Study On Corrosion And Antifouling Properties Of Laser Cladding Copper Alloy

In order to solve the problem of corrosion and fouling of hull steel plates,seawater pipelines and other materials in the marine environment,laser cladding technology is used to prepare a corrosion-resistant and anti-fouling alloy cladding layer on the surface of steel.While meeting the low cost,it can also effectively improve the corrosion resistance and antifouling performance of the substrate.This paper uses the high-speed laser cladding technology to prepare a C1 copper alloy cladding with 70%copper content and a C2 nickel-copper alloy cladding with 20%copper content for comparison on the surface of Q235 steel substrate.The X-ray diffraction(XRD),scanning electron microscope(SEM)and energy spectrometer(EDS)were used to analyze the phase composition and micromorphology of the two alloy cladding samples;The micro-hardness value of the samples were measured with a micro Vickers hardness tester;The electrochemical corrosion resistance of the cladding layer was studied by using an electrochemical workstation;The inductively coupled plasma spectrometer(ICP)was used to determine the concentration of copper ions in the exudate,then the anti-marine fouling performance of the samples were analyzed.The experimental results show that the two alloy cladding layers have achieved good metallurgical bonding with the matrix Q235 steel.The surface of C1 alloy cladding layer with a copper content of 70%has no cracks,the quality of the cladding layer is better.Observing the surface morphology after aqua regia,it was found that Mo and Cr elements were enriched in the grain boundaries,and the grains interior were Cu-Ni solid solution.There are many cracks,holes,many large irregularly shaped copper-rich precipitates on the surface of C2 alloy cladding layer with a copper content of 20%.The polarization experiments show that the C1,C2,and cast red copper(ZCu)samples have shorter passivation platforms,which belong to the passive material system,and Q235 steel belongs to the active dissolving material system.Combined with the change of the open circuit potential with time,the seawater corrosion resistance of the samples is ranked as C1>ZCu>C2>Q235 steel.Galvanic corrosion experiments find that galvanic corrosion occurred in the samples of Cl and C2 cladding layers and Q235 steel,6061 aluminum alloy and TC4 titanium alloy.The galvanic corrosion current density with TC4 titanium alloy is relatively low,and the galvanic corrosion current density with Q235 steel and 6061 aluminum alloy is relatively higher.The copper ion release test showed that after the 10th day of C1,C2,and ZCu samples,the copper ion release rate could inhibit the growth of all marine organisms.On the 24th day,the copper ion release rate of the Cl copper alloy cladding layer sample continued to increase,and was higher than Copper ion exudation rate values for C2 and ZCu samples.