roceofthecoatingisfinishedandnewγ-（feni）phaseisproducedwhentemperaturerisesto500oc.therefore，themi

crostructurechangingproceofthecoatingisamorphous→mixture→crystal；therareearthhasnoeffectonthemicrostructureofthecoating，whileitcanincreasethesiccontentinthedeposits.sodiumtungstateandcitricacidconcentratiointhebathhavenoeffectsonthemicrostructureofthecomposite，howevertheyhavecoiderableeffectsonthesurfacemorphologiesofthecoatings.thecoatingswithfinecrystalandsmoothsurfacewillbeobtainedwhensodiumtungstateconcentrationis90~150g/landcitricacidconcentrationis150~170g/l.thephohoruscontentinthecompositeisadecisivefactorthatenablesthecoatingtochangeintoamorphousstate.
theresistancetooxidationathightemperatureofthemultifunctionalelectrodepositedre-ni-w-p-siccompositesisinvestigated.theresultsshowthatduringhightemperatureoxidationtherelatiohipbetweentheoxidizedfilmweightofpureni,ni-w-p,ni-w-p-sicorre-ni-w-p-siccoatingandtheoxidationtimeisamixedcurve,i.e.itisaroximatelyalinearrelatiohipwhentheoxidationtimeislethan60miwhileitisapowerfunctionrelatiohipwhentheoxidationtimeisover60mi.theoxidationrateorderofthefourcoatingsisni>ni-w-p>ni-w-p-sic>re-ni-w-p-sic.theoxidizedfilmweightofni-w-p,ni-w-p-sicorre-ni-w-p-siccoatingincreasesexponentiallywithariseinoxidationtemperature.thehightemperature-oxidationresistanceofre-ni-w-p-siccompositecoatingis3~4timesthatofni-w-palloycoating.thecrosectionmorphologiesshowthatafterheat-treatmentat500octheni-w-pcoatingdiffusesintothematrix,andthereisno

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