Slurry Erosion Behaviour of Plasma Thermal Sprayed (50%) WC-Co-Cr and Ni-Cr-B-Si Coatings of Different Thickness on CA6NM Turbine Steel Material

Erosive wear behaviour of hydraulic turbine material i.e. CA6NM is investigated. The samples of CA6NM steel were coated by (50%) WC-Co-Cr and (50%) Ni-Cr-B-Si powder with plasma thermal spray technique. Erosion tests have been conducted on self-made erosion test rig which has varying factors. The comparison has been done for mass loss for coated and uncoated materials at different conditions. The study reveals that the impact velocity, slurry concentration and impact angle are most significant among various factors influencing the wear rate of these coatings. After a fix time weight loss on samples are compared. This technique helps in saving time and resources for a large number of experimental trials and successfully predicts the wear rate of the coatings both within and beyond the experimental domain. The coated samples show better results as compared to uncoated. SEM analysis gives the information about the surface topography of samples.

[1]  S. Luyckx,et al.  Characterization of WC–VC–Co thermal spray powders and coatings , 2007 .

[2]  Harmesh Kumar,et al.  Slurry erosion behaviour of HVOF sprayed WC―10Co―4Cr and Al2O3 + 13TiO2 coatings on a turbine steel , 2012 .

[3]  H. Singh,et al.  Slurry Erosion Mechanism of Hydroturbine Steel: Effect of Operating Parameters , 2013, Tribology Letters.

[4]  Maulana Azad,et al.  PREDICTION OF SILT EROSION IN HYDRAULIC TURBINE USING NON LINEAR REGRESSION MODEL , 2013 .

[5]  A. Marder,et al.  Erosion of thermal spray MCr–Cr3C2 cermet coatings , 1999 .

[6]  S. Joshi,et al.  Effect of grinding on plain fatigue and fretting fatigue behaviour of detonation gun sprayed Cu–Ni–In coating on Al–Mg–Si alloy , 2009 .

[7]  F. Otsubo,et al.  Properties of Cr3C2-NiCr cermet coating sprayed by high power plasma and high velocity oxy-fuel processes , 2000 .

[8]  S. Prakash,et al.  Erosion-corrosion of plasma as sprayed and laser remelted stellite-6 coatings in a coal fired boiler , 2006 .

[9]  Pankaj P. Gohil,et al.  Coalesced effect of cavitation and silt erosion in hydro turbines—A review , 2014 .

[10]  J. Humphrey,et al.  Fundamentals of fluid motion in erosion by solid particle impact , 1990 .

[11]  Y. Iwabuchi,et al.  Metallurgical Characteristics of a Large Hydraulic Runner Casting of Type 13Cr-Ni Stainless Steel , 1982 .

[12]  R. Chattopadhyay,et al.  High silt wear of hydroturbine runners , 1993 .

[13]  Harmesh Kumar,et al.  An overview of slurry erosion control by the application of high velocity oxy fuel sprayed coatings , 2011 .