采用体式显微镜和铜加速乙酸盐雾试验、湿热试验、耐水性试验等方法研究了汽车铝轮毂材料表面高分子粉末涂层的耐蚀性能。结果表明, 轮毂样品经240 h铜加速乙酸盐雾试验(CASS试验)后划痕处边沿部分漆膜翘起且有脱落; 划痕边沿起泡数量增多, 最大单边腐蚀宽度约1.5 mm; 非划痕区域泡数量增多, 直径增大, 最大起泡直径约2 mm。铝轮毂试样和试片经过240 h湿热试验和耐水性试验后, 样品表面无起泡、剥落、起皱等现象, 漆膜附着力为0级, 硬度保持为3 H。温热试验后光泽保持率为98.6%, 色差为0.17; 耐水性试验后光泽保持率为87.9%, 色差为0.29。

The corrosion behavior of aluminum hub with organic coating was investigated by metallographic microscopy, CASS test, wet-heat test and immersion water test. The results showed that the partial coating near the artificial defect for hub sample turned off and breaked off, the bubbles near the artificial defect became more and more, the widest corrosion distance was 1.5 mm. The bubbles in the area without the artificial defect also became more. The diameter for the bubble became bigger. The biggest diameter was 2.0 mm. The hub sample after 240 h wet-heat test showed no bubles and crinkles in the surface. The coherence strength for the coating was 0 level, the rigidity was 3 H. The glossiness was 98.6%, the chromatic aberration was 0.17. The hub sample after 240 h immersion test showed no bubles and crinkles in the surface, the coherence strength for the coating was 0 level, the glossiness was 3 H, the glossiness was 87.9%, the chromatic aberration was 0.29.