This unification establishes the methods for the approval of phospho-chromation processes, for decorative and protective purposes as an end in itself or as a painting base, on objects made of aluminum and its alloys. 2 The approval criterion means the testing of normal samples treated with the process to be approved, to verify that they satisfy the minimum quality requirements. The samples are chosen to ensure the overall effectiveness of the process.
UNI 4718-1961 history
0000 UNI 9921-1992
1961UNI 4718-1961 Surface treatment of metal materials. Phosphorus in aluminum and its alloys. Chromate treatment. Process method approval