ZG40Cr25Ni20炉管服役后断裂韧性试验分析及断口微观形貌研究

摘要

将断裂力学原理应用到炉管寿命预测中.利用MTS810试验机,对服役3万h的炉管和未服役炉管的断裂韧性进行了试验分析,并利用扫描电镜进行了断口的形貌分析.研究结果表明:服役后炉管的断裂韧性与未服役炉管相比显著下降,抵抗裂纹扩展能力减弱;服役后的炉管断裂面没有裂纹稳态扩展区和宏观塑形变形,对应于断裂韧性的下降,断裂面微观形貌呈典型的脆性断裂特征.%According to the principle of fracture mechanics, the fracture toughness of the furnace tube after 30000 hours service and new furnace tube were tested with the MTS810 tester.The microstructure of fracture surface were analyzed by the SEM.The results show that the fracture toughness of the furnace tube after service gets decreased greatly compared with that of the new furnace tube.The microstructure of fracture surface of the furnace tube changes significantly corresponding to the change of the fracture toughness.