Laser Cladding Ni/WC Composite Coating And Applied Research In Laser Combination Additive Manufacturing WC-Ni Corrugated Roller

In the process of service,the corrugated roller stands high load,high temperature and the impacting action of impurity and hard minerals in the corrugating medium,corrugated roller's tooth are prone to severe wear,and finally caused the failure of corrugated roller.The wear is the main failure form of corrugated roller,therefore,improving the wear resistance of corrugated roller is the key to extend its service life.The laser combination additive manufacturing technology is a new method of material surface modification,it can combinate different functional materials to form a high quality metallurgical bonding.In order to improve the wear resistance of corrugated roller,a kind of Nickel-based WC composite powder is designed,and investigating the laser combination additive manufacturing process.Nickel base alloy powder exhibits superior antioxidant,corrosion resistance,and wettability with WC particles.But the nickel alloy can not meet the high wear resistance of corrugated roller,adding WC particles in the nickel alloy will significantly improve the wear resistance of coating.The Nickel-based WC composite coatings without cracks were successfully prepared by laser cladding on the 45 medium carbon steel under optimum parameters,The mass fraction of WC particle in optimal coating could reach as high as 80%.The cross-section morphologies,elemental compositions and phases of the nickel-based WC composite coatings were analyzed by scanning electron microscopy,energy dispersive spectrometry and X-ray diffraction,respectively.The hardness and wear resistance of composite coatings were also examined by rockwell hardness tester and high temperature wear test machine.The results show that the structure of the coatings is homogeneous,dense and non-crack,the WC particles distributed homogeneously in the composite coatings.In the cladding process,the nickel-based alloy and WC can produce plenty of carbides which had a function of dispersion strengthening.Special interactive structure formed between WC particles and nickle-based alloy increases the bonding strength.The composite coating contains WC?W2C??-Ni?M7C3 and Cr23C6 phases,which are beneficial to increase the hardness and wear resistance of the coatings.On the basis of good surface morphology and structure of composite coatings,the applications of the composite coatings prepared by the laser combination additive manufacturing under corrugated roller were studied.The research result shows that the tooth of corrugated roller fabricated by laser combination additive manufacturing have good abrasion resistance and combination with the steel base.This technology could also be used to repair corrugated roller.