Wei Liu

• PhD
• Shanghai University

Integrated simulation on dissolution of the body-centered-cubic (bcc, α) phase in the face-centered cubic (fcc, γ) matrix in the ternary Fe–Cr–Ni system is a first step toward the study of phase transformations in steels in the framework of integrated computational materials engineering. The accuracy of the simulation highly depends on the qualitie...

Quantifying the local lattice distortion (LLD) and exploring its correlation with material properties are of fundamental importance for the design of high entropy alloys (HEAs). In the present work, we expressed the LLD as the standard deviation of the bond length (SDBL). With which, we calculated the LLDs of the face-centered cubic (fcc) alloys, i...

The volume of solid solutions mostly deviates from Retgers’ law, namely linearity of volume with respect to composition. Fundamental knowledge is demanded to reveal the regularity behind. In this work, we obtained the molar volume of a series of TM-Co and TM-Ni (TM = Transition Metals, including V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Tc, Ru, Rh, Pd, Ag...

Thermodynamic databases are essential prerequisites for developing advanced materials, such as Ni-based superalloys. The present work collects a large amount of experimental and first-principles calculation data concerning the thermodynamics and phase diagrams of the Ni-Mo-Re system, based on which the thermodynamic properties of the ternary and it...

The investigation of site occupancy behavior is of guiding significance helping establish the sublattice model for describing an intermetallic phase within the framework of computational thermodynamics, and thus facilitates material design. In the present work, we clarified the effects of the influencing factors, including the size and electronic f...

In the present work, the liquidus and solidus for a series of NixCo1-2xCrx alloys were measured by means of differential scanning calorimetry, and the first-principles calculations were performed to obtain total energies for all solid solutions and end-members of the intermediate phases in the Ni–Co–Cr ternary system. Various types of data from the...

Assisted by the first-principles calculations, the molar volumes of γ and γ′ phases in the binary Ni–Al system were modeled within the framework of the CALPHAD method. A CALPHAD database integrating thermodynamic and molar volume descriptions was established. The present Ni–Al binary database was validated to make good predictions of molar volumes/...

In the present work, we modeled the molar volumes of the bcc phases in Co-X (X = Fe, Mo and Zr), Ni-X (X = Fe, Mo and V) and Ti-X (X = Fe, Mo, Nb, Ta and V) binary systems, as well as fcc phases in Co-X (X = Au, Fe, Ge, Hf, Ir, Mo, Nb, Ni, Os, Pd, Pt, Re, Rh, Ru, Sc, Sn, V, Zn and Zr), Ni-X (X = Al, Au, Cr, Cu, Fe, Ga, Ir, Mo, Nb, Os, Pd, Pt, Rh, R...

The formation of the sigma phase in technologically important materials influences greatly their mechanical properties. Fundamental knowledge on the sigma phase is demanded to understand the phase stability and reasonably control its precipitation. The present work clarifies the atomic bonding characteristics of the binary sigma phase including A-A...

The volume modeling of the sigma phase is an indispensable complement to the integrated computational material design of technologically important materials, such as high-alloy steels and Ni-based superalloys. The molar volume of the sigma phase is influenced by both the atomic mixing (the volume variation affected by this factor is caused by compo...

[1909Jae] was the first who estimated the phase equilibria in the Co-Cu-Ni system using the information on the phase relations in the binaries. The first experimental investigation of the system was performed by [1914Wae] who constructed several partial vertical sections and liquidus projection. [1938Vol] and [1943Gue] established a vertical sectio...

The present work systematically clarifies the influence of the atomic mixing and the atomic order (i.e. atomic constituent distribution or site occupancy preference on inequivalent sites of a crystal) on the molar volume of the binary sigma phase. We calculated the molar volumes of 21 binary sigma compounds with different atomic order by using EMTO...

We calculated the atomic volume with respect to the atomic charge of the constituent atoms in the complete set of ordered configurations for several binary sigma systems by using first-principles calculations. The calculation results indicate that both the nearest neighbor (NN) atoms and coordination polyhedron (CP) affect the atomic volume of sigm...

The sigma phase can serve as a prototype of intermetallic phases when investigating the atomic order (i.e. atomic constituent distribution or site occupancy preference on inequivalent sites of a crystal structure), as the sigma phase bears a broad homogeneity range and there are numerous experimental site occupancy data available for the sigma phas...

We have calculated the enthalpy of formation and bulk modulus for 19 typical binary sigma compounds with different atomic order (i.e. atomic constituent distribution or site occupancy preference on inequivalent sites of a crystal structure) based on the experimental site occupancy as well as completely ordered and hypothetically disordered states b...

The molar volume of the C14 Laves phase has been evaluated at room temperature and atmospheric pressure for binary systems involving 31 elemental metals (i.e. Al, Ba, Be, Co, Cr, Fe, Hf, Lu, Mg, Mn, Mo, Na, Nb, Nd, Os, Pr, Re, Ru, Sc, Sm, Sr, Ta, Tb, Ti, Tm, V, W, Y, Yb, Zn and Zr) based on experimental data from the literature by means of the CALP...

The precipitates in 850°C aging 2205 Duplex stainless steel were extracted by the method of carbon extraction replicas. The method makes precipitates disperse uniformly and the contrast between precipitates and matrix distinct. TEM(Transmission Electron Microscope), EDS(Energy Dispersive Spectrometer) and SEM (Scanning Electron Microscope) were app...