Abstract
Aluminum alloys are attractive for a number of applications due to their high specific strength, and developing new compositions is a major goal in the structural materials community. Here, we investigate the Al-Zn-Mg-Cu alloy system (7xxx series) by machine learning-based composition and process optimization. The discovered optimized alloy is compositionally lean with a high ultimate tensile strength of 952 MPa and 6.3% elongation following a cost-effective processing route. We find that the Al8Cu4Y phase in wrought 7xxx-T6 alloys exists in the form of a nanoscale network structure along sub-grain boundaries besides the common irregular-shaped particles. Our study demonstrates the feasibility of using machine learning to search for 7xxx alloys with good mechanical performance.
Highlights
An iterative process will be introduced if the machine-learning model is valid. It includes steps as follows: (π) construct the machine-learning model based on the training data set to establish the composition–UTS relationship; (θ) use the “expected improvement” function[34] as a global selector to recommend the experiments; (ρ) decide whether or not to stop iteration according to the maximum value of “expected improvement” function and the current-highest UTS; and (σ) refit the machine-learning model by incorporating newly generated data points if the stopping criterion is not satisfied
Through the development of nearly a century, 7xxx alloys have been demanded higher in mechanical performance. These alloys have traditionally been developed by screening various compositions and heat treatments based on trial-and-error
They are today being designed with higher contents and more species of alloying elements to improve mechanical properties
Summary
The search space of Al–xZn–yMg–zCu–uTi–vY–wCe, corresponds to a huge space and our objective is to uncover alloys with desired strength over this space as rapidly as possible. If we aim to optimize 7xxx alloys that are planned to be fabricated using advanced techniques such as spray forming and electromagnetic casting, the limits of the main alloying elements can be extended significantly
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
