Study On Corrosion Behavior Of Three Copper Alloys

Copper alloys are widely used in the field of marine engineering,and it is of great scientific and engineering significance to carry out research on the corrosion behavior and corrosion mechanism of copper alloys.In this paper,electrochemical corrosion,neutral salt spray corrosion and ultrasonic cavitation-electrochemical corrosion experiments were systematically studied in 3.5 wt%Na Cl solution of three materials,BFe30-1-1 and high-manganese aluminum bronze,and the corrosion resistance of the three copper alloys was compared by using electrochemical workstation,cavitation testing machine,circulating corrosion salt spray chamber,field emission scanning electron microscopy,energy spectrometer and X-ray diffractometer.The main experimental results of the full text are as follows:（1）In the electrochemical corrosion experiment,the corrosion resistance of three copper alloys:B30 alloy>B10 alloy>aluminum bronze.After polarization,aluminum bronze has a large number of granular corrosion products on the surface,and the products may be Mn O₂,Fe₂O₃,Cu₂O and other oxides;The surface of B10 and B30 alloys is relatively flat,and a small number of corrosive holes appear.Electrochemical impedance spectroscopy showed that B30 alloy had large arc resistance and good corrosion resistance.Followed by B10 alloy,aluminum bronze has small arc resistance and poor corrosion resistance.（2）In the neutral salt spray corrosion experiment,the corrosion rates of three copper alloys are:aluminum bronze>B10 alloy>B30 alloy.The four-square granular corrosion products on the surface of aluminum bronze may be Al₂O₃,Mn O₂,Fe₂O₃,Cu₂O and other oxides;The surface product of B10 alloy is triangular or prismatic,and the surface is the oxide of Cu,Ni;The surface corrosion products of B30 alloy are lumpy and lumpy,and the surface is all oxides of Cu and Ni.XRD showed that the corrosion products on the surfaces of aluminum bronze,B10 alloy and B30 alloy were all Cu₂（OH）₃Cl,and Cu₂O oxides were formed on the surfaces of all three alloys.（3）In the ultrasonic cavitation-electrochemical corrosion experiment,the corrosion weight loss of three copper alloys was:B10 alloy>B30 alloy>aluminum bronze.The surface of aluminum bronze is covered with a large number of granular and spherical corrosion products,and the corrosion products may be Mn O₂,Al₂O₃,Fe₂O₃,Cu₂O and other oxides.There are large diameter holes on the surface of B10 alloy,the degree of damage is serious,the elements at the corrosion pit are Cu and Ni in the matrix,and the oxide film layer on the surface may be damaged.The surface of B30 alloy is relatively flat,and Cu and Ni elements are enriched to form a passivation film on the surface.In the pore distribution data,the surface of aluminum bronze has many pores but is shallow.The surface pores of B10 alloy are large and deep,so the corrosion loss is high;B30 alloy has few pores and shallow surfaces.The results of electrochemical impedance spectroscopy show that B30 alloy has a large radius of arc resistance and good corrosion resistance.The capacitive arc resistance radius of B10 alloy in the low frequency region is smaller than that of aluminum bronze,so the corrosion resistance is worse than that of aluminum bronze.The corrosion resistance of aluminum bronze lies somewhere in between.