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Recently, topological phonon states in crystalline materials have attracted significant research interests due to their importance for many fundamental physical phenomena. However, their implication on phonon thermal transport remains largely unexplored. Here, we use both rigorous density functional theory calculations and symmetry analyses to find, surprisingly, that the strain-driven topological phonon phase transition in hexagonal TiO can severely diminish its lattice thermal conductivity (\k{appa}L), with a 78% reduction in \k{appa}L at room temperature. This significant suppression of \k{appa}L is found to be a consequence of increased phonon scattering rates, originating largely from the enlarged three-phonon scattering phase space of heat-carrying acoustic phonons. This is enabled by the breaking of symmetry protected degeneracy of phonon branches, which makes phonon-phonon scattering selection rules easier to satisfy. Our work provides direct evidence for the importance of band topology of phonons in tuning thermal conductivity of topological materials, and also offers a promising route towards controlling solid-state heat transport.

The performance of the cathode is always closely related to the electro-deoxidation process and its current efficiency. In this work, the effect of sintering temperature on the electrical resistivity of an ilmenite concentrate cathode was measured. The results show that the sintering temperature has a significant effect on the electrical conductivity of the cathode. The electrical resistivity of the ilmenite concentrate cathode decreases with increasing of the sintering temperature and increasing of the contact area. Besides, the influence of the cathode porosity on electrochemical process during preparation of Ti-Fe alloy in molten salt was studied. The results also reveal that the porosity of ilmenite concentrate cathode directly affects the electro-deoxidation process. The increasing of porosity is beneficial to the formation of intermediate product (CaTiO3) and improvement of the current efficiency.

The surface tension of liquid Ti-Al alloys at 1758 K was determined by an improved sessile drop method. The surface tension of liquid Ti-Al alloys was calculated using the Butler's model and several modified ideal solution models. Results show that the surface tension of liquid Ti-Al alloy decreases with increased Al concentration. Experimental results agree well with both the Butler's model and the modified ideal solution model. The segregation of Al atoms to the surface occurs at all bulk concentrations of Ti-Al alloys. Al with lower surface tension prefers to segregate on the surface of liquid Ti-Al alloy, whereas Ti with higher surface tension prefers to segregate inside the molten alloy. The effect of surface active solute on the surface tension of liquid Ti-Al alloy was also discussed. Sulfur is found to have a larger effect on the surface tension of alloy. The surface tension of liquid Ti-Al alloy decreases with increased sulfur concentration. Sulfur concentration on the surface is higher than that in the bulk. Thus, the adsorption of sulfur for Ti-Al alloys is a positive adsorption.

As a new structural and functional material, metal foam has been proven to obtain excellent properties when compared with dense ones. In the present paper, the powder metallurgy with a space holder technique was used to prepare magnesium foam. The porosity of the foam ranges from 38.90% to 57.50%, when the elastic modulus decreases from 8.50 GPa to 3.30 GPa, and the initial yield stress decreases from 24.90 MPa to 9.40 MPa. The magnesium foam has lower yield stress and longer stress platform, so it can be used as good cushioning energy absorbing materials.

As the main by-product in the iron-making process, blast furnace slag (BF slag) contains a high amount of sensible heat which is a potential heat source with great value if treated properly. Although several technologies have been investigated during recent decades, few of them can be commercialized successfully. In the previous study, we developed a rotating multi-nozzle cup atomizer (RMCA) for granulating the molten slag. The particle size distribution of the produced slag particle is narrow, the shape is spherical, and the degree of non-crystallization is over 95%. In the current study, the models of the disintegration mechanism, the traveling trajectories and the temperature profile of the slag droplet are established. The particle size is analyzed theoretically and then compared with experimental results. It is found that the predicted results agreed with the experimental results very well. The models can provide guidance for designing commercialized atomizer and optimizing the operation parameters.