• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2009년도 추계학술대회 논문집
• /
• pp.313-317
• /
• 2009

Electromagnetic forming(EMF) is a high-velocity forming process which uses electromagnetic Lorentz force. Advantages of this forming technique are improved formability, reduction in wrinkling, non-contact forming and applications of various forming process. But the application of electromagnetic forming technique is still limited in industry. Thus for continuous research and development of technique based on experiments, develop the forming equipment and carry out the forming experiments for validation of forming equipment.

• 소성∙가공
• /
• 제19권1호
• /
• pp.38-43
• /
• 2010

Electromagnetic forming (EMF) method is one of high-velocity forming processes, which uses electromagnetic Lorentz force. Advantages of this forming technique are summarized as improvement of formability, reduction in wrinkling, non-contact forming and applications of various forming process. In this study, the EMF apparatus is developed. It is designed to be stored in 10 capacitors connected in parallel, each with a capacitance of $50{\mu}F$ and maximum working voltage of 5kV. The system has capacitance of $500{\mu}F$ and maximum stored energy of 6.25kJ. And EMF experiments are carried out to verify the feasibility of the EMF apparatus, which has enough forming force from the results of EMF experiment. In addition, peak current carrying a forming coil is predicted from theoretical background, and verified the predicted value compared with experimental value using the current measurement equipment. Consequently, EMF apparatus developed in this study can be applied to various EMF researches for commercialization.

• 한국정밀공학회지
• /
• 제30권7호
• /
• pp.733-740
• /
• 2013

The high-velocity electromagnetic forming (EMF) process is based on the Lorentz force and the energy of the magnetic field. The advantages of EMF include improved formability, wrinkle reduction, and non-contact forming. In this study, numerical simulations were conducted to determine the practical parameters for the EMF process. A 2-D axis-symmetric electromagnetic model was used, based on a spiral-type forming coil. In the numerical simulation, an RLC circuit was coupled to the spiral coil to measure various design parameters, such as the system input current and the electromagnetic force. The simulation results show that even though the input peak current levels were at the same level in each case, the forming condition varied due to differences in the frequency of the input current. Thus, the electromagnetic forming force was affected by the input current frequency, which in turn, determined the magnitude of the current density and the magnetic flux density.

• 조명전기설비학회논문지
• /
• 제15권3호
• /
• pp.51-56
• /
• 2001

본 논문에서는 침대평판 전극구조를 구성하여 침전극에 직류 정 ·부 고전압을 인가한 경우 전계와 자계가 직각방향으로 형성되도록 하고 자계가 코로나 방전현상에 미치는 영향을 측정하고 분석하였다. 정의 고전압을 인가한 경우 자계인가에 의해 방전코로나 영역이 확장되고 이때 흐르는 코로나전류가 감소하였고, 절연파괴전압은 증가되었다. 그러나 부의 고전압을 인가한 경우는 방전코로나 영역이 오히려 축소되고 흐르는 전류가 증가되었으며 절연파괴전압은 감소되었다. 이는 전자계가 동시에 존재하는 영역에서 코로나방전에 의해 생성된 전하들의 로렌쯔력에 의한 싸이크로트론 운동 때문인 것으로 생각된다.