摘要
对锻造后的RH12模具钢锻圆超声波探伤检测时发现部分坯料心部存在缺陷,且不同支锻圆缺陷长度有所差异。为查明缺陷原因,对有缺陷坯料取样分析,进行成分检测,热酸洗检验,利用金相显微镜进行组织观察。结果发现,密集粗大的一次碳化物是引起锻造后心部探伤缺陷的主要原因。冶炼时采用合理工艺参数是防止产生一次碳化物的主要手段,一旦出现一次碳化物,通过增大锻比(或采用镦拔处理)可改善钢材心部质量。措施实施后,RH12模具钢锻圆心部缺陷明显改善。
When inspected with ultrasonic, some defects are discovered in the core of part of blanks of forged round steel of RH12 die steel, and their lengths is different in different forged round steel. To find the reason, the defect blanks are sampled and analyzed： composition detection, hot annealing check, structure observation with metallographic microscope. It is discovered that the dense and bulky primary carbide is the main reason. Adopting reasonable process parameters in smelting is the main way to prevent primary carbide, and once it occurs the steels core quality can still be improved with increase forging ratio （or adopting upsetting and stretching process）. After the measures carried out, the defects are distinguished improved.
出处
《河北冶金》
2016年第9期58-60,共3页
Hebei Metallurgy
关键词
模具钢
锻造
超声波探伤
缺陷
一次碳化物
die steel
forge
ultrasonic inspection
defect
primary carbide
