FRACTURE BEHAVIOR OF HIGH-STRENGTH-STEEL SINTERED STEELS FE-MO-C

This paper presents attempts to tear and tear fracture of steels sintered iron powder with added molybdenum and carbon. Toughness values in the range 27,8-reach 38 MPa. There is a discontinuous crack propagation, fracture is ductile matrix base is easily observed pores transcrystalline and free. Hardness and toughness tests are performed on specimens pre - cracate, they give more information than specimens with notch. Units provide more targets for crack resistance of the material analyzed in comparison with notched specimens. Two grupe of test sample have been obtained from elemental and prealloyed powders. High temperatures sintering lead to increased resistance to mechanical testing of materials and crack propagation will be due to several microvolume between pores. Initial pore morphology changed continuously in the process of sintering.