This study aims at investigating the fracture characteristic according to the shape of the double cantilever beam specimen for mode II with ultra-high strength steel and Mg alloy steel. As the analysis, all three models had the left-hand holes that were constrained by the cylindrical support and the right-hand holes were enforced by the constraint condition of 6mm/min. This study result showed that the shorter the load block of the double envelope test specimen, the higher the safety. The results of this study are thought to be useful for examining the fracture characteristics of specimen for mode II with ultra high strength steel and Mg alloy steel.

ABSTRACT
 1. 서 론
 2. 이중외팔보 시험편의 해석 결과
 3. 결 론
 후 기
 References

• 나우석(Undergraduate student, Division of Mechanical & Automotive Engineering, Kongju National University) | Woo-Seok Na
• 조재웅(Division of Mechanical & Automotive Engineering, Kongju National University) | Jae-Ung Cho Corresponding Author