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