Home / Standards / GB/T 39432-2020 GB/T 39432-2020 Active Non-destructive testing—Ultrasonic testing—Specification for step wedge calibration block 无损检测 超声检测 阶梯试块 Standard Type GBT ICS 19.100 CCS J04 Status 现行 Issue Date 2020-11-19 Implementation 2021-06-01 Responsible Dept 国家标准委 Drafting Unit 国家标准委