In this study, the layered structures of immiscible Fe and Cu metals were employed to investigate the interface evolution through solid-state mixing. The pure Fe and Cu powders were cold-consolidated by high-pressure torsion (HPT) to fabricate a layered Cu-Fe-Cu structure. The microstructural evolutions and flow of immiscible Fe and Cu metals were investigated following different iterations of HPT processing. The results indicate that the HPTprocessed sample following four iterations showed a sharp chemical boundary between the Fe and Cu layers. In addition, the Cu powders exhibited perfect consolidation through HPT processing. However, the Fe layer contained many microcracks. After 20 iterations of HPT, the shear strain generated by HPT produced interface instability, which caused the initial layered structure to disappear.

In this research, a new medium-entropy alloy with an equiatomic composition of FeCuNi was designed using a phase diagram (CALPHAD) technique. The FeCuNi MEA was produced from pure iron, copper, and nickel powders through mechanical alloying. The alloy powders were consolidated via a high-pressure torsion process to obtain a rigid bulk specimen. Subsequently, annealing treatment at different conditions was conducted on the four turn HPT-processed specimen. The microstructural analysis indicates that an ultrafine-grained microstructure is achieved after post-HPT annealing, and microstructural evolutions at various stages of processing were consistent with the thermodynamic calculations. The results indicate that the post-HPT-annealed microstructure consists of a dual-phase structure with two FCC phases: one rich in Cu and the other rich in Fe and Ni. The kernel average misorientation value decreases with the increase in the annealing time and temperature, indicating the recovery of HPT-induced dislocations.

Honey production from approximately 1.7 million colonies owned by around 21 thousand beekeepers was almost 36 thousand M/T in Korea. Pollen has used as a food and medicine from before the Joseon Dynasty period in Korea. Pollen grains such as acorn (Quercus acutissima), actinidia (Actinidia arguta) and green tea (Camellia sinensis) are popular in the markets in Korea. But stiff pollen wall hindered dissolution of polysaccharides and lowered extraction efficiency. In the present study, we measured the antioxidant activity and the total polyphenol content from the pulverized and lyophilized green tea pollen grains inoculated with 6 kinds of fungi to confirm the husk removal effect. The total polyphenol content of green tea pollens was highest in lyophilized pollen medium inoculated with Armillaria mellea, and was lowest in pollen inoculated with Lentinula edodes. Total polyphenol content of the lyophilized pollen was higher than that of the refined pollen and the pulverized pollen in green tea pollen germinated with A. mellea. The total polyphenol content of the lyophilized green tea pollens germinated with A. mellea was 1.4-fold higher than that extracted with water. Measurement of antioxidant activity using the DPPH free radical scavenging method showed that the lyophilized green tea pollen grains germinated with A. mellea had the highest and that germinated with L. edodes was lowest in antioxidant activities. The lyophilized green tea pollen grains germinated with A. mellea was 2 to 4 times higher than that extracted with water in the antioxidant activity of DPPH free radical scavenging. Many germinated cells were formed around pore of green tea pollen inoculated with L. edodes, while those were formed at the end of hyphae derived from green tea pollen grains inoculated with A. mellea.