CFRP 샌드위치 복합재와 알루미늄 폼 코어 CFRP 샌드위치 복합재에 대한 충격 파괴 연구

한국기계기술학회 한국기계기술학회 2016 한국기계기술학회지 Vol.18 No.2

In this study, the fracture property of impact absorption is investigated using the carbon fiber composite material. And this property is compared with the carbon fiber composite material with aluminum foam. Carbon fiber composite material has the high specific strength and rigidity and the superior durability and fatigue life and light weight. On the ground of these properties, this material has been used widely at the fields of airplane, national defence industry, vehicle and the various industrial areas. Aluminum foam can also be applied at the various areas as it is the material with the superior properties. And this foam is the material which can solve the problem on the light weight of particular product. At the condition of the impact energy of 20J, the maximum loads of CFRP sandwich composite and CFRP sandwich composite with aluminum foam core are shown to be 5.7 kN and 6.5 kN respectively. In case of maximum energies, these values are shown to be 19 J and 17.5 J respectively. At the impact energy of 50 J, the maximum loads of CFRP sandwich composite and CFRP sandwich composite with aluminum foam core are shown to be 7 kN and 8.8 kN respectively. In case of maximum energies, these values are shown to be 43 J and 48 J respectively. At the impact energy of 80 J, the maximum loads of CFRP sandwich composite and CFRP sandwich composite with aluminum foam core are shown to be 9.2 kN and 11 kN respectively. In case of maximum energies, these values are shown to be 70 J and 63 J respectively. As the result of this study, the mechanical properties are investigated through the impact experiments on the composites composed of the closed aluminum foam and the carbon fiber reinforced plastic used frequently as absorbents.

파워스티어링 오일탱크의 유체-구조 연성해석에 관한 연구

한국기계기술학회 한국기계기술학회 2016 한국기계기술학회지 Vol.18 No.2

Most of the commercial vehicle steering system is hydraulic. In this system, Breakage and leakage of oil tank is the cause of serious problems to inhibiting the vehicle direction control of the driver. In this paper, FSI(Fluid-Structure Interaction) analysis was performed considering the sloshing of oil in the tank for structural safety evaluation of the power steering oil tank. Additionally, vibration analysis of simple and fast evaluation method was performed by assuming the fluid to mass. As a result, sloshing analysis of oil in the tank was confirmed from the FSI vibration analysis, and it could get the distribution of the flow pressure 8.2kPa~-5.5kPa. Second, stress change of the FSI vibration analysis results was greater in the 33.6MPa to 0.25MPa during the transitional period 2cycle, then it showed a stable result. Third, maximum stress of FSI vibration analysis considering sloshing of the oil was 2.22MPa. maximum stress of vibration analysis assuming the fluid to mass was 4.50MPa and 103% higher than the FSI vibration analysis, but the oil tank was safely evaluate structurally safety factor 14.1. Finally, without the FSI vibration analysis by applying a weight of 0.5 to the result of vibration analysis assumes fluid to mass, it could be obtained results similar to FSI vibration analysis.

고하중용 오일 팬의 고장분석을 통한 생산풀질 향상 연구

한국기계기술학회 한국기계기술학회 2015 한국기계기술학회지 Vol.17 No.5

방공호용 방폭 밸브의 유동해석에 관한 연구

한국기계기술학회 한국기계기술학회 2015 한국기계기술학회지 Vol.17 No.5

소음지도를 이용한 금속재료품 제조공정의 소음저감 순위 결정

한국기계기술학회 한국기계기술학회 2016 한국기계기술학회지 Vol.18 No.2

Assessment of noise exposed population is to check the environment noise level and social influence in order to reduce the risks such as annoyance and disturbance that are generated by environmental noise. Also, this method suggests the preferential noise abatement policy and action plan by accurately finding the area that the noise causes harmful effect to human health. Recently, a noise map, which can predict noise in comprehensive area, is used for the assessment of noise exposed population, breaking from the methods using existing measures. In particular, countermeasure for noise can be considered more effectively by using assessment methods of noise exposed population for specific noise level, area, and building types which are the main input factors in noise maps. In this study, we propose noise reduction ranking decision at manufacturing process of metal material products due to noise map.

전술차량 종감속기패드 고정볼트 파손에 관한 연구

한국기계기술학회 한국기계기술학회 2016 한국기계기술학회지 Vol.18 No.2

The mobility of the tactical vehicle is important for a mission completion and survivability. During the field operation of the MLRS(Multiple Launcher Rocket System), broken bolt was found in a final reduction gear with oil leakage. It was confirmed that the final reduction gear pad bolt was broken with ductile fracture after inspecting and scanning electronic microscope of the bolt. Furthermore, a finite element analysis on the bolt was conducted with regards to the operating conditions in the final reduction gear. Conducting the analysis, there was a possibility of the bolt being damaged when we put rusty spline and the adhesion of hub thrust pad as input parameters. Finally, improvements on the spline in the shaft are expected in the future by utilizing the result of this study.

마늘종구 직립파종기 개발을 위한 크랭크-링크기구 개발

한국기계기술학회 한국기계기술학회 2016 한국기계기술학회지 Vol.18 No.5

The quality of garlic productions and reduction of labor cost which are important to overcome price competition against import garlic. Improving to the quality of garlic production and reducing of labor cost, The garlic seed must be planted with the downward positioning of garlic seed root. This research was conducted to develop a crank-link mechanism for planting garlic seed with the downward positioning of garlic seed root. Computer simulation was conducted for developing a crank-link mechanism. A prototype of developing crank-link mechanism was manufactured and laboratory tests was performed. As results, Followings are achievements in range of plant depth = 50~70 (mm) with tolerance depth 3 mm, planting hole size = 45×50 (mm) with tolerance size 5 mm at planting speed 0.3 m/s.

고속전철 내ㆍ외장재용 알루미늄 6xxx 계열 압출재의 특성 평가

한국기계기술학회 한국기계기술학회 2018 한국기계기술학회지 Vol.20 No.5

In this study, the whole process of 6xxx series aluminum extruded alloy for high speed train interior and exterior parts are characterized. The mechanical properties, and chemical composition of the case materials were evaluated for the 6063, 6061 and 6N01 alloy profiles and compared to the commercial materials and the evaluation results satisfied the standard. The cast product was extruded using the air slip(AS) casting method and the direct casting(DC) method and these were again heat-treated conditions with T5 or T6. The remarkable point is that the extrusion temperature and pressure of 6061 alloy were somewhat higher than those of other alloys. The reason is that 6061 alloy exhibited brittle fracture due to grain boundary segregation even at the tensile fracture surface and the fact that the product used a billet by the direct casting method instead of air slip one. The mechanical properties were evaluated for the 6063, 6061, 6N01 extruded alloys and the evaluation results were analyzed and satisfied the standard properties.

대형기계 및 고출력기계의 소음 정보 데이터베이스

김병삼 한국기계기술학회 2018 한국기계기술학회지 Vol.20 No.3

The study on the database for the noise of the large machine and high power machine. The object of this project is to prepare the countermeasure of the health care according to investigate and database the basic information of the large machine and high power machine. To accomplish the object ; The dimension and noise of the large machine, which is mounted in the factory, was investigated. And the prediction and measurement method of the noise for the machine by manufacturers were investigated. The database of the noise by the machine type and power was built. The measurement and management methods for the machine noise were considered. The database of the noise was built from the measurement data. The major sound sources and frequency range for the large machine and the high power machine were investigated. The noise effect by the large machine and the high power machine was investigated. The application fields are; The setting of the management plan of the noise which generates from the large machine and the high power machine. The effective noise reduction for the major sound source with low cost. The application as the frequency transition considering the psycho-acoustics characteristics.

Instructions to Authors 외

한국기계기술학회 한국기계기술학회 2018 한국기계기술학회지 Vol.20 No.5