Hard arc-sprayed coating with enhanced erosion and abrasion wear resistance

A cored wire formulation, referred to as Alpha 1800, has been developed to produce tailored are-sprayed coatings that are tough enough to resist parti cle impacts at 90 degrees and sufficiently hard to deflect eroding particle s at low impact angles. One millimeter thick coatings composed of ductile a nd hard phases with a Knoop hardness reaching 1800 kg/mm(2) were easily pro duced by arc spraying the cored wire with air. Coatings were (1) erosion te sted at 25 degreesC and higher temperatures at impact angles of 25 and 90 d egrees in a gas-blast erosion rig, (2) slurry erosion tested at impact angl es of 25 and 90 degrees, and (3) abrasion wear tested using the ASTM G-65 t est procedure. Results show that coatings produced with the new cored wire are at least 5 times more erosion resistant and 10 times more abrasion resistant than coat ings produced by arc spraying commercial cored wires. The performance of th e new are-sprayed coating can be compared with that of high-energy WC-based coatings. Maintaining their erosion resistance after being exposed to temp eratures up to 850 degreesC and possessing good oxidation resistance, are-s prayed coatings produced with the new cored wire are attractive for applica tions in many industrial sectors involving high temperatures.