Influence Of Silane Treatment On The Surface Of Co-Cr Alloy About The Anticorrosive Property

Objective:Prepared dodecyltrimethoxysilane (DTMS) silane films on Co-Cr alloy surface with electrochemical technology, and researched the anticorrosive property of Co-Cr alloy after silanization in different silane hydrolysis pH and electrodeposition time.Material and Method:According to different silane hydrolysis PH (4～6) and electrodeposition time (10～20min),30 Co-Cr alloy specimens were randomly divided into nine experimental group and a control group. Prepared silane films on the specimens surface under-0.8 v critical deposition potential, and test Ecorr and Icorr of Co-Cr alloy specimens before and after silanization using the electrochemical corrosion method in simulated oral environment.Result:1.-Si-O-Si-,-OCH3-,-CH3-,-CH2-,-SiOH-,-SiOC-etc stretching vibration band of silane films can be observed in Raman spectrogram.The surface of silane films was dense and uniform in the graph of Scanning Electron Microscope.2 weeks later immersing in artificial saliva, there were a lot of black corrosion products and corrosion pit on the surface of Co-Cr alloy without silane films,but no change with silane films.2. Electrochemical corrosion analysis software shows, the differences of Ecorr and Icorr betweem experimental groups and control group were statistically significant (P<0.05) in the artificial saliva(pH5.7±0.1), Ecorr of the experimental groups were higher and Icorr were lower compared with the control group.3. When electrodeposition time was definite, Ecorr and Icorr were obviously different among different silane hydrolysis pH groups (P< 0.05), Ecorr pH4 group>pH5 group>pH6 group, Icorr pH4 group< pH5 group20min group>10min group, Icorr 15min group<20min group<10min group. 5. The differences of Ecorr and Icorr betweem experimental group (silane hydrolysis pH=4, electroplating time T=15min)and the other groups were statistically significant (P<0.05). Ecorr of the experimental group were higher and Icorr were lower compared with the other groups.Conclusion:1. Dense and uniform silane films could be deposited in Co-Cr alloy surface with electrochemical technology and improved greatly the anticorrosive property of Co-Cr alloy2. Silane hydrolysis pH and electrodeposition time had great influence on the anticorrosive property of Co-Cr alloy after silane treatment.The anticorrosive property of Co-Cr alloy was relatively better in the condition of silanization treatment(DTMS silane hydrolysis pH=4, electrodeposition time T=15min).