China Standard: GB 226­-1991 Etch Test for Macrostructure and Defect of Steels 

This national standard specifies testing of macrostructure and defect of steels with hot/cold etching methods and electric etching method. 

This national standard is applicable to test of macrostructure and defect of steels. If test is carried out for arbitration without any special specification in technical conditions, hot etching method shall be followed as standard.