Aluminum alloy surface blackening treatment method

An aluminum alloy surface blackening treatment method belongs to the technical field of metal surface treatment and comprises four steps of surface cleaning, surface activation, blackening liquid dipping and heat treatment. Through a simple blackening treatment process, a blackened film layer with good corrosion resistance and strong adhesive force is obtained on the surface of the aluminum alloy, in a corrosion resistance test, after a drop of a 5wt% sodium hydroxide aqueous solution is dripped on the film layer with the blackened surface, the time for generating bubbles is 94-101 seconds, the time for exposing matrix metal is 208-212 seconds, and in an adhesive force test, the film layer with the blackened surface has no bubbles. And when the film layer falls off or is broken, the steel balls are impacted for 109-116 times. 一种铝合金表面发黑处理方法，属于金属表面处理技术领域，包括表面清洗，表面活化，发黑液浸渍，热处理四个步骤；本发明通过简单的发黑处理工艺，在铝合金表面得到耐腐蚀性好，附着力强的发黑膜层，耐腐蚀性测试中，表面发黑的膜层上滴一滴5wt%的氢氧化钠水溶液后，有气泡冒出的时间为94~101秒，基体金属暴露的时间为208~212秒，附着力测试中，膜层脱落或破碎时钢球撞击的次数为10