INFLUENCE OF THE MARTENSITE VOLUME FRACTION ON THE RECIPROCATING SLIDING BEHAVIOUR OF Ti-Nb MICROALLOYED STEEL

TUCKART W.; JENKO D.; FOCHESATTO N.; BUEZAS, F; LORUSSO H.; SVOBODA H.

TRIBOLOGY TRANSACTIONS

TAYLOR & FRANCIS INC

Lugar: Londres; Año: 2014 vol. 57 p. 146 - 155

1040-2004

The objetive of this work was to evaluate the influence of martensite fraction on the wear mode and the energy dissipation by friction of Dual Phase (DP) steel tested under reciprocating sliding conditions. For this purpose, a Ti-Nb microalloyed steel was heat treated in a conventional furnace at temperatures between 780 ºC and 880 ºC (intercritical annealing temperature) for 3 min to obtain DP microstructures with volume fractions of martensite between 25% and 90%. Wear tests were carried out in both DP and as received samples, using a reciprocating tribometer with ball on flat geometry, at two constant applied loads, 2.5 N and 4 N. The wear damage of each sample was measured through volume loss and the dissipated energy during the test. The obtained results evidenced a significant influence of the contact load over the wear mode, since at low load the DP wear was reduced with increased hardness, but just up to 75% of martensite. At high load, the sliding process promotes an oxide mixture in the ferritic microstructure that acts as a factor of wear reduction