1, the stainless steel telescopic door is deposited with other metal elements or strong attachments of different metal particles. In the moist warm environment, the liquid between the attachments and the stainless steel turns the two into a weak battery, thus triggering the electrochemical reaction, which causes the protective film to be damaged, and we call it electrochemical corrosion.

2、不锈钢伸缩门外表粘附着有机物汁液（如汤汁、唾液等），在有水氧情况下，构成有机酸，长时间则形成有机酸对金属表面的腐蚀。

2, the surface of the stainless steel expansion door adhered to the organic juice (such as soup, saliva, etc.), in the presence of water and oxygen, formed organic acids, for a long time the formation of organic acids on the corrosion of the metal surface.

3、在有污染的空气中（含有大量的硫化物、氧化物铜钟 一次性止血带 标志桩模具 钢丝轮 流水槽模具 防撞墙模具 检查井钢模具 不锈钢铸件 模锻件、氧化氢的大气），遇冷凝水，形成硝酸、醋酸液点，引起化学腐蚀。

3. In the polluted air (containing a large amount of sulphide, oxide, hydrogen oxide atmosphere), condense water, forming nitric acid, acetic acid liquid point, causing chemical corrosion.

4、不锈钢伸缩门外表粘附含有酸、碱、盐类物质（如装修墙壁的碱水、石灰水喷测）引起局部腐蚀。