THERMOMECHANICAL PROCESSING OF 13/4 MARTENSITIC STAINLESS STEEL AND ITS SLURRY EROSION BEHAVIOUR

Abstract

13/4 martensitic stainless steel is standard material for hydro turbine blade. A lot of effort is being put to improve wear resistance of this steel further. In view of this, in the present work an effect has been made to improve wear resistance of 13/4 martensitic stainless steel by the way of thermomechanical processing in single phase austenitic region at 1100°C by using thermomechanical simulator, Gleeble 3800. 13/4 martensitic stainless steel samples have been given different amount of deformation viz. (s: -0.2, -0.39,-0.58 ,-0.64,-1) at 1100°C followed by fast cooling (300°C/sec). All the samples have been characterized by optical microscopy and hardness measurement. Slurry erosion test has been performed on as received and thermomechanically treated samples. A thirty two hrs slurry erosion test has indicated that thermomechanically worked sample are superior to as received 13/4 martensitic steel sample. Improvement in wear resistance has been explained from decrease in prior austenite grain size and finer martensitic structure.