Hi Reza
to the Surface Engineering Forum.
I would stress the word GRIT when talking of blasting materials for surface preparation for thermal spray. Shot or bead blasting does not produce a suitable texture or "sharp etch" required for good bonding.
Angular chilled iron and aluminium oxide based grits are recommended and are probably the most widely used abrasives for thermal spray. For some special applications more exotic materials like silicon carbide are sometimes preferred. The use of cheaper abrasive grits like copper slag are used for zinc anti-corrosion coatings, but I would not recommend them for other thermal spray coatings, unless they are used to do the brunt of the cleaning, prior to final blasting with better quality abrasive grits.