Home / Standards / GB/T 13320-2025 GB/T 13320-2025 Upcoming Metellographic grading atlas and assessing method for steel die forgings 钢质模锻件金相组织评级图及评定方法 Standard Type GBT ICS 77.140.85 CCS J32 Status 即将实施 Issue Date 2025-12-31 Implementation 2026-07-01 Responsible Dept 国家标准委 Drafting Unit N/A