An Experimental Study on the Damage Mechanism of Particle Impact in a Scratched Glass

표면거칠기를 가진 유리의 입자충격 손상기구에 관한 실험적 연구

  • 서창민 (경북대학교 기계공학과) ;
  • 정성묵 (경북대학교 대학원 기계공학과) ;
  • 이문환 (구미전문대학 자동차과)
  • Published : 1996.07.01


The damage mechanism by the impact of steel ball on the soda-lime glass having a different surface roughness was investigated. An initiation and a propagation behavior of cracks formed by each impact velocity were quantitatively studied. A 4-point bending test was carried out to evaluate the remaining bending strength of a scratched soda-lime glass which impacted by the steel ball. As the surface roughness was increased, the shape of cracks became more irregular rather than those of the smooth specimens. The phenomenon of turning up in the wing of cone cracks occurred even at the lower velocity than the critical velocity caused the crushing. The threshold velocity of cracks initiation generally became lower than those of smooth specimen. An initiation and a propagation behavior of radial cracks had no relation with the direction of scratch on the surface. The remaning benidng strength of the scratched specimen according to impact velocity had no big difference compared with those of the smooth specimen.


Ring Crack;Cone Crack;Lateral Crack;Radial Crack;Crushing;Particle Impact