Home / Standards / GB/T 31204-2014 GB/T 31204-2014 Active Carbon steel investment casting 熔模铸造碳钢件 Standard Type GBT ICS 77.140.80 CCS J31 Status 现行 Issue Date 2014-09-03 Implementation 2015-06-01 Responsible Dept 国家标准委 Drafting Unit N/A