Comparison of the Heat Treatment Response of SSM-HPDC 6082 and 6004 Wrought Alloys with A356 and F357 Casting Alloys

Abstract

Semi-solid metal high pressure die casting was used to produce plates from traditional wrought AlMg-Si alloys 6082 and 6004, as well as from traditional casting Al-Si-Mg alloys A356 and F357. The high Si-content of the casting alloys offer several advantages, including a faster artificial aging response, higher strength for comparable Mg contents and less sensitivity to prior natural aging on peak strength. However, over-aging occurs earlier in the casting alloys than in the wrought alloys. IntroductionThe Al-Si-Mg alloys that constitute the 6000 series wrought alloys and 300 series casting alloys are heat treatable and depend on age-hardening to develop enhanced strength properties [1]. The main difference between the 300 series and 6000 series is the Si content, with the casting alloys containing a significantly higher quantity [1]. Silicon promotes castability mainly because of the high fluidity imparted by the presence of large volumes of the Al-Si eutectic [1]. The lack of research on the precipitation sequence in Al-Si-Mg casting alloys compared with the Al-Mg-Si wrought alloys has recently been highlighted [2]. In Al-Si-Mg alloys in general, the decomposition of the supersaturated solid solution (SSS) is believed to occur as follows [3]: SSS → (Mg + Si) clusters / GP(I) spherical → β″ / GP (II) needles → β rods ′ → β plates , where GP = Guinier-Preston zones, β = equilibrium Mg 2 Si, β′ and β″ = metastable precursors of β. Semi-solid metal (SSM) processing is a unique manufacturing method to produce near-net shape products for various industrial applications. The aim is to obtain a semi-solid structure which is free of dendrites and with the solid constituent present in a near spherical form. Casting alloys A356/7 are probably the most popular alloys used for SSM forming [4], but one of the main advantages of SSM processing is that it is also possible to produce near net-shape components from alloys that are conventionally wrought such as the 6000 series [5]. The purpose of this paper is to compare the aging response of 6000 series wrought alloys with A356/7 casting alloys produced with the same processing technique with the advantage of having comparable globular primary α-Al microstructures.

The Mechanical Properties of Rheo-High Pressure Die Cast Al-Mg-Si-(Cu) 6xxx Series Alloys

“…Semi-solid metal slurries were prepared using the Council for Scientific and Industrial Research (CSIR) rheocasting process [6]. Either plate [6,7] or taper rod [6,8] castings were cast in steel moulds using a 130 ton LK high pressure die casting machine. The optimal solution heat treatment parameters were determined by Differential Scanning Calorimetry (DSC) [9].…”

Microstructure and Mechanical Property Evaluation of Aluminum F357 Powder for Cold Spray Applications

“…While Al F357 is not utilized as often as its counterpart Al A357, its thermal properties and relatively high strength make it a viable candidate for AM applications. Due to the relative size of the AM community, several suppliers have scaled production of Al F357 powder, increasing the availability of the alloy in powder form (Ref [35][36][37][38][39][40]. In this study, an Al F357 powder was evaluated for its usefulness in CS applications by analyzing the properties of both the powder and cold-sprayed deposits under varying thermal treatments.…”

Effect of the processing parameters on the microstructure and properties of the ZL116 aluminium alloy after vacuum suction casting

“…The ZL116 aluminium alloy is popular as one of Al-Si-Mg series of alloys due to its advantages of good casting fluidity, good air tightness, low shrinkage and low hot-cracking tendency. 1,2 It is most often used in casting. 3 In recent years, the pursuit of light weight in the aerospace and automotive industries also gives the ZL116 aluminium alloy a wide range of applications.…”