METHOD DETERMINING HARDNESS Russian patent published in 1999 - IPC

FIELD: testing of materials. SUBSTANCE: in correspondence with invention material with known modulus of normal elasticity and Poisson's ratio is loaded with specified rate with the use of spherical indenter. Dependence of dynamic hardness factor of material on its static hardness and rate of loading is found in advance. Diameter and depth of residual indentation on surface of material are measured. Besides this movement of indenter in process of removal of load and elastic restoration of tested material and indenter in center of contact are measured. Maximum load in force contact of tested material with indenter is found by these parameters by proposed mathematical formula. Later static hardness of material is determined by known dependence. EFFECT: timely determination with increased precision of hardness of materials both under static and dynamic loading of indenter. 1 cl, 1 tbl