Slurry erosion resistance of fusion-bonded epoxy powder coating

Erosion resistance of fusion-bonded epoxy powder coating in emery sand slur ry containing 1 wt.% NaCl has been investigated by using modified rotating disk rig. The effects of emery sand content, flow velocity and diameter of emery particle on the erosion resistance of the coating have been studied t hrough mass loss test and SEM observation. The results showed that the mass loss rate of the coating increased according to a power law with the flow velocity (V), emery particle content (C) and diameter of emery particle (D) . The mass loss rate (E) of the coating could be described by an empirical equation, namely E alpha V-n1 C-n2 D-n3. The relative large values of n(1) and n(3) compared with n(2) indicated that the flow velocity and diameter o f emery particle were the dominant factors. The critical flow velocity of t he coating in slurry containing 10, 15, 20 wt.% emery particle (112 mum) wa s about 7, 6, 5.8 m/s, respectively. Under the test conditions, the first c ritical diameter (FCD) and the second critical diameter (SCD) of emery part icle were about 80 and 410 mum, respectively. Within 80-410 mum, the influe nce of mean diameter of emery particle on erosion was significant. Therefor e, the coating is suitable for the relative mild conditions of liquid-parti cle two-phase flow such as low flow velocity and small particles. (C) 2001 Published by Elsevier Science B.V.