In this study, titanium (Ti) alloy with carbon (C) solid solution was fabricated by laser powder bed fusion (LPBF) from Ti-TiC mixture powder to investigate the effect of C solid solution on microstructure and tensile properties of LPBF Ti alloy. XRD and TEM analysis showed that part of TiC particles was decomposed from the surface during melting process of LPBF and C was solid soluted in α-Ti for Ti-(0.09~0.4 wt%) C. The solid solution of carbon changed the microstructure of the LPBF Ti alloy to fine acicular microstructure due to the martensitic phase transformation. This was also observed in Ti-0.4 wt% C, where solid solution of carbon was not confirmed, suggesting that in Ti-0.4 wt% C, C was once solid solution and precipitated as TiC after phase transformation. LPBF Ti-C alloys showed good strength-ductility, UTS and elongation at break for Ti-0.2 wt% C were 746 MPa and 26.3%, respectively.

In shis study, yield stress equation, flow rules and physical properties of barium titanate (BaTiO₃) are experimentally obtained. These basic equations and coefficient of flow stress are introduced to finite element method and sintering behavior of barium titanate bulk is simulated. From the uni-axis compression test, yield stress equation of BaTiO₃ is expressed by Shima’s equation and flow rule is written by plastic equiation. The coefficient of flow stress of BaTiO₃ is significantly smaller than literature Alumina and the value is different when the grain size is different. The experimental sintering deformation is quantitatively reproduced by numerical simulation, where basic equation and physical properties are exprerimentally introduced. In addition, the coefficient of flow stress could be determined by simulation sensitivily analysis. Through this study, experimentally obtained yield stress equation, flow rules and coefficient of flow stress are numerically validated.

In order to investigate the cause of the liquid phase migration (LPM) and the shape distortion when WC-Co cemented carbides (alloys) undergo a temperature gradient during cooling, round bars of WC-10 mass%Co alloys are inserted halfway under the coil of the induction heating furnace and partially heated at 1673 K. The results showed that Co migrated from the higher temperature side to the lower one and increase of Co content and bar diameter occurred in a zone at the outside of the coil. The alloy containing free carbon had a significantly narrow Co-increased zone and the zone located at a lower temperature. The volume transfer (V) of Co during heating changed in proportional to the square root of the heating time (t). It was considered that the phenomenon was the same as the LPM between a couple of alloys having different Co content in our previous report. We have concluded that the Co-increased zone in this study corresponds to the Co solid-liquid coexistence zone during partial heating and the Co increase is caused by the migration pressure occurred in the zone, which we named Π_SL. Π_SL should be generated because F_WC/Co(S) derived from γ_WC/Co(S) and γ_Co(L)/Co(S) is higher than F_WC/Co(L) derived from γ_WC/Co(L).

The characteristics of high-temperature oxide fuel cells and high-temperature steam electrolysis cells under millimeter-wave irradiation were evaluated and compared with those evaluated under conventional electric furnace heating. A reversible high-temperature electrochemical cell was fabricated using alumina-dispersed zirconia as the electrolyte, lanthanum strontium manganate as the air electrode, and nickel-ziconia based cermet as the fuel one. The power generation characteristic of the fuel cell under millimeter wave irradiation was 32% higher than that of a conventional electric furnace temperature heating, and the steam electrolysis efficiency was also 120% higher under millimeter-wave irradiation than that under conventional one. Impedance measurements using an air electrode-electrolyte half-cell showed that the millimeter wave irradiation facilitated the dissociation of oxygen molecule and/or diffusion of oxygen atoms on the surface of the air electrode as well as the oxide ion conduction in the electrolyte.

It is known that the anisotropic magnetic fields are improved by La and Co substitutions for M-type ferrite sintered magnets, and the coercive forces are significantly improved. On the other hand, since W-type ferrites have a crystal structure similar to that of M-type ferrites, it is expected that La-Co substitution would improve magnetic properties in the same way. However, evaluations of the effects of La and Co substitution are difficult because sintered bodies with a single phase of W-type has not been obtained and sintering at high temperatures is required. Recently, a method to determine the anisotropic magnetic fields using the saturation asymptotic law was proposed by T. Kuno et al., J. Jpn. Soc. Powder Powder Metallurgy 63 (2016) 1053, which makes it possible to evaluate the anisotropic magnetic fields. In this study, La-Co substituted W-type ferrite powders in the Ba, Sr and (Ba-Sr) based systems were prepared, and the effects of La-Co substitution and the ratio of Ba and Sr on the anisotropic magnetic fields were investigated.