In this study, the deformation of friction stir welding on the aluminum battery housing material(AL6063-T5) applied to the electric vehicle was effectively predicted through experiments and numerical simulations. The temperature data were measured during the friction stir welding experiment, and the numerical simulation was carried out using the experimental temperature data. In the heat transfer analysis, the temperature distribution of the structure over time was calculated using the Reynolds equation. The final friction stir welding deformation was calculated by performing the structural analysis using the calculated temperature distribution data over time. The thermal elasto-plastic analysis was performed according to the friction stir welding process conditions and the welding sequences. Finally, the optimum welding condition was derived that the welding speed is 1000 mm/min and the rotation speed of the tool is 2000 RPM.

In this study, the effect of pre-aging treatment for inhibition of natural aging of Al-4.8Zn-1.3Mg alloy by extrusion process was investigated. Firstly, the as-cast microstructure of Al-4.8Zn-1.3Mg alloy billet and its evolution during homogenization(460℃, 4h + 510℃, 5h) were investigated by means of optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), hardness analysis. The as-cast microstructures of Al-4.8Zn-1.3Mg alloy reveal Mg2Zn, Al5Cu, Al3Cu formed between dendrities. After homogenization, MgZn, Al4Cu, Al13Cu phases precipitated into the matrix. In addition, standard deviation of homogenized billet was improved than as-cast billet from 2.62 to 0.99. According to pre-aging(100℃, 1h) Al-4.8Zn-1.3Mg alloy by extrusion process, yield strength and tensile strength deviation improved more than condition by natural aging.

본 실험은 140 mM HCl 60% Alcohol로 유도된 SD rat를 이용해 각 천연물질의 위염 예방효과를 보고자 하였다. 실험에 사용한 천연소재는 질려자, 갯기름나물, 삼채 뿌리이며, 분쇄기를 이용해 분말화 한 후 열수추출하여 사용했다. 그룹별 각 3마리씩 1군(정상대조군), 2군(증류수 투여 후 140 mM HCl 60% Alcohol 실험적 위염 유발), 3군(질려자 추출물 투여 후 140 mM HCl 60% Alcohol 실험적 위염 유발), 4군(갯기 름나물 추출물 투여 후 140 mM HCl 60% Alcohol 실험적 위염 유발), 5군(삼채뿌리 추출물 투여 후 140 mM HCl 60% Alcohol 실험적 위염 유발)으로 분류되어 각 군 별로 시험물질을 경구 투여했다. 3군, 4군 및 5군은 일주일 간 해당하는 천연물질은 300 mg/kg/day로 경구투여 하였다. 투여기간 후 마지막으로 시험물질을 투여한 후, 급성 위염 유발하고 1시간 뒤 희생시켜 위를 적출하였다. 급성 위염으로 인해 손상된 위 조직을 통해 손상면적 측정 및 병리학적 검사를 진행한 결과, 해당 실험은 천연소 재를 투여한 실험군에서 위 점막 손상 및 출혈이 감소하였음을 확인할 수 있었다. 따라서 본 연구는 질려자, 갯기름나물, 삼채뿌리 추출물이 급성 위염 예방에 대한 효과를 가지고 있으며, 기능성 보조제 및 건강기능식품의 유용한 소재로 사용될 수 있을 것으로 판단된다.