论文部分内容阅读
利用微观组织分析和化学相分析的综合方法研究了超超临界电站锅炉过热器管材用镍基高温合金Inconel 740在服役温度范围长期时效下的组织稳定性,并基于热力学模拟计算对合金的成分进行调整和改型.结果表明:合金的组织不稳定性主要表现在高温时强化相γ′相急剧长大、晶内和晶界η相以及晶界G相的形成;通过调整Al、Ti含量和降低Si含量研制了改型合金,改型合金γ′相的稳定温度得到提高,在750℃和800℃长达5 000 h时效后晶界没有出现η相和G相,表现出良好的组织稳定性.
The microstructure and chemical phase analysis were used to study the microstructure stability of the Inconel 740 nickel-based superalloy supercritical steel tube for long-term service life in the service temperature range. The composition of the alloy was calculated based on the thermodynamic simulation Adjustment and modification.The results show that the microstructure instability of the alloy is mainly characterized by the sharp growth of the γ ’phase, the η phase in the grain boundary and the G phase in the grain boundary at high temperature, Decreasing the Si content of the modified alloy was developed. The stable temperature of the γ ’phase of the modified alloy was improved. No η phase and G phase appeared at the grain boundary after aging at 750 ℃ and 800 ℃ for 5 000 h, which showed good microstructure stability Sex.