新型铸&锻GH4096合金篦齿盘研制与考核

Development and Testing of novel Casted&Wrought GH4096 Alloy Labyrinth Disk

摘要:

采用电渣重熔连续定向凝固+3D整体锻造+等温模锻的新型铸 锻工艺制备了大尺寸GH4096合金篦齿盘锻件,研究了固溶后油冷和风冷两种冷却方式对锻件组织、性能及残余应力的影响。采用金相显微镜和扫描电镜分析了锻件的显微组织,测试了锻件的力学性能,对锻件进行了水浸分区聚焦超声波检测,开展了零件加工和试验考核。结果表明,两种固溶冷却方式的锻件经时效处理后的晶粒尺寸均为5~20μm,一次γ"相均为1~2μm。相比于固溶油冷+时效处理,固溶风冷+时效处理锻件中的二次和三次γ"相更粗、三次γ"相的含量更少、屈服强度和蠕变性能较低、内部残余应力和机加工变形量更小。GH4096合金篦齿盘锻件经超声波检测未发现超过Φ0.4mm-15dB的单显信号,杂波水平在Φ0.4mm-21dB以下。固溶风冷+时效处理的全尺寸篦齿盘零件完成了超转试验考核和破裂转速试验考核,试验结果满足设计的需求。

关键词:GH4096合金;新型铸&锻工艺;显微组织;力学性能;残余应力;超声波检测

Abstract:

The GH4096 alloy aero-engine labyrinth disk forging was produced by a novel casting wrought method which included electroslag remelting continuous directional solidification, multiple integral forging and isothermal forging and other process. Different cooling rate after solid solution treatment was analyzed on the effect of microstructure and properties of forgings. Microstructure of forgings were analyzed by optical microscope (OM) and scanning electron microscope (SEM). Mechanical properties of forgings were tested, multi-zoned ultrasonic focused inspection was uesd to detect the quality of GH4096 alloy forgings. In addition, full-size labyrinth disks were manufactured and tested. Test results show that two kinds of heat treated forgings process the comparable grain size about 5~20μm and firstly γ’ size about 1~2μm. Compare to oil cooling of solution treated forgings, the forced air cooling of solution treated forgings processes coarser secondary and thirdly γ’ phase, less thirdly γ’ phase content, lower yield strength,lower creep property, lower residual stress and machining deformation. There is no single reflected signal higher than that of Φ0.4mm-15dB, and the clutter signals are lower than Φ0.4mm-21dB. The forced air cooled solution + aging treated full-size GH4096 alloy labyrinth disk passed the over-running test and burst speed test.

Key words:GH4096 alloy; novel casting& wrought method; microstructure; mechanical property; residual stress; ultrasonic inspection