{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T01:24:02Z","timestamp":1789089842913,"version":"build-2803163510"},"reference-count":23,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2024,4,28]],"date-time":"2024-04-28T00:00:00Z","timestamp":1714262400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>In order to ascertain the mechanical properties and fracture performance of AA6016 aluminum sheets after cold forming and heat treatment processes, uniaxial tensile tests and fracture tests were conducted under various pre-strain conditions and heat treatment parameters. The experimental outcomes demonstrated that pre-strain and heat treatment had significant impacts on both stress\u2013strain curves and fracture properties. Pre-strain plays a predominant role in influencing the mechanical and fracture properties. The behavior of precipitation hardening under different pre-strains was investigated using Differential Scanning Calorimetry (DSC). The results indicated that pre-strain accelerates the precipitation of the \u03b2\u2033 strengthening phase, but excessive pre-strain can inhibit the heat treatment strengthening effect. To consider the influences of pre-strain and heat treatment, a constitutive model, as well as a predictive model for load\u2013displacement curves, was established using a backpropagation (BP) neural network. An analysis of the number of hidden layers and neuron nodes in the network revealed that the accuracy of the model does not necessarily improve with an increase in the number of hidden layers and neuron nodes, and an excessive number might actually decrease the efficiency of the machine learning process.<\/jats:p>","DOI":"10.3390\/ma17092074","type":"journal-article","created":{"date-parts":[[2024,4,29]],"date-time":"2024-04-29T08:49:24Z","timestamp":1714380564000},"page":"2074","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["The Influence of Cold Forming and Heat Treatment Processes on the Mechanical and Fracture Properties of AA6016 Aluminum Sheets"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-1990-7093","authenticated-orcid":false,"given":"Baitong","family":"Liu","sequence":"first","affiliation":[{"name":"College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816, China"},{"name":"Yangtze Delta Advanced Materials Research Institute, Suzhou 215133, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiahong","family":"Lu","sequence":"additional","affiliation":[{"name":"College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816, China"},{"name":"Yangtze Delta Advanced Materials Research Institute, Suzhou 215133, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shiyao","family":"Huang","sequence":"additional","affiliation":[{"name":"College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816, China"},{"name":"Yangtze Delta Advanced Materials Research Institute, Suzhou 215133, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zuguo","family":"Bao","sequence":"additional","affiliation":[{"name":"College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816, China"},{"name":"Yangtze Delta Advanced Materials Research Institute, Suzhou 215133, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xilin","family":"Li","sequence":"additional","affiliation":[{"name":"Yangtze Delta Advanced Materials Research Institute, Suzhou 215133, China"},{"name":"College of Mechanical and Vehicle Engineering, Chongqing Jiaotong University, Chongqing 400074, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhenfei","family":"Zhan","sequence":"additional","affiliation":[{"name":"College of Mechanical and Vehicle Engineering, Chongqing Jiaotong University, Chongqing 400074, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qing","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816, China"},{"name":"Yangtze Delta Advanced Materials Research Institute, Suzhou 215133, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,4,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"307","DOI":"10.1007\/s12289-011-1051-x","article-title":"Influence of pre-strain and heat treatment on mechanical properties of aluminum sheet","volume":"5","author":"Werber","year":"2012","journal-title":"Int. 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