Effect of Grit Blasting on Substrate Roughness and Coating Adhesion

Journal Article · Fri Sep 01 04:00:00 EDT 2006 · Journal of Thermal Spray Technology

DOI:https://doi.org/10.1361/105996306X124347· OSTI ID:912340

Varacalle, Dominic; Guillen, Donna; Deason, Doug; Rhodaberger, William; Sampson, Elliott

Statistically designed experiments were performed to compare the surface roughnesses produced by grit blasting A36/1020 steel with different abrasives. Grit blast media, blast pressure, and working distance were varied using a Box-type statistical design of experiment (SDE) approach. The surface textures produced by four metal grits (HG16, HG18, HG25, and HG40) and three conventional grits (copper slag, coal slag, and chilled iron) were compared. Substrate roughness was measured using surface profilometry and correlated with operating parameters. The HG16 grit produced the highest surface roughness of all the grits tested. Aluminum and zinc-aluminum coatings were deposited on the grit-blasted substrates using a Twin-Wire Electric Arc (TWEA) process. Bond strength of the coatings was measured with a portable adhesion tester in accordance with ASTM standard D4541. The coatings on substrates roughened with steel grit exhibit superior bond strength to those on substrates prepared with conventional grit. For aluminum coatings sprayed onto surfaces prepared with the HG16 grit, the bond strength was most influenced by current, spray distance, and spray gun pressure (in that order). The highest bond strength for the zinc-aluminum coatings was attained on surfaces prepared using the metal grits.

• Research Organization: Idaho National Laboratory (INL)
• Sponsoring Organization: DOE - NE
• DOE Contract Number: AC07-99ID13727
• OSTI ID: 912340
• Report Number(s): INL/JOU-05-00633
• Journal Information: Journal of Thermal Spray Technology, Journal Name: Journal of Thermal Spray Technology Journal Issue: 3 Vol. 15
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ABRASIVES
ADHESION
ALUMINIUM
COAL
COATINGS
COPPER
DESIGN
ELECTRIC ARCS
EXPLOSIVE FRACTURING
IRON
ROUGHNESS
STEELS
SUBSTRATES
grit blasting
surface roughness