车辆装备涂层局部微小破损对防护性能的影响研究

Research on the Effect of Local Minor Damage of Vehicle Equipment Coating on Protection Performance

目的探究车辆装备有机涂层在微小破损之后性能的变化情况,并通过完好涂层防护能力的对比分析,间接预测微小破损涂层的服役寿命。方法利用某型现役装备涂层作为试验样本,进行综合环境下的循环加速腐蚀试验,最后利用EIS分析实验数据,分析两者防护性能的差别。结果完好涂层与破损涂层的防护性能均出现了大幅度的下降,两者在经过10个周期的腐蚀试验之后,都失去了防护能力,出现了大面积锈迹。完好涂层的低频阻抗模值|Z|0.1 Hz在试验初期处于1010Ω·cm2数量级,最后下降到106Ω·cm2以下;初始状态破损涂层的低频阻抗模值|Z|0.1 Hz为1.2×105Ω·cm2,9个腐蚀周期之后下降至5.7×103Ω·cm2,下降了2个数量级。结论破损涂层在腐蚀初期更多地表现出电容性质,其试验初期的防护能力大约相当于完好涂层经历6~7次循环试验之后的防护能力,破损部分随着腐蚀周期的变化呈现“钝化—溶解—再钝化—再溶解”的周期性变化规律。

To explore the changes in the performance of organic coatings on military vehicles after minor breakage and indirectly predict the service life of micro-damaged coatings through the comparative analysis of the protective ability of intact coatings,this paper uses a certain type of active equipment coating as a test sample to carry out the cyclic accelerated corrosion test under the integrated environment.Finally,EIS is used to analyze the experimental data on the difference of the protective performance.As a result,both the protective properties of the intact coating and the damaged coating show a significant drop.Both of them lose their protective ability after 10 cycles of corrosion test,and a large area of rust appears.The low-frequency impedance modulus|Z|0.1 Hz of the intact coating is in the order of 1010Ω·cm2 at the beginning of the test and finally falls below 106Ω·cm2.The low-frequency impedance modulus of the damaged coating|Z|0.1 Hz is 1.2×105Ω·cm2 for the initial state,and after the 9 corroding cycles to 5.7×103Ω·cm2,it is decreased by 2 orders of magnitude.Damaged coating exhibits more capacitive properties at the beginning of the corrosion.Its initial protective effect is approximately equivalent to the 6~7th cycle test of the intact coating.The damaged part exhibits the periodic variation of“passivation-dissolution-repassivation-redissolution”.