We introduce typical examples of our achievements of industry-academia collaboration such as, SrTiO₃ molecular layer STEP substrate and large sapphire which has good optical properties for KAGRA. Recently, we are developing color sapphire with Shinshu University. And, in this article, growth, coloration, and commercialization of color sapphire is going to be described. There are fruitful advantages for us due to industry-academia collaboration. For example, expertise from an academic point of view was obtained, and characteristic analyses were performed at university. Furthermore, promoting branding in collaboration with universities, we were able to commercialize, improve products and expand sales channels.

  Water is indispensable for our daily life as well as sustainable development of our society. Besides, the Goal 6 of sustainable development goals (SDGs) aims to supply clean and accessible water. We have proposed an innovative crystal growth methodology to elucidate the correlation and regularity between crystal and flux (solvent). The use of flux growth method can lead to control the size (nm to cm), shape (zero dimensional to three dimensional), and/or surface atomic arrangement of the target crystals Herein, we show the flux growth of titanate-based functional crystals with faceted surface features and macrostructures from various flux for water purification applications. There are two topics in this study. The first topic is heavy metal removal from aqueous solution using sodium titanate crystals. The second topic is nuclear waste remediation in the presence of an enormous excess of Na⁺ and Ca²⁺ by layered titanoniobate crystals. We highlight the selective adsorption properties of these functional oxide crystals.

  Al-Si alloy die-casting materials are expected to be used as a heat dissipation product (heat sink) for a head lamp of automobile, because of their superior castability. Their low thermal conductivity, however, hinders their use for a heat dissipation product. Currently, the heat dissipation property could be improved by surface treatments such as painting, however, it is important to improve the thermal conductivity of Al-Si alloy itself. In this research, the crystal growth of intermetallic compounds, which were formed in Al matric was controlled in order to increase the thermal conductivity. The novel Al-Si alloy was successfully developed under the collaboration research between academia and industry. This alloy had a large volume of intermetallic compounds in the microstructure, resulting in the decrease of solute content of solute atoms in Al matrix and then the increase of thermal conductivity.

  Acoustic properties for Ca₃Ta(Ga_1-xAl_-x)₃Si₂O₁₄ [CTGAS(x)], one of the langasite-type piezoelectric single crystals, were investigated by mainly using the ultrasonic microspectroscopy (UMS) technology. Through measurements of bulk wave velocities by the UMS system, dependences of material constants and their temperature coefficients around room temperature on Al substitution content were determine d for 1 inch diameter CTGAS(x) single crystals (x=0 to 0.75) grown by Czochralski (Cz) method It was revealed that all the material constants and the temperature coefficients varied linearly with Al substitution content. A new method for evaluating homoge neity of CTGAS(x) was demonstrated by focusing on difference in contributions of each material constant to acoustic wave velocities depending on the wave modes and propagation directions. Growth of 2 inch CTGAS(0.50) single crystal was tried for the purpose of reducing the cost in the mass production resulting in successful growth of crack free single crystal with higher homogeneity. Finally, based on the numerical calculation using the material constants determined, a prototype resonator using langasite-type single crystal substrate for 8 MHz packaged in 3.2×2.5 mm² was designed and fabricated. It was revealed that the langasite-type resonator had superior properties such as smaller crystal impedance (1/5) and shorter strat-up time (1/10) compared with quartz resonator. These properties will contribute to realization of the low power consumption type IoT device.

  Steel products are used not only for structural materials but also for functional materials, which are mainly ferromagnetic at about room temperature. Since magneto-crystalline anisotropy is important in crystalline ferromagnetic alloys, the crystal orientation and texture of the ferromagnetic alloys are taken into account in application of various devices. Related to the anisotropy, the orientation and texture of the functional ferrous alloys have been extensively investigated. In this paper, recent progresses of investigations on the production and magnetic properties of the functional ferrous materials are reviewed.

  Artificial intelligent including machine learning is promising for a new tool for the novel optimization in various industrial fields. In this article, we introduce our recent results on the optimization of crystal growth of SiC by RF-TSSG by using machine learning and a nonparametric mathematical optimization method. The results show that they must be a powerful tool for the determination of optimum crystal growth condition such as crystal rotation rate, strength of magnetic field and temperature distribution along crucible wall.