Home / Standards / GB/T 13302-1991 GB/T 13302-1991 Active Steel--Determination of area content of graphite-micrographic method using diagrams 钢中石墨碳显微评定方法 Standard Type GBT ICS 77.040.30 CCS H24 Status 现行 Issue Date 1991-12-13 Implementation 1992-10-01 Responsible Dept 中国钢铁工业协会 Drafting Unit N/A