction strengthening and wavy structured grain boundaries. However, prestrain induced by slow strain rates promoted the hardening during LPC, primarily arising from the non-uniform crystal structures within individual grains, which was achieved through the complex sub-crystal clusters at grain boundaries, along with intracrystal orderly slipping lattice. These findings offer new insights for the optimization of microstructural design through dislocation engineering.
Place, publisher, year, edition, pages
ELSEVIER SCI LTD , 2024. Vol. 238, article id 112711
Keywords [en]
7075 aluminum alloy; Cyclic stability; Rate dependent prestrain; Crystal plasticity; Molecular dynamics
National Category
Other Materials Engineering
Identifiers
URN: urn:nbn:se:liu:diva-201850DOI: 10.1016/j.matdes.2024.112711ISI: 001180858900001OAI: oai:DiVA.org:liu-201850DiVA, id: diva2:1846954
Note
Funding Agencies|The 2023 Open Project of Failure Mechanics and Engineering Disaster Prevention, Key Lab of Sichuan Province [FMEDP202303]; Technology Development Project Foundation of Petro-China Southwest Oil and Gas Field CDB Operating Company; National Natural Science Foundation of China [2023NSFSC0916]; Sichuan Science and Technology Program [20220303-16]; [52205182]
2024-03-262024-03-262024-08-01