| Beryllium is widely used in aerospace parts and nuclear reactors with its advantages of high hardness,low density and high thermal neutron scattering and physical stability.In the instrument part,the application performance of beryllium can be improved by using different film layer beryllium.In order to get better beryllium materials,this paper by studying the different coating beryllium material（anode oxidation film and chemical passivation film layer insulation,chemical nickel plating film layer）in atmospheric corrosion experiment,the corrosion resistant experiments,wear-resisting performance test,the appearance,quality,size,surface roughness,bonding strength,etc.,to assess the performance of various membrane layer.At the same time,the micro-arc oxidation of beryllium is studied and a set of stable and reliable microarc oxidation treatment technology is summarized.The hardness test results showed that the hardness of electroless nickel coating（513.6HV）was greater than that of chemical passivating film（329.7 HV）,and the hardness of the anodized film（194.1 HV）was the smallest.The adhesion and tensile strength of the electroless nickel coating（tensile strength was greater than 0.18 MPa）on the beryllium matrix were the largest.In addition,the adhesion and tensile strength of beryllium in anodized film layer were the least.When tensile strength was greater than 0.13 MPa,there was a phenomenon of detachment of beryllium and beryllium materials in the chemical passivation film.Beryllium material with different membrane layer in atmosphere environment corrosion situation of studies have shown that the chemical plating nickel film layer（corrosion weightlessness S=0.12 mg/cm2）and chemical passivation film layer（corrosion weightlessness S=-0.2 mg/cm2）can better protect the beryllium substrate,and the anode oxidation film layer（corrosion weightlessness S=0.24 mg/cm2）to protect the beryllium substrate was poor.The coating of the electroless nickel film has the highest coverage of the beryllium matrix,and the surface layer is corroded first,which is more protective to the matrix.The corrosion results of beryllium materials in different film layers in the salt spray environment showed that the corrosion weight of the electroless nickel coating（S=0.38mg/cm2）was heavier,but concentrated on the surface.The chemical passivation film（S=0.04 mg/cm2）can better protect the beryllium matrix.However,the anodic oxide film（S=-0.28 mg/cm2）was less protective of the beryllium matrix.The anodic oxide film layer is caused by the oxidation film of the beryllium oxide and the structure of the beryllium oxide,which causes the film layer to crack,and the overall corrosion resistance is the worst.The beryllium material with different protective film layers was eroded by soaking in 0.1mol/L HCl,NaCl and NaOH.And the mass fraction of 3.5%NaCl aqueous solution（electrochemical polarization under the chemical plating nickel polarization resistance of9868?·cm2,polarization resistance of 14605?·cm2,anodic oxidation,polarization resistance of 7275?·cm2）and 5%（NH4）2SO4 aqueous solution（electrochemical polarization under the chemical plating nickel polarization resistance of chemical passivation 15788?·cm2,polarization resistance of 14605?·cm2,anodic oxidation polarization resistance of 6621?·cm2）in the study of electrochemical corrosion.The corrosion resistance of the electroless nickel beryllium film layer is the best,because the film layer is evenly distributed and completely protects the beryllium matrix.Uneven chemical passivation membrane layer of beryllium materials generated is not complete,and the passivation membrane beryllium oxide is not stable,poor corrosion resistance,but the electrochemical corrosion of beryllium oxide product can protect the beryllium substrate,thereby reducing subsequent corrosion,the polarization resistance increased.The hardness of the membrane layer was significantly increased after the microarc oxidation of beryllium base material,and the hardness could reach 984.1HV.The study on the micro-arc oxidation process of beryllium,the optimal solution of the electrolyte components is 6 g/L sodium silicate,1.5 g/L boric acid,0.5 g/L hydroxide and 6 ml/L hydrogen peroxide,and the micro-arc oxidation voltage is 500 V.Each electrolyte component has different influence on the oxidized ceramic film of enamel.Sodium silicate as the main filming agent has the greatest effect on the formation of the oxidized film layer of the casket.The second micro-arc oxidation voltage and hydrogen peroxide concentration promote the film.The effect was secondary,and boric acid and potassium hydroxide acted simultaneously at a certain ratio（3:1）to promote the formation of oxide films on the coffin. |
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