高温耐磨粘结铜除铜工艺研究

目的获得经济且环境友好型化学溶解高温耐磨粘结铜的工艺。方法采用正交实验获得化学溶解除铜的最佳工艺参数,利用电化学手段测试铜及炮管基体在两种溶液体系最优配方中的E-t曲线和极化曲线,通过连续失重法分析铜在腐蚀溶液中的腐蚀溶解规律,并观察溶解后的表面形貌。结果化学溶解除铜工艺最优配方分别为过氧化氢-柠檬酸(H2O2(质量分数为0.8%)+C6H8O7(质量浓度为6 g/L)+温度θ为30℃+pH值为10)、溴酸钾-柠檬酸(KBrO3(质量浓度为30 g/L)+C6H8O7(质量浓度为30 g/L)+温度为30℃+pH值为10)。腐蚀溶解初始阶段,铜基体表面氧化膜逐渐溶解破坏,腐蚀电位变负,溶解速率加快,随后铜基体裸露,进入稳定溶解过程,反应速率逐渐趋于稳定。在溴酸钾-柠檬酸体系中铜的自腐蚀电流密度比过氧化氢-柠檬酸体系中高2个数量极,表现出更强的阳极活化能力和腐蚀溶解速度。结论铜在两种溶液体系中表现出快速稳定的溶解速度,炮管基体的腐蚀速率比铜小2~3个数量级,具有良好的耐蚀能力。

Research on Removal Technology of Bonded Copper on the Wear-resistant and Heat-resistant Surface

Objective To obtain the economical and environment friendly chemical dissolution process of wear-resistant bonded copper. Methods The optimized chemical dissolution processes were obtained from a series of orthogonal experiment. Corrosion dissolution rule and electrochemical behavior of copper and artillery barrel in chemical solutions were investigated using the continuous weight loss method,polarization curve and E-t curve. The morphology of the copper in the corrosion process was observed as well. Results The chemical dissolution processes were hydrogen peroxide-citric acid system—H2O2（ 0.8%） ＋C6H8O7（ 6 g/L） ＋θ（ 30℃） ＋ pH（ 10）,and potassium bromate-citric acid system—KBrO3（ 30 g/L） ＋ C6H8O7（ 30 g/L） ＋ θ（ 30 ℃） ＋ pH（ 10）,respectively. In the electrochemical test,the oxidation film of copper was gradually dissolved during the initial period,then the corrosion potential became negative with the increase of the dissolution rate. With the extension of time,copper matrix was exposed and entered the stable dissolution process and the dissolution rate tended to be stable. The corrosion current density derived from the polarization curve of the copper in potassium bromate-citric acid solution was two orders of magnitude greater than that in the hydrogen peroxide-citric acid solution,suggesting a much stronger ability of anodic activation. Conclusion Copper exhibited fast and stable dissolution rate,and the current density of artillery barrel was 2 ～ 3 orders of magnitude lower than that of the copper in both chemical solutions,suggesting excellent anti-corrosion performance.