Theoretical modelling of slurry erosive wear testing of HVOF thermally sprayed Inconel-Titania coatings

Sekhar N

doi:10.17485/ijst/2012/v5i6.17

Abstract

Material loss due to slurry erosion is a serious problem in many industrial applications like hydraulic turbines, slurry pumps, pipe lines, etc. where the ideal choice of engineering materials is a real challenge. Lightweight aluminum alloys are finding wi de applications in the field of aerospace automobile, defence, etc. due to improved physical, mechanical and tribology properties. HVOF (High velocity oxy fuel ) Sprayed coatings provide protection against corrosion, erosion and wear. Inconel-718 is a metallic coating which has good wear and erosion resistance. This was sprayed on to mild steel substrate and then subjected to slurry erosive wear tests. It is observed that the slurry wear rates of mild steel decreased on coating the substrate material with-718. The tests were conducted in a slurry erosive wear tester at varying spindle speeds (500 -1500rpm) at different intervals of time .The wear loss was recorded experimentallycompared with theoretical values and graphs are plotted to check accuracy. For this comparison, various parameters such as impinging particle size, velocity of solid particles, concentration of slurry bath, h ardness of mild steel, time are correlated to o btain a theoretical formulation. A non -dimensional analysis is also done to reduce the number of parameters influencing the wear rate.

Highlights

Slurry erosion can be defined as a type of wear or loss microns of material experienced by a component, when exposed Hardness to high velocity stream of slurry mixture of solid particles
The mild steel must be protected from chemical attacks, as this can result in inclusions between the grains which in turn affect the toughness of the material
For the tests conducted at a rotational speed of 500 rpm and a slurry concentration of (35 grams NaCl + 100grams silica sand +1 litre water), Mild steel coated with 95% Inconel + 5% titania offered greater resistance to slurry erosion

Summary

Introduction

Slurry erosion can be defined as a type of wear or loss microns of material experienced by a component, when exposed Hardness to high velocity stream of slurry mixture of solid particles. Slurry erosive wear results on coated mild steel for 500 rpm Melting point Density For Mild Steel (without any coatings) - (slurry is 35gNacl+100g silica+1litre water) , there was 0.4 % weight loss.

Results

Conclusion