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This study developed a drying method and a dryer that are optimized for shiitake mushrooms. They are mainly being cultivated and consumed as food and medicine in Korea, Japan, China, and Southeast Asia. They generally contain lots of moisture. For this reason, the use of a dryer causes problems such as decomposition and spoilage, and natural dry processing is preferred. To resolve these problems, various drying methods have been proposed (e.g. hot air drying, heat pump vacuum drying) but there has been a difficulty in maintaining a medium-temperature range of 30 to 40°C, the optimal temperature environments for retaining their main components. The study developed a 2-stage decompresses resistive heat pump dryer that can operate also in medium-temperature environments - existing decompresses heat pump dryers have been able to operate only in high-temperature environments. A dryer optimized for shiitake mushrooms that are being produced and distributed in large quantities was proposed, and the utility of the machine was proved through experiments.

Organization of Advanced Sustainability Initiative for Energy System/Material (OASIS), at Muroran Institute of Technology is now intensively enforcing its efforts for industrialization of advanced SiC/SiC composites and SiC based composites by fabrication system integration of NITE method. This paper provides the brief review of the activities at OASIS, where prototype production line of green sheets and prepreg sheets are under installation. The near-net shaped preforms with the NITE green-sheets and prepreg-sheets are made into near-net shape components for potential applications under consideration by HIP and Pseudo-HIP. Aiming at the near term utilization, SiC/SiC hybrid structures with metallic materials, such as steels and other refractory metals, were fabricated with promising results. Trial to reduce the production cost has been continued.

Large volumetric shrinkage (~50 Vol%) occurs during ceramic matrix composites fabrication by hot-pressing due to infiltration and densification process of powder for matrix formation, resulting in unfortunately significant fiber-architecture and -strength damage. This study tries to explore damage-less near-net shaping technique by preform densification before hot-pressing in Nano-Infiltration and Transient Eutectic-phase (NITE) process. In particular, effects of preform densification for the damage-less near-net shaping, important influencing elements such as fiber-architecture, microstructural integrity and homogeneity, and composite's mechanical properties were evaluated using simple shaped (plate) and complex shaped composites. The preform densification demonstrated protective fiber-architecture in complex shaped composites and enhanced composites' density to 2.77/cm3 and ultimate bending strength to ~200 MPa in simple shaped composites, owing to significantly reduced volumetric shrinkage.

NITE-SiC, SiC/SiC qualification of environmental resistance in various conditions is on-going toward early utilization in advanced energy and aero-space systems. Multi-layered SiC/SiC composites for preventing environmental attacks to pyrocarbon interphase was provided. Thermal exposure test in air and liquid metal(Pb and Li-Pb) compatibility test were carried out. It was confirmed the significant loss of PyC interphase in SiC/SiC composites. In case of Li-Pb-layered SiC/SiC composites, an attack of air and liquid metal has been sucessfuly supressed by surface SiC layer

For nuclear and fusion materials R&D, high dose neutron irradiation at very high temperature is one of the most important and challenging techniques. As the part of Japan/EU Broader Approach (BA) program for fusion, International Fusion Materials Irradiation Facility/Engineering Validation and Engineering Design Activities (IFMIF/EVEDA) project is on-going. Where, High Flux Test Module (HFTM) design aiming up to 1000°C has been intensively investigated. Innovative SiC/SiC and tungsten embedded SiC/SiC (W/SiC/SiC) heaters have been recognized potential and promising candidates. These heaters were fabricated successfully by NITE method and were evaluated. The SiC/SiC heater showed weak temperature dependence up to 1000°C on in-plane electrical conductivity. Irradiation capsule for heater performance evaluation under neutron irradiation in Belgian Reactor 2 (BR2) is also under preparation. The results of heater performance and basic properties evaluation and of underlying microstructure behavior analysis are provided.

Although, SiC/SiC composites are very attractive for applications at high-temperature including advanced nuclear fusion/fission plants, their high material cost has been one of biggest issues to be utilized. In the neutron irradiation environments, high crystallinity of SiC fibers and matrix is essential to stabilize the mechanical properties, but the expensive crystallized SiC fibers may enhance the cost of material. As a potential option from the cost down aspect, utilization of amorphous SiC fibers was planned. This paper concerns about the radiation damage tolerance of SiC/SiC with amorphous SiC fibers as starting reinforcing fibers. The crystallization procedure of amorphous SiC fibers was investigated during thermal treatments, and a new NITE-SiC/SiC, called as IC-NITE (IC stands for in-situ crystallized), composite was produced. Its radiation damage behaviour and microstructural stability were examined by a heavy ion irradiation experiment and TEM.

For fusion energy realization, attractive energy conversion system and fuel supply system are essentially required. The current ITER test blanket module study has dual coolant lithium lead (DCLL) system as the attractive blanket option. The concept of making ceramic thermal insulation panels for DCLL blanket has been presented, however, realistic material systems have not been proven so far. This work is trying to present the porous SiC/SiC thermal insulation panel based on the current NITE-method technology. Typical panels with through thickness and in-plane channels and porosities tailored were designed, fabricated and evaluated, successfully. Thermal conductivity of those panels were controlled, as designed, and the tailoring capability of thermal conductivity by NITE-method was presented. This concept and technology can satisfy the basic material requirements as well as economical requirements and large scale production requirements.

ITER project is progressing and the structural material of the blanket will be conventional stainless steels. In the future, the SiC/SiC composites will be employed as the important part of the reactor. Main construction of the reactor will be keep stainless steels such as SUS316L and RAFM steels, the interface technology of SiC and steels will be essential. There are many situation of to connect the SiC component and steel structures, the development of technology for the connecting is not enough. Mismatch of coefficients of thermal expansion (CTE) prevent the simple diffusion bonding of plates, normally insert materials are used to absorb the mismatch of the CTE. There is a possibility to use the CTE mismatch for the connecting, and in present research, some fundamental researches of potential techniques to connect SiC/SiC composites and steels using the metallurgical method have been developed and investigated.