起重机用Q235钢耐蚀性的改进研究

Improvement of Corrosion Resistance of Hoisting Machinery Steel Q235

以冷喷涂技术,将机械球磨后的铬铝混合粉末喷涂在起重机械用Q235钢表面,并进行显微组织分析和盐雾腐蚀试验研究。结果表明:与未进行冷喷涂处理相比,表面制备铬铝复合涂层的试样在480 h盐雾腐蚀后的质量损失率降低了89.86%,试样表面的孔内腐蚀明显减少,腐蚀坑中氧含量从60.33%降至4.24%、氯含量从24.44%降至4.97%,耐蚀性得到显著改善。涂层冷喷涂的主要工艺参数为:载气温度(240±2)℃、载气压力(1.8±0.1)MPa、喷涂距离25 mm、送粉速度1.6 g/s。

The mechanical ball milled composite powder with Cr and A1 was sprayed on the surface of Q235 steel for hoisting machinery by the method of cold spraying with different process parameters, and the microstructure and salt-spray corrosion resistance of the sprayed steel were tested and analyzed. The results show that, compared with the sample without cold spraying, the mass loss rate of the Cr/A1 composite sprayed steel samples after salt-spray corrosion for 480 h is decreased by 89.86%, the hole corrosion on the surface of the sample apparently decrease, and the oxygen content in the corrosion pit decreases from 60.33% to 4.24%, the chlorine content from 24.44% to 4.97%, the corrosion resistance of Q235 steel improves greatly. The optimized process parameter of cold spraying is carrier gas temperature at （240±2） ℃, carrier pressure at （1.8±0.1） MPa, spraying distance for 25 ram, injecting speed at 1.6 g/s.