Chemistry and tensile properties of a recycled AA7050 via spray forming and ECAP/E

Abstract

The aim of this work is to evaluate the conjugation of advanced processing techniques, such as spray forming, extrusion and ECAP as a processing route for reuse of machining chips generated during aircrafts manufacturing parts from AA7050-T7451 raw material plates supplied according to AMS 4050H1 . In this way, the sprayforming process was used for remelting, and billet production, followed by extrusion and ECAP. At the end of the process, an artificial aging according to AMS 2772E 2 was conducted. An assessment of chemical composition, microstructure, and mechanical properties evolution throughout the process were performed. The results have showed that this proposed route may be used as a potential technological route for secondary aluminum source. For extrusion route for overaged condition, 144 MPa yield strength and 14% of elongation was attained. Beside this, at this stage of work, was verified that the hot extrusion process is more effective for reduction of porosity and microstructure development than ECAP, but on the other hand this one has reduced porosity dispersion significantly for the extrusion parameters adopted. The adopted homogenization schedule, followed by artificial aging after has resulted in excessive grain growth.

Effect Of Hot Pressing On The Electrochemical Properties Of Ti-Ni Alloy

“…This kind of morphology was observed also for Ti-Al coatings fabricated by mechanical alloying [11]. Similar dimples are also obtained for samples which were tensile tested [12,13].…”

Solidification Sequence of Spray-Formed Steels

“…Nevertheless, in cases where the solubility of the alloying elements is higher in the primary phase, for example, Cu-, Zn-, and Mg-containing Al-alloys, the effect of high cooling rates promoted during the atomization stage may be more preserved in the final microstructure, and other considerations should be made. [25] Several authors reported spray-forming as a rapid solidification process, in which it is possible to obtain extended solid solubility, metastable phases, and even amorphous phases. [17,[26][27][28][29][30][31] Achieving such rapid solidification characteristics is indeed possible by spray-forming.…”

Recent Advancements in Material Waste Recycling: Conventional, Direct Conversion, and Additive Manufacturing Techniques

“…After conventional mill annealing process, the material's tensile yield strength was reported to be approximately 1150 Mpa. Hyodo et al [256] recycled AA 7050 machine chips using both conventional and direct conversion methods by following the process of spray forming, hot extrusion, and ECAP.…”