Practice for Extrusion Press Solution Heat Treatment for Aluminum Alloys

2006 ◽  
Author(s):  
Author(s):  
Lifeng Zhang ◽  
Jianwei Gao ◽  
Lucas Nana Wiredu Damoah ◽  
David G. Robertson

In this paper, the Fe-rich phases in and their detrimental effect on aluminum alloys are summarized. The existence of brittle platelet β-Fe-rich phases lowers the mechanical properties of aluminum alloys. The methods to neutralize the detrimental effect of iron are discussed. The use of high cooling rate, solution heat treatment, and addition of elements such as Mn, Cr, Be, Co, Mo, Ni, V, W, Cu, Sr, or the rare earth elements Y, Nd, La, and Ce are reported to modify the platelet Fe-rich phases in aluminum alloys. The mechanism of the modification is briefly described. Technologies to remove iron from aluminum are reviewed extensively. The precipitation and removal of Fe-rich phases (sludge) are discussed. The dense phases can be removed by methods such as gravitational separation, electromagnetic (EM) separation, and centrifuge. Other methods include electrolysis, electro-slag refining, fractional solidification, and fluxing refining. The expensive three-layer cell electrolysis process is the most successful technique to remove iron from aluminum so far.


2004 ◽  
pp. 61-68

Abstract The metallurgy of aluminum and its alloys offers a range of opportunities for employing heat treatments to obtain desirable combinations of mechanical and physical properties such that castings meet defined temper requirements. This chapter discusses the processes involved in solution heat treatment, quenching, precipitation hardening, and annealing of aluminum alloys. The effects of these processes on dimensional stability and residual stresses are also discussed. Troubleshooting and diagnosis of heat treating problems are covered in the concluding section of the chapter.


Metals ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1361
Author(s):  
Shreyas Hebbar ◽  
Lukas Kertsch ◽  
Alexander Butz

A major challenge in processing 7xxx series aluminum alloys is their limited formability at room temperature. In this paper, for the alloys EN AW-7020 and EN AW-7075, various variants of the W-temper forming process are investigated. For both alloys, a good cold formability and a high strength after aging can be achieved. The effects of solution heat treatment or retrogression temperature and holding time, as well as the influence of plastic deformation after quenching, were studied. For various combinations of process parameters, the formability of the as-quenched materials and the hardening performance during artificial aging were examined. For this, hardness measurements and differential scanning calorimetry (DSC) experiments were performed along the entire process chain, to reveal the development of the hardening precipitates. After solution heat treatment and quenching, the yield stress and hardness of both investigated alloys were drastically reduced in comparison to their initial T6 states, while the ductility was significantly increased. By a subsequent simple artificial aging treatment, the same hardness as in the T6 state could be restored. It was observed that plastic deformation immediately after quenching significantly decreased the artificial aging time to achieve the peak hardness. Besides the conventional solution heat treatment process, an alternative retrogression and re-aging procedure was identified for the alloy EN AW-7020. While the heat treatment temperature can be reduced as compared to the conventional solution heat treatment, the formability and hardenability are equally good. In contrast, no such alternative process could be identified for the alloy EN AW-7075.


Author(s):  
Liliang Wang ◽  
Jun Liu ◽  
Jianguo Lin

Aluminum alloy components are important contribution to lightweight transportations for improving energy efficiency. However, formability of aluminum alloys at room temperature often hinders their further applications in the automotive, rail, or aerospace industries. The solution heat treatment, forming, and in-die quenching (HFQ®) process is an advanced forming technology that performs both forming and heat treatment simultaneously in a single operation. Since its inception, a significant amount of research has been made on the process to develop it further and to assess the feasibility of using it to form components with increasingly complicated geometries, from a growing variety of alloys. This entry summarizes the HFQ® research work, with the emphasis on the development, modeling, and applications of the technology for stamping complex-shaped high-strength aluminum panel components.


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