{HEAD ~ The iron} contains {TAIL ~ alloying elements} that enhance the high temperature thermal fatigue and hot oxidation resistance in service 
contains
{ HEAD ~ The iron } contains { TAIL ~ alloying elements } that enhance the high temperature thermal fatigue and hot oxidation resistance in service
HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH