As {HEAD ~ a method} of spraying aluminum or {TAIL ~ aluminum alloy}, there is arc spraying and plasma spraying 
of spraying
As { HEAD ~ a method } of spraying aluminum or { TAIL ~ aluminum alloy } , there is arc spraying and plasma spraying
OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH