阳极氧化处理入门培训ppt课件

,阳极氧化入门培训,1,純鋁的特性,兩性金屬,化學性活潑易於空氣中生成氧化物,氧化鋁可阻止繼續氧化,鋁純度愈高膜層愈均勻,耐蝕性愈佳。對還原劑易起作用.但對氧化劑則有耐蝕功能.純鋁在濃硝酸下呈鈍態.比重輕,為地球表面存在最高之金屬,且表面處理形態多樣化,工業廣為應用.導電率約為銅的60%.熱傳導率為銅的1/2鐵的3倍.,2,鋁合金的分類,3,Definition,Anodizingisthesuccessfuldevelopmentandcontrolofanaturaloxidationprocessthatoccurswhenaluminumisexposedtotheatmosphere.Electricityandchemicalsareusedjointlytoproduceahard,transparentsurfacethatisintegralwithbaseAluminum.鋁於大氣環境下即會產生一層氧化皮膜.鋁底材接陽極電流於電解液中產生一層硬而透明的表面,此電化學反應稱之為”陽極處理”,4,Characteristics陽極處理的特性,Hard,comparabletoasapphire(藍寶石)Transparent,similartoglass(透明,接近玻璃)Insulativeandstatic-resistant(絕緣,防靜電)Widevarietyofcolorsandfinishes(顏色外觀多變)IntegralwithAluminumsurfaces,non-flaking(與鋁表面完全結合且不碎裂),5,PhysicalpropertyofAluminumanodizing陽極處理的物理性質,Porositydensity陽極孔密度6x1010/cm2Coefficientofthermalconductivity0.16cal/cm.sec.熱傳導係數Electricalresistance電阻1213M-cmPotentialresistance耐電壓400VFilmthickness膜厚520m(normal),30100m(hardanodizing)Porosityratio孔隙率2030%Hardness硬度200250Hv(normal),400450Hv(hardanodizing)Density密度3.18g/cm3(20)Heatresistance耐熱溫度300coefficientofthermalexpansion熱膨脹係數4.5x10-6M/,6,陽極處理的應用,Increasedcorrosionresistance增加耐蝕性Increasedwearabrasionresistance增加耐磨耗性Improvedbaseforpaintadhesion改善底材與塗膜之密著Providesanelectricallynon-conductivesurface提供絕緣表面Providesthermalinsulation隔熱Protectspolishedandothermechanicallyfinishedsurfaces保護拋光及機械加工過的表面Improvesappearanceofthesubstrate改善外觀,7,Howtoformtheporousfilm?陽極膜的生成,nm,8,Differencebetweentheanodicoxidationandtheplating陽極處理與電鍍的差異,9,Anodizingstructure陽極膜的結構,10,Anodizingprocess陽極處理的流程,Pretreatment(前處理)TheAluminumsurfaceisfirstcleanedthenchemicallytreated.Etching、chemicalpolishresultsinadesirousappearance.包含清潔脫脂、蝕刻、化學拋光等Anodizing(陽極處理)Oncethesurfaceisprepared,theanodicfilmisbuilt.PostTreatment(後處理)Theporousanodicfilmcanbecoloredinthisstage.Sealing(封孔)Manyofthecolorsarefade-resistant.Sealingtheanodicfilmnormallyconsistsofahotwaterbaththatbasicallyswellstheporesshut.,11,12,13,14,15,Sealingprocess封孔流程,16,ReactionFormula反應方程式,Astheanodereaction2Al=2Al3+6e2H2O=O2+4H+6e4Al3+3O2=2Al2O3+12eAsthecathodereaction2H+2e-=H2,17,SurfacePreparation前加工製程,MechanicalPolish機械拋光Scrubbing刷磨(如拉髮線等)Sandblasting噴砂ChemicalPolish化學拋光Etching蝕刻、霧化,18,MilSpec8625FTypeIAConventionalcoatingsproducedfromchromicacidbathThickness0.5-7.6TypeIBLowvoltagechromicacidanodizing(20volts)Usedfor7xxxseriesalloys0.5-7.6TypeIIConventionalcoatingsproducedfromsulfuricacidbath1.8-25.4TypeIIIHardcoat(Uniformanodiccoatings)12.7-115Class1NondyedClass2Dyed,19,检验方法及不良原因,烧伤指零件与阴极接触或零件彼此之间接触发生短路所造成.粉化指零件表面的氧化膜呈粉状，用手一擦即掉沫.水渍指零件烘干前水未吹干，烘干后留下的痕迹.黑斑氧化后没有清洗干净就