Enhancing strength-ductility synergy in an ex situ Zr-based metallic glass composite via nanocrystal formation within high-entropy alloy particles

Ding, Hao; Bao, Xiaoqian; Jamili-Shirvan, Zahra; Jin, Junsong; Deng, Lei; Yao, Kefu; Gong, Pan; Wang, Xinyun

doi:10.1016/j.matdes.2021.110108

Cited by 86 publications

(25 citation statements)

References 62 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These large temperature differences between the top and bottom of the dies can be explained by the inhomogeneous distribution of current density for the asymmetric graphite configuration during the SPS sintering process, as illustrated in Figure 1 . Inhomogeneous distribution of the current density can also occur at the contacting points of the particles [ 46 , 47 ], leading to temperature differences inside the particles during sintering, as well.…”

Section: Resultsmentioning

confidence: 99%

Functionally Graded Al2O3–CTZ Ceramics Fabricated by Spark Plasma Sintering

et al. 2022

View full text Add to dashboard Cite

We studied the fabrication of functionally graded Al2O3–CeO2-stabilized-ZrO2 (CTZ) ceramics by spark plasma sintering. The ceramic composite exhibits a gradual change in terms of composition and porosity in the axial direction. The composition gradient was created by layering starting powders with different Al2O3 to CTZ ratios, whereas the porosity gradient was established with a large temperature difference, which was induced by an asymmetric graphite tool configuration during sintering. SEM investigations confirmed the development of a porosity gradient from the top toward the bottom side of the Al2O3–CTZ ceramic and the relative pore volume distributed in a wide range from 0.02 to 100 µm for the samples sintered in asymmetric configuration (ASY), while for the reference samples (STD), the size of pores was limited in the nanometer scale. The microhardness test exhibited a gradual change along the axis of the ASY samples, reaching 10 GPa difference between the two opposite sides of the Al2O3–CTZ ceramics without any sign of delamination or cracks between the layers. The flexural strength of the samples for both series showed an increasing tendency with higher sintering temperatures. However, the ASY samples achieved higher strength due to their lower total porosity and the newly formed elongated CeAl11O18 particles.

show abstract

Section: Resultsmentioning

confidence: 99%

Functionally Graded Al2O3–CTZ Ceramics Fabricated by Spark Plasma Sintering

et al. 2022

View full text Add to dashboard Cite

show abstract

“…This technology provides a high level of control of the sintering process under constant pressure and high heating rates (10–1000 °C/min) [ 18 , 19 ]. Many scholars point out a key advantage of SPS—its ability to produce the dense materials, including alumina, at low sintering temperatures [ 20 , 21 ]. In the process of solid-phase sintering of powder materials, it is customary to distinguish three stages.…”

Section: Introductionmentioning

confidence: 99%

Investigation of the Densification Behavior of Alumina during Spark Plasma Sintering

et al. 2022

View full text Add to dashboard Cite

The article presents the results of the investigation of the mechanism of the densification behavior of alumina-based ceramics during spark plasma sintering. The role of the heating rates and additives were investigated. The first (initial) stage of sintering was investigated by the Young–Cutler model. The second (intermediate) stage of sintering was investigated as a process of plastic deformation of a porous body under external pressure. It was shown that, at the initial stage, the formation of necks between the particles is controlled by grain boundary diffusion (the activation energy is Qb ≈ 20 kTm). At this stage, accommodation of the shape of the alumina particles is also occurring (an increase in the packing density). The accommodation process facilitates the shrinkage of the powder, which is reflected in a decrease in the effective activation energy of shrinkage at low heating rates (10 °C/min) to Qb ≈ 17 kTm. At heating rates exceeding 10 °C/min, the intensity of the processes of accommodation of alumina particles turns out to be much slower than the existing diffusion processes of growth of necks between the alumina particles. It was shown that the grain boundary sliding mechanism that occurs in the second stage of sintering can play a decisive role under conditions of spark plasma sintering with a high heating rate. The found value of the activation energy at the second stage of sintering is also close to the activation energy of grain–boundary diffusion of alumina (Qb ≈ 20 kTm). The influences of the second phase particles of MgO, TiO2, and ZrO2 on densification behavior of alumina-based ceramics were investigated. Since at the first stage of sintering the densification relates with the formation of necks between the particles of alumina, the additives (0.5% vol) have no noticeable effect on this process. It was also shown that the second phase particles which are located at the grain boundaries of alumina are not involved in the slip process during the second sintering stage. Analysis shows that additives act only in the final (third) stage of spark plasma sintering of alumina.

show abstract

“…Therefore, research on the fabrication of composites that include copper as a metallic filler is still ongoing. The published research results showed that adding additional metallic components such as Cr, Mo, W, or Ni prevents leakage of liquid copper during sintering [16][17][18][19][20][21].…”

Section: Introductionmentioning

confidence: 99%

Al2O3-Cu-Ni Composites Manufactured via Uniaxial Pressing: Microstructure, Magnetic, and Mechanical Properties

et al. 2022

View full text Add to dashboard Cite

This study’s main goal was to obtain and characterize Al2O3-Cu-Ni composites with different metallic phase content. The study analyzed the three series of samples differing in the metallic phase 5, 10, 15 vol.% volume contents. An identical volume share of the metallic components in the metallic phase was used. Ceramic–metal composites were formed using uniaxial pressing and sintered at a temperature of 1400 °C. The microstructural investigation of the Al2O3-Cu-Ni composite and its properties involved scanning electron microscopes observations and X-ray diffraction. The size of the metallic phase in the ceramic matrix was performed using a stereological analysis. Microhardness analysis with fracture toughness measures was applied to estimate the mechanical properties of the prepared materials. Additionally, magnetic measurements were carried out, and the saturation magnetization was determined on the obtained magnetic hysteresis loops. The prepared samples, regardless of the content of the metallic phase in each series, were characterized by a density exceeding 95% of the theoretical density. The magnetic measurements exhibited that the fabricated composites had ferromagnetic properties due to nickel and nickel-rich phases. The hardness of the samples containing 5, 10, 15 vol.% metallic phases decreased with an increase in the metallic phase content, equal to 17.60 ± 0.96 GPa, 15.40 ± 0.81 GPa, 12.6 ± 0.36 GPa, respectively.

show abstract

Enhancing strength-ductility synergy in an ex situ Zr-based metallic glass composite via nanocrystal formation within high-entropy alloy particles

Cited by 86 publications

References 62 publications

Functionally Graded Al2O3–CTZ Ceramics Fabricated by Spark Plasma Sintering

Functionally Graded Al2O3–CTZ Ceramics Fabricated by Spark Plasma Sintering

Investigation of the Densification Behavior of Alumina during Spark Plasma Sintering

Al2O3-Cu-Ni Composites Manufactured via Uniaxial Pressing: Microstructure, Magnetic, and Mechanical Properties

Contact Info

Product

Resources

About