Calorimetric study of non-isothermal crystallization kinetics of Zr60Cu20Al10Ni10 bulk metallic glass

Zhuang, Yanxin; Duan, Tongfei; Shi, Hongyu

doi:10.1016/j.jallcom.2011.06.112

Cited by 50 publications

(22 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This implies that the lower the heating rate, the more information on phase transformation available in the DSC curves. Similar results are also observed by other researchers [7,8] . Also, one trough or peak in a DSC curve with a high rate could encompass several troughs or peaks in other DSC curves with low rates.…”

Section: Analyses Of Dsc Curvessupporting

confidence: 92%

“…Peaks P1, P2 and P3 of the V3 curve take place 7.0 °C, 13.5 °C and 6.4 °C later than those of the V10 cooling curve, respectively. Research & Development CHINA FOUNDRY DSC measurements given by heating curve V1, it is proposed that trough T1 reflects phase equilibrium reaction (12) as considering T2 for reaction (11) and (10), T3 for reaction (9), T4 for reactions (8), (7), (6) and (5), T5 for reactions (4), (3) and (2), T6 for reaction (1). Reactions (5) and (8) presenting the strongest trough (T4) in heating curve V1 give the largest value of reaction heat (ΔH) for their thermal effect.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Characterization and kinetic modeling of secondary phases in squeeze cast Al alloy A380 by DSC thermal analysis

Zhou

et al. 2017

China Foundry

View full text Add to dashboard Cite

A l-Si-Cu alloys are increasingly used in various automotive applications in the consideration of less weight and less energy consumption versus ironbased alloys. Among the Al-Si-Cu casting alloys, A380 with a silicon content of 7.5-10wt.% is the most widely used one due to its excellent castability, moderately high strengths and low cost [1] . To produce A380-based components, high pressure die casting (HPDC) is usually employed as a primary manufacturing process because of its high production rate and dimensional accuracy and stability. Most components produced by HPDC have relatively thin cross sections with a predominant wall thickness of 5 mm. High-pressure die castings have relatively high gas porosity levels, particularly in an area Abstract: Thermal analyses on squeeze cast aluminum alloy A380 (SC A380) solidified under 90 MPa were carried out to study the microstructure development of the alloy, in which a differential scanning calorimeter (DSC) was employed. During the DSC runs, heating and cooling rates of 1, 3, 10, and 20 °C•min -1 were applied to investigate the heating and cooling effects on dissolution of secondary eutectic phases and microstructure evolution. Various reactions corresponding to troughs and peaks of the DSC curves were identified as corresponding to phase transformations taking place during dissolution or precipitation suggested by the principles of thermodynamics and kinetics. The comparison of the identified characteristic temperatures in the measured heating and cooling curves are generally in good agreement with the computed equilibrium temperatures. The microstructure analyses by scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS) indicate that the distribution and morphology of secondary phases present in the microstructure of the annealed sample are similar to the as-cast A380, i.e., strip β(Si), buck bone like or dot distributed θ(Al 2 Cu), β(Al 5 FeSi) and with relatively thick cross sections, owing primarily to the entrapment of air or gas in the melt during the high-speed injection of turbulent molten metal into the cavity. A recent study indicates that squeeze casting (SC), involving slow laminar filling and the solidification of a molten metal in a closed die under an applied pressure, is capable of eliminating gas and shrinkage porosity and consequently enhancing the tensile properties of A380 castings with very thick sections (25 mm) over the HPDC counterpart [2] . The improved soundness of squeeze cast A380 casting enables thermal treatment for further improvement of mechanical properties. Thus, an in-depth understanding of the kinetic features of the dissolution and precipitation of secondary intermetallic phases in squeeze cast A380 alloy is needed to establish correct thermal treatment processes and comprehend their effect on microstructure evolution.It has been demonstrated in previous studies [3] that the mechanical properties of cast A380 are related to the presence of secondary intermetallic phases and their

show abstract

Section: Analyses Of Dsc Curvessupporting

confidence: 92%

Section: Discussionmentioning

confidence: 99%

Characterization and kinetic modeling of secondary phases in squeeze cast Al alloy A380 by DSC thermal analysis

Zhou

et al. 2017

China Foundry

View full text Add to dashboard Cite

show abstract

“…The crystallization process and kinetics of Zr-based BMGs have been extensively investigated by the isochronal and isothermal DSC annealing technique [19][20][21][22]. In an isothermal annealing process amorphous samples are quickly heated up and held at a temperature in the SCLR.…”

Section: Introductionmentioning

confidence: 99%

Isochronal and isothermal crystallization kinetics of Zr–Al–Fe glassy alloys: Effect of high–Zr content

Hua

Chen

Liu

et al. 2014

Journal of Non-Crystalline Solids

View full text Add to dashboard Cite

“…The sigmoidal shape (Fig. 3) of crystallized fraction with temperature represents the bulk crystallization and excludes the chance of surface crystallization [35]. The above sigmoidal curve represents three different stages of crystallization.…”

Section: Resultsmentioning

confidence: 99%

Non-isothermal crystallization kinetics of Zr52Cu18Ni14Al10Ti6 metallic glass

Prajapati

Kasyap

Patel³

et al. 2015

J Therm Anal Calorim

View full text Add to dashboard Cite

In the present work, the thermal analysis of the bulk metallic glass with composition Zr 52 Cu 18 Ni 14 Al 10 Ti 6 has been done by differential scanning calorimetry (DSC) through non-isothermal method. DSC curves indicate a twostep crystallization process at all four heating rates, i.e., 5, 10, 15, and 20°C min -1 . Non-isothermal crystallization studies of the alloy indicate that kinetics conform to Johnson-MehlAvrami (JMA) model. The master plot method and normalized heat flow curve prove the validity of JMA model. Analysis of the second crystallization event has been done by using various isoconversional and isokinetic methods available in the literature. Activation energy of crystallization increases, whereas the value of Avrami exponent decreases, with increase in crystallized fraction. The fitting curve using Lasocka's empirical relation shows that the influence of the heating rate for secondary crystallization event is larger than the primary crystallization event.

show abstract

Calorimetric study of non-isothermal crystallization kinetics of Zr60Cu20Al10Ni10 bulk metallic glass

Cited by 50 publications

References 27 publications

Characterization and kinetic modeling of secondary phases in squeeze cast Al alloy A380 by DSC thermal analysis

Characterization and kinetic modeling of secondary phases in squeeze cast Al alloy A380 by DSC thermal analysis

Isochronal and isothermal crystallization kinetics of Zr–Al–Fe glassy alloys: Effect of high–Zr content

Non-isothermal crystallization kinetics of Zr52Cu18Ni14Al10Ti6 metallic glass

Contact Info

Product

Resources

About