Home / Standards / GB/T 24177-2009 GB/T 24177-2009 Active Standard test methods for characterizing duplex grain sizes 双重晶粒度表征与测定方法 Standard Type GBT ICS 77.040.99 CCS H24 Status 现行 Issue Date 2009-06-25 Implementation 2010-04-01 Responsible Dept 中国钢铁工业协会 Drafting Unit 中国钢铁工业协会