CAJ | 학술논문

通过无裂纹、单边裂纹和双边裂纹灰铸铁试件对铸铁的拉伸破坏行为进行了试验研究。无裂纹铸铁受到拉伸载荷作用时呈现突然断裂，研究表明在铸铁中加入裂纹后总变形量和刚度降低，试件不会发生突然断裂，表现出一定的韧性特征。当灰铸铁试件中裂纹小于5 mm时，单裂纹试件和双裂纹试件的最大拉伸载荷力/位移曲线的割线刚度基本相同。裂纹纵向间距对双裂纹试件的最大载荷和割线刚度影响较小，但试件达到最大载荷后的变形能力随裂纹纵向间距的增大而增大。
통과무렬문、단변렬문화쌍변렬문회주철시건대주철적랍신파배행위진행료시험연구。무렬문주철수도랍신재하작용시정현돌연단렬，연구표명재주철중가입렬문후총변형량화강도강저，시건불회발생돌연단렬，표현출일정적인성특정。당회주철시건중렬문소우5 mm시，단렬문시건화쌍렬문시건적최대랍신재하력/위이곡선적할선강도기본상동。렬문종향간거대쌍렬문시건적최대재하화할선강도영향교소，단시건체도최대재하후적변형능력수렬문종향간거적증대이증대。
A series of plane-shaped grey iron specimens without cracks, with unilateral crack and with bilateral cracks was produced, and the tensile experiments were performed to investigate the crack propagation and fracture behavior. Brittle fracture appears on the grey iron specimens without cracks. Nevertheless, a little ductility appeared during the tensile processes of the specimens with cracks. The total deformation and secant stiffness of the specimens with cracks were decreased. The maximum tensile load and secant stiffness of the specimens with unilateral crack were close to those of the specimens with bilateral cracks when the crack length is shorter than 5mm. The effect of lon-gitudinal distance between the parallel cracks on the maximum tensile load and secant stiffness is small, and after the tensile load reaches the maximum, the subsequent deformation is increased with the increase of longitudinal distance between the parallel cracks.