Study On Microstructure And Properties Of Arc Cladding IN 718 Nickel-based Cladding Layer

With the speedy development of modern industry,the traditional and single metal materials gradually cannot accommodate the needs of modern industrialization.Marine equipment,aerospace,electric power systems,and oil pipelines have put forward higher requirements for the comprehensive performance of material usage.As a traditional low-cost material,the steel material is extensively used in various industries.Among them,low-alloy steel is widely used in actual production because of its low price and performance can meet the general use case.Inconel 718 high-temperature nickel-based alloy has become an indispensable material for various industries,such as petroleum,chemical,aerospace,energy,marine equipment,etc.Because of its excellent high temperature resistance,corrosion resistance and weldability characteristics,Marine equipment,etc.Its microstructure is a single austenite,the main phase composition is yphase matrix,γ’(Ni3Al,Ti),γ"(Ni3Nb),δ(Ni3Nb)etc.There are other precipitated phases,but the performance of Inconel 718 cladding layer such as wear resistance still needs to be improved,so how to solve the above problem is an urgent problem for modern industry.In order to solve this problem,a composite clad layer can be prepared by adding ceramic particles to Inconel 718 alloy which are close to its thermal expansion coefficient and can improve these properties,and using TIG arc cladding technology to combine the advantages of Inconel 718 and ceramic particles to improve the performance of Inconel 718 clad layer and achieve cost saving.The aim is to improve the performance of Inconel 71 8 cladding and achieve cost savings.In this paper,Inconel 718 cladding layer and Inconel 718-aTiB2/bB4C composite cladding layer were prepared on the surface of low alloy steel by using GTAW arc cladding technology by selecting TiB2 and B4C ceramic particles with similar coefficient of thermal expansion to Inconel 71 8,where a=5,10,15wt.%,B=5,1 0 wt.%,and the above cladding layers are recorded as Inconel 718 cladding layer,cladding layer A(5%TiB2),cladding layer B(10%TiB2),cladding layer C(15%TiB2),cladding layer D(5%B4C)and cladding layer E(10%B4C).To study the effect of TiB2 and B4C ceramic particles on the microstructure and properties of Inconel 718 alloy,OM,SEM,and EDS were used to analyze the microstructure and element distribution of Inconel 718 cladding layer A(5%TiB2),B(10%TiB2),C(15%TiB2),D(5%B4C)and E(10%B4C)which prepared with different content and types of TiB2 and B4C flux cored welding wires.The possible precipitates in the cladding layer were analyzed by XRD,combined with microhardness.To explore the influence of different types and contents of TiB2 and B4C ceramic particles on Inconel 718 alloy.Research has found that the interfaces of the prepared cladding layers are well bonded,and ceramic particles have a certain impact on the morphology of dendrites.At the bottom of the Inconel 718 cladding layer,there are thick columnar crystals,while in the middle of the composite cladding layer,there are mostly smaller dendrites.There is a different structure in the upper part of the composite cladding layer compared to the Inconel 718 cladding layer.Microhardness tests were conducted on each cladding layer,and it was found that the microhardness of cladding layer A(5%TiB2),cladding layer B(10%TiB2),cladding layer C(15%TiB2),cladding layer D(5%B4C)and cladding layer E(10%B4C)was significantly improved compared to the Inconel 718 cladding layer.Through EDS,it was found that there is significant segregation in the distribution of various elements,and the aggregation of elements may be precipitated phases.By using XRD to analyze the Inconel 718 cladding layer,cladding layer A(5%TiB2),cladding layer B(10%TiB2),cladding layer C(15%TiB2),cladding layer D(5%B4C),and cladding layer E(10%B4C).In addition,the friction and wear behavior and corrosion resistance of Inconel 718 cladding layer and Inconel 718-aTiB2/bB4C composite cladding layer were studied at room temperature.Through experiments,it was found that the addition of TiB2 and B4C ceramic particles can effectively improve the friction and wear resistance of Inconel 718.Under loads of 5N and 10N,the order of wear loss is basically consistent,and the main wear mechanisms are adhesive wear and abrasive wear.Through electrochemical workstation testing and evaluation of electrochemical performance,it can be found that adding appropriate amounts of TiB2 and B4C ceramic particles improves the corrosion resistance of the cladding layer.