采用化学成分分析、金相组织检验和力学性能测定等方法对水冷壁管的爆管进行了综合分析。结果表明,爆口处的硬度明显高于基体的硬度;基体组织为铁素体+珠光体,没有明显球化现象,而爆口处的组织为铁素体+珠光体+贝氏体的亚温淬火组织。由此说明水冷壁管的爆裂主要是短时急剧过热造成材料的高温强度降低而开裂。

A comprehensive analysis which is based on chemical composition,optical microstructure,microhardness,tensile strength was made on the exfoliation cracking of water-cooling tube. The results showed that the hardness at the break was much higher than the hardness of matrix material. The matrix microstrucutre was made up of ferrite and pearlite which did not spheroidize obviously but the microstructure near break was made up of ferrite,pearlite and bainite which was the microstructure of sub-temperature quenching. The above results indicated that the exfoliation cracking of water-cooling tube was mainly caused by short-time sudden overheating which made the strength of the matrix material decrease dramasticaly and induced the exfoliation cracking of the tube.