GB/T 39495-2020金属及其他无机覆盖层铝及铝合金无铬化学转化膜标准
英文:Metallic and other inorganic coatings—Chromate-free chemical conversion coatings on allumion and its alloys GB/T 3949...
英文:Metallic and other inorganic coatings—Chromate-free chemical conversion coatings on allumion and its alloys GB/T 3949...