The Effect of Intermediate Storage Temperature and Time on the Age Hardening Response of Al-Mg-Si Alloys

Røyset, Jostein; Stene, Tore; Sæter, Jan Anders; Reiso, Oddvin

doi:10.4028/www.scientific.net/msf.519-521.239

Cited by 57 publications

(19 citation statements)

References 6 publications

(6 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For instance, in alloy 6082 artificially aged immediately after a solution treatment, the number density of β″ precipitates has been reported to be almost five times higher than that of samples naturally aged for a week followed by the same artificial ageing [12]. This has an adverse effect on the tensile properties of the alloy [1,15]. The opposite, however, is believed to occur in the 6000 series alloys with low alloying element addition [1,13,15].…”

Section: Introductionmentioning

confidence: 88%

“…This has an adverse effect on the tensile properties of the alloy [1,15]. The opposite, however, is believed to occur in the 6000 series alloys with low alloying element addition [1,13,15]. Chang and co-workers [13] described a "positive effect" of natural pre-ageing on precipitation hardening in an Al-0.44at%Mg-0.38at%Si alloy, i.e.…”

Section: Introductionmentioning

confidence: 99%

“…The influence of prior natural ageing time on the subsequent artificial ageing response of Al-MgSi wrought alloys has been an interesting topic and has attracted a lot of research interest [3,[12][13][14][15][16]. In the 6000 series alloys with high alloying element concentrations, clusters formed during natural ageing have been considered to be "robust" during subsequent artificial ageing [1,12].…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Solute nanostructures and their strengthening effects in Al–7Si–0.6Mg alloy F357

et al. 2012

View full text Add to dashboard Cite

The solute-nanostructures formed in the primary α-Al grains of a Semi-Solid Metal cast Al-7Si-0.6Mg alloy (F357) during ageing at 180°C, and the age-hardening response of the alloy have been systematically investigated using transmission electron microscopy, atom probe tomography and hardness testing. A 120-h natural pre-ageing led to the formation of solute clusters and GP zones. The natural pre-ageing slowed down the precipitation kinetics six-fold during 1 h ageing at 180°C, but this effect diminished after 4 h when the sample reached the same hardness as that without the pre-ageing treatment. It reduced the number density of β″-needles to approximately half of that formed in samples without the treatment, and postponed the peak hardness occurrence to 4 h, 4 times that of the as-quenched sample. A hardness plateau developed in the as-quenched sample between 1 h and 4 h ageing corresponds to the growth of 2 the β″ precipitates and a significant concurrent decrease of solute clusters and GP zones. The average Mg:Si ratio of early solute clusters is < 0.7 while that of GP zones changes from 0.8 to 0.9 with increasing in their size, and that of β″-needles increases from 0.9 to 1.2. β″-needles, GP zones and solute clusters are important strengthening solute nanostructures of the alloy. The partitioning of solutes and precipitation kinetics of the alloy are discussed in detail.

show abstract

Section: Introductionmentioning

confidence: 88%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Solute nanostructures and their strengthening effects in Al–7Si–0.6Mg alloy F357

et al. 2012

View full text Add to dashboard Cite

show abstract

“…Another report [22] showed that slow cooling leads to less precipitate number densities because of loss of quenchedin vacancies. Although natural aging (room temperature storage before the isothermal heat treatment) time generally influences the type of atomic clusters and consequently mechanical properties after precipitation [23,24], the slow cooling leads to lower influences on the effects of natural aging [22]. Investigations of effects of quench rates are important since a fast quenching is not always possible in industrial processes because of e.g.…”

Section: Introductionmentioning

confidence: 99%

The effects of quench rate and pre-deformation on precipitation hardening in Al–Mg–Si alloys with different Cu amounts

Saito

Marioara

Røyset

et al. 2014

Materials Science and Engineering: A

Self Cite

View full text Add to dashboard Cite

The effects of quench rate after solution heat treatment in combination with 1% pre-deformation on precipitation hardening in three Al-Mg-Si alloys have been investigated by transmission electron microscopy and hardness measurements during an isothermal heat treatment. The alloys contain different Cu amounts (up to 0.1 wt%) and the same amounts of other solute elements. While a Cu amount below 0.01wt% does not affect precipitation hardening, an addition of 0.1wt% Cu increases hardness due to formation of a fine microstructure having a high number density of short precipitates. A double peak hardness evolution was observed during isothermal heat treatment. This effect was most pronounced for alloys with low quench rate, and less pronounced for alloys with 1% pre-deformation and 0.1wt% Cu addition. The low quench rate also led to wider precipitation free zones. This effect was also less pronounced by 1% predeformation and addition of 0.1wt% Cu.

show abstract

“…This effect is well known for wrought 6082 alloys [8]. Alloy 6004 shows the opposite behaviour, with the maximum hardness being higher when natural aging occurs before artificial aging [8]. The clusters that formed during natural aging in alloy 6082 are known to be relatively stable at typical artificial aging temperature [1], as can be seen by the small initial decrease in hardness during artificial aging of the naturally aged 6082 sample compared to the naturally aged A356 sample in Fig.…”

Section: Resultsmentioning

confidence: 84%

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

Möller¹,

Govender²,

Stumpf

2011

MSF

View full text Add to dashboard Cite

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.

show abstract

The Effect of Intermediate Storage Temperature and Time on the Age Hardening Response of Al-Mg-Si Alloys

Cited by 57 publications

References 6 publications

Solute nanostructures and their strengthening effects in Al–7Si–0.6Mg alloy F357

Solute nanostructures and their strengthening effects in Al–7Si–0.6Mg alloy F357

The effects of quench rate and pre-deformation on precipitation hardening in Al–Mg–Si alloys with different Cu amounts

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

Contact Info

Product

Resources

About