Yurong Jiang

Bio: Yurong Jiang is an academic researcher from Central South University. The author has contributed to research in topics: Phase diagram & Ternary numeral system. The author has an hindex of 5, co-authored 6 publications receiving 50 citations.

Phase Equilibria of the Ti-Al-Nb System at 1000, 1100 and 1150 °C

Abstract: 1000, 1100 and 1150 °C isothermal sections of the Ti-Al-Nb system were studied using x-ray diffraction, scanning electron microscopy and electron probe microanalysis. A small island-like region of single β0 is present at 1000, but absent at 1100 and 1150 °C. γ1 is not a stable phase at 1000 and 1150 °C. Three three-phase fields (α2 + β0 + σ, β0 + σ + γ and α2 + β0 + γ) are identified in the 1000 °C isothermal section (30-60 at.% Ti content). The 1100 °C isothermal section is firstly studied completely. It includes six three-phase and thirteen two-phase fields. Two three-phase fields β + α2 + γ and β + σ + γ are identified in the isothermal section (30-60 at.% Ti content) at 1150 °C. These data are helpful to the fabrication of the TiAl and Ti2AlNb intermetallics.

Experimental investigation and thermodynamic assessment of Al–Ca–Ni ternary system

Abstract: The Al–Ca–Ni ternary system has been experimentally investigated and thermodynamically assessed to contribute to the development of a novel Al-base amorphous alloy. A new approach in alloy preparation was used due to the special properties of calcium. With selected equilibrated alloys, the isothermal sections of the Al–Ca–Ni system at 873 and 673 K were obtained by means of scanning electron microscopy, electron probe micro-analysis (EPMA) and powder X-ray diffractometry (XRD). Phase transformation temperatures were measured by differential scanning calorimetry (DSC) analysis. The liquidus projection of this ternary system was determined by identification of primary crystallization phases in as-cast samples and from the liquidus temperatures obtained from DSC analysis. A new ternary compound Al78Ca9Ni13 (referred to as τ 3 here after) has been confirmed to exist in both the 873 and 673 K isothermal sections on the basis of EPMA and XRD analysis. All sample compositions are Al-rich: A1–A4 samples > 72.64 at.% Al, B1–B10, C1–C11 > 45 at.% Al, with only C12 at 36.8 at.% Al. Based on the available data of the binary systems Al–Ni, Al–Ca, Ca–Ni and the ternary system Al–Ca–Ni from the literature and present work, thermodynamic modelling of the Al–Ca–Ni ternary system was performed using the calculation of phase diagram method coupled with first-principle calculations. A set of consistent thermodynamic parameters for the Al–Ca–Ni ternary system was obtained with good agreement with the experimental results in the Al-rich region. The calculated data in the Al-poor region are a very plausible prediction, but not validated.

Thermodynamic evaluation of the phase equilibria and glass-forming ability of the Al–Co–Gd system

Abstract: The Al–Co–Gd system was thermodynamically assessed by means of the CALPHAD (CALculation of PHAse Diagrams) method. The substitutional model was adopted to describe the thermodynamic functions of solution phases and sublattice models were used to describe the intermetallic phases in the ternary system. A set of self-consistent thermodynamic parameters was obtained. Furthermore, by using Turnbull Gibbs free energy empirical equations, the driving forces for crystallization of the primary crystalline phases from the undercooled liquid alloys were calculated. Combining thermodynamic data with Davies–Uhlmann kinetic formulas, the time–temperature–transformation (TTT) curves were obtained. By comparing critical cooling rates calculated from the TTT curves, the glass-forming ability of seven Al–Co–Gd alloys was evaluated. The results agree with the experimental data, which suggests that the combined thermodynamic and kinetic approach may be an efficient way for the evaluation of glass-forming ability.

Experimental investigation of phase relations in Al-Co-Y ternary system

Abstract: Phase relations in the Al-Co-Y ternary system at 1173 K have been established by means of scanning electron microscopy (SEM), electron probe microanalysis (EPMA) and X-ray diffraction (XRD) techniques. Isothermal section at 1173 K of this system was constructed, which consists of 27 three-phase regions and 50 two-phase regions (27wider+23line). The ternary compound τ 5 -AlCo 2 Y 2 has been confirmed to exist and the crystal structure has been preliminarily analyzed with pattern indexing method as well. The intermetallic phase Co 2 Y, Co 3 Y, Co 7 Y 2 , Co 5 Y, Co 17 Y 2, Al 2 Y, τ 4 -AlCoY and τ 5 -AlCo 2 Y 2 were expressed as the formula of Al x Co 2−x Y, Al x Co 3−x Y, Al x Co 7−x Y 2 , Al x Co 5−x Y, Al x Co 17−x Y 2 , Al 2−x Co x Y, Al 1+x Co 1−x Y and Al 1−x Co 2+x Y 2 , respectively.

Improved trade-off between strength and plasticity in titanium based metastable beta type Ti-Zr-Fe-Sn alloys

Abstract: An impressive strengthening ability of Laves phases is favorable to develop titanium alloys with an improved trade-off between strength and plasticity. Therefore, the Ti-xZr-7Fe-ySn (x = 25, 30, 35 wt% and y = 1, 2 wt%) alloys were first designed in such a manner that a Laves phase would precipitate in these alloys and then the investigated alloys were produced by cold crucible levitation melting. A hexagonal close-packed C14 type Laves phase along with a dominant fraction of body-centered cubic β phase are formed in all the as-cast Ti-xZr-7Fe-ySn alloys except in Ti-25Zr-7Fe-2Sn. The volume fraction of the Laves-C14 phase is found to be sensitive to the quantities of Zr and Sn. Amongst all the investigated alloys, Ti-35Zr-7Fe-2Sn shows a better dislocation-pinning ability in terms of dislocation density (3.96 × 1015 m−2), yield strength (1359 MPa) and hardness (437 HV), whereas Ti-25Zr-7Fe-1Sn shows a better deformation ability in terms of compressive strain at failure (36.2%) and plastic strain (31.9%). Crack propagation, regions of dimples and deformation bands are examined in the fracture analyses. Moreover, in this work, Ti-25Zr-7Fe-1Sn exhibits the best strength and plasticity trade-off in terms of a product of ultimate strength and compressive strain at failure (77.4 GPa %).

High-throughput experiments facilitate materials innovation: A review

Abstract: Since the Material Genome Initiative (MGI) was proposed, high-throughput based technology has been widely employed in various fields of materials science. As a theoretical guide, material informatics has been introduced based on machine learning and data mining and high-throughput computation has been employed for large scale search, narrowing down the scope of the experiment trials. High-throughput materials experiments including synthesis, processing, and characterization technologies have become valuable research tools to pin down the prediction experimentally, enabling the discovery-to-deployment of advances materials more efficiently at a fraction of cost. This review aims to summarize the recent advances of high-throughput materials experiments and introduce briefly the development of materials design based on material genome concept. By selecting representative and classic works in the past years, various high-throughput preparation methods are introduced for different types of material gradient libraries, including metallic, inorganic materials, and polymers. Furthermore, high-throughput characterization approaches are comprehensively discussed, including both their advantages and limitations. Specifically, we focus on high-throughput mass spectrometry to analyze its current status and challenges in the application of catalysts screening.