环氧树脂/重结晶碳化硅复合材料的抗腐蚀性能

Corrosion Resistance of Epoxy Resin/recrystallized Silicon Carbide Composite

以E44型环氧树脂(EP)为填充材料,制备了环氧树脂填充重结晶碳化硅(EP/RSiC)复合材料。通过对表面形貌、动态电位极化曲线、电化学阻抗图谱、腐蚀速率进行分析,研究了EP/RSiC在静态室温条件下2 mol/L H2SO4溶液和4 mol/L NaOH溶液中的腐蚀行为。结果表明:EP/RSiC复合材料结构致密,具有较低的腐蚀电流密度和较高的自腐蚀电位,抗腐蚀性良好。EP/RSiC复合材料的腐蚀由SiC的活性溶解造成,因此EP/RSiC复合材料更容易受到碱性溶液的腐蚀,并且其腐蚀行为受电荷传递控制;EP/RSiC复合材料的腐蚀速率随EP填充量的增加而减少。15%(体积分数)EP/RSiC的抗腐蚀性最佳,在2 mol/L H2SO4溶液中的腐蚀速率为152 mg/(dm2·d),在4 mol/L NaOH溶液中的腐蚀速率为310 mg/(dm2·d),与RSiC相比其腐蚀保护效率分别达到90.5%和93.7%。

Resin-filled recrystallized silicon carbide(EP/RSiC)composites with good corrosion resistance were prepared by using E44 epoxy resin as the filling material.The corrosion behavior of EP/RSiC composites in 2 mol/L H2SO4solution and 4 mol/L NaOH solution at room temperature was studied by means of weight loss measurement,potentiodynamic polarization curves measurement,electrochemical impedance spectroscopy as well as corrosion morphology characterization.The results demonstrated that the EP/RSiC composites had a dense structure,low corrosion current density and high free-corrosion potential,and good corrosion resistance.Electrochemical tests suggested that the corrosion of EP/RSiC composites was caused by the active dissolution of silicon carbide.Therefore,EP/RSiC composites were more susceptible to corrosion by alkaline solutions,and their corrosion behavior was controlled by charge transfer.The corrosion rate decreased as the amount of epoxy resin filler increased,among others,the EP/RSiC with 15%(volume fraction)epoxy resin had the best corrosion resistance,namely its corrosion rate was 152 mg/(dm2·d)in 2 mol/L H2SO4solution,while 310 mg/(dm2·d)in 4 mol/L NaOH solution respectively.Which demonstrates that the EP/RSiC with 15%epoxy resin exhibits a corrosion protection efficiency about 90.5%regarding to the plain RSiC without the addition of epoxy resin.