Papers by Keyword: AISI T15

Abstract: The purpose of this study is to evaluate the effect of the stages and tempering temperatures in the microstructure, tenacity and hardness of the vacuum sintered high speed steel AISI T15. The material was uniaxial pressing at 700 MPa and sintered in a vacuum furnace at 1275°C. After that, different samples of the materials were submitted to the annealing treatment at 870°C, quenching at 1235°C and tempering (single, double and triple) at 540, 550 and 560°C. Concluded the treatments, Rockwell C measurements of hardness were accomplished and, to evaluate the toughness of the material, TRS (Transverse Rupture Strength) tests were done. Later on, the materials were submitted to the metallographic preparation for microstructure analysis in optical microscopy, SEM, EDX and X-ray diffraction. Finally, each property analyzed was evaluated and correlated with the different tempering stages and temperatures accomplished.

Abstract: The effect of quenching heat treatments on the microstructure of cast and worked commercial steel AISI M2 and hot isostatically pressed as well as IPEN vacuum sintered AISI T15 have been studied. The quenching treatments were carried out from 1160, 1185, 1210 and 1235°C. The average grain size, volume fraction and average size of the primary carbides M6C and MC were determined by scanning electron microscopy and by using the digital image analysis method "Quantikov". An increase in average austenite grain size with increase in quenching temperature was observed for the AISI M2 commercial steel and vacuum sintered specimens. In the case of the AISI T15 steel specimens, increase in quenching temperature did not result in an increase in average grain size, both for the commercial and the vacuum sintered steels. The average size and volume fraction of M6C and MC carbides remained unaltered with increase in quenching temperature.