An Experimental Study On Inner Cladding Casting

With the development of industry, on the material properties of the proposed newrequirements, metal or alloy has been difficult to meet the social demand forcomprehensive performance of the material, so in recent years new composite materialsvalued in the world. Metal composite materials should have the "complementary effect"in the base metal properties at the same time, to make up for the inadequacy of their. Inthis paper, the experimental investigation was conducted on the effect of the coatingproperties of arc spraying parameters, a kind of inner cladding type casting method isintroduced, and the method for boundary cladding type casting and FeCrAl Al-Alcoating was prepared on Al-Al type casting, inner cladding type castings were analyzedand corrosion immersion test and Al-Al inner cladding type casting sectionmicrohardness, microstructure observation of FeCrAl, inner cladding type castingmicrostructures were observed, test analysis of FeCrAl inner cladding type castingsection microhardness and FeCrAl inner cladding type casting heat treatmentexperiment.Through the experimental study on the boundary of a coated casting can beobtained as follows:（1） the inner cladding type circle cladding type casting and FeCrAl has anintermediate layer of Al-Al within the field covered with casting was prepared bycasting, has the feasibility that within a circle cladding type casting.（2） when the wire when the voltage is15V, the surface roughness of the coating issmaller, and the wire feeding voltage increases the surface roughness increases, coatingporosity or larger space, and gradually decreases with increasing porosity or wirevoltage gap; when the spray voltage is27.9V, the rough surface coating is larger, andwith the spray voltage increases the surface roughness decreases, coating porosity ormore clearances, and with the increase of spray voltage, coating pores or intersticesgradually reduce.（3） based on the Al-Al inner cladding type castings were observed by SEM andEDS spectrum analysis. The results show that, the matrix Al and arc sprayed Al coatingand no boundaries and pores are less obvious, combination is metallurgicalcombination.（4） soaking experiments of arc spraying Al, Al and Al-Al matrix inner cladding type casting, and the cross section of Al-Al inner cladding type castings have beenmicrohardness test. Arc sprayed Al layer, Al matrix by140h after immersion tests,stomata showed different degree becomes larger, but in the Al-Al community claddingtype casting by140h after immersion tests, stomatal changes little, Al-Al corrosionresistance coating casting industry has been greatly improved. The microhardness ofcoating casting along the interface towards the substrate Al direction gradually reduced,microhardness distribution of Al-Al inner cladding type casting is influenced by thecomposition effects of α-Al₂O₃phase（5） of coated FeCrAl castings were observed by SEM, EDS energy spectrumanalysis, microhardness test and heat treatment. The results show that, interdiffusionbetween the coating type casting casting elements. The microhardness of coating castingby the FeCrAl layer250HV gradually transition to the base Al40HV. Heat treatmentexperiments show that, with the temperature of heat treatment by Al elements increased,the middle transition layer gradually enriched, oxidation is becoming more and moreserious, and the intermediate oxide transition layer thickness gradually become larger.