炮弹钢磷化膜的制备及耐腐蚀性研究

Preparation and Corrosion Resistance of Phosphating Film for Projectile Steel

为了减小海军炮弹受到环境腐蚀的影响,对炮弹表面进行磷化处理以提高其耐蚀性能。磷化具有易操作、低成本、高效率等优点。以炮弹钢试样为研究基材,通过单因素试验与正交试验优选了磷化液的最优配方,以硫酸铜点滴试验评价了磷化膜耐蚀性,分析了未磷化与磷化后炮弹钢试样的极化曲线,观察了磷化膜的金相组织结构,对炮弹钢表面磷化膜进行了盐雾试验。结果表明:磷化处理后的炮弹钢试样耐蚀性比未磷化的炮弹钢试样有了明显提高;磷化膜的晶体多数呈棒状结构,且纵横交错排布堆集致密,空隙较少,膜层可有效隔绝基体与外部环境直接接触;炮弹钢表面磷化膜经过80 h盐雾试验,其表面未见锈蚀。

In order to reduce the effect of environment corrosion on the projectile steel,phosphating treatment was conducted. The projectile steel sample was taken as the research substrate,and the optimal formulation of the phosphating solution was determined by single factor experiment and orthogonal experiment. Moreover,the corrosion resistance of the phosphating film was evaluated by copper sulfate drop test. The polarization curves of projectile steel samples without phosphating and with phosphating were analyzed. Furthermore,the metallographic structure of the phosphate film was observed and a salt spray test was carried out on the phosphating film of the projectile steel. Results showed that the corrosion resistance of the projectile steel sample after phosphating was significantly improved;most of the phosphating film had a rod-like crystal structure,and the vertical and horizontal staggered arrangement was dense and had few voids;the film layer could effectively prevent the substrate from directly contacting the external environment;no rust was observed when the phosphating film on the surface of the projectile steel was subjected to a salt spray test for 80 hours.