摘要
某超临界燃煤发电机组高压蒸汽管螺栓硬度超过标准要求。为此,对2根硬度超标螺栓进行了力学性能检验、金相检验和能谱分析。结果表明:螺栓中存在明显的混晶及带状组织;奥氏体晶界有未溶Ti颗粒、碳化物和金属间化合物;这些缺陷导致螺栓材料局部硬化,最终造成螺栓硬度超过标准要求。
Hardness of high-pressure steam pipe bolts used in a supercritical coal-fired power generation unit exceeded the requirement in the standard.For this reason,mechanical property survey,metallographic examination and energy spectrum analysis were performed on two pieces of bolts.The results indicated that the bolts exhibited evident mixed crystal and bonded structure,as well as undissolved titanium and intermetallic compounds at the austenite grain boundaries.These defects cause local hardening of the material,ultimately resulting in inadequate bolt hardness.
作者
陈强
CHEN Qiang(Anhui Special Equipment Testing Institute,Hefei 230031,Anhui,China)
出处
《热处理》
2025年第4期56-58,共3页
Heat Treatment
关键词
螺栓
硬度超标
混晶
带状组织
bolt
hardness exceeding
mixed crystal
banded structure
