1·By comparing fatigue crack with electrosparking crack, the effects of crack tip on fracture toughness of ductile iron have been studied.
通过开疲劳裂纹和线切割裂纹的对比试验，研究裂纹尖端的尖锐程度对球墨铸铁断裂韧性的影响；
2·Therein, a certain view point is proposed in the paper, about the spark discharging principle on electrosparking surface to be strengthened.
对电火花表面强化的火花放电原理提出了一定的看法。