转向架用Q345C钢堆焊接头组织及盐雾腐蚀行为

Microstructure and salt spray corrosion behavior of bogie Q345C steel surfacing weld

通过金相组织分析、力学性能试验、极化曲线试验和盐雾腐蚀试验,对比研究Q345C母材及其堆焊接头组织、力学性能及耐蚀性能。结果表明,堆焊接头组织与母材相比具有一定的差异。母材的冲击韧性优于堆焊焊缝。在相同试验条件下,Q345C母材及其堆焊接头腐蚀初期表面均出现橘红色的锈层,随着试验的进行,锈层逐渐加深,绝大部分橘红色锈层变为黑褐色锈层腐蚀产物。堆焊焊缝的腐蚀倾向、腐蚀速度和腐蚀失重均低于母材,但相差不大,其耐蚀性能稍优于母材。

The microstructure, mechanical properlies and corrosion resistance of Q345C steel base metal and its surfacing weld were comparatively studied by microstructure analysis, basic mechanical properties test, polarization curve test and salt spray corrosion test.The results show that, there are some difference of the microstructure between Q345C steel base metM and its surfacing weld,and the impact toughness of the base metal is superior to surfacing weld.Under the same testing conditions,the surface of Q345C steel base metal and surfacing weld both generate orange nlst layer in the initial corrosion, along with tests, rust layer gradually changes color, becomes dark brown with dense tissue.The corrosion tendency,corrosion rate and corrosion weight loss of surfacing weld are lower than the Q345C steel base metal, but the difference is small, and the corrosion performance is slightly better than the base metal.