The Relation between Applied Stress and Rebound Hardness Values

부가응력과 반발경도와의 관계

  • Nahm, S.H. (Korea Research Institute of Standards and Science) ;
  • Kim, S.C. (Korea Research Institute of Standards and Science) ;
  • Jeon, S.B. (Excelab Inc.)
  • 남승훈 (한국표준과학연구원 소재특성평가센터) ;
  • 김시천 (한국표준과학연구원 소재특성평가센터) ;
  • 전승범 (액셀랩)
  • Published : 1995.12.31


Information of change of hardness values during applying load is needed often to control the quality of metal products efficiently, but the relation between applied stress and hardness has not been established. In this paper the theoretical relation between the rebound hardness and stress was examined briefly and the experiment was performed with some materials. Materials used in test were mild steel(SB41), 7-3 brass and copper, which were widely used in the commercial plants. Hardness was measured during stress applied using the Equo-Tip hardness tester as a kind of rebound hardness tester. Hardness values decreased as tensile stress increased, the decreasing rate was effected by the Young's modulus of each material, and the rebound hardness values showed linear relationship with the applied stress in elastic region.