GH742合金大锭型自耗锭的热变形行为和热加工工艺

Hot Deformation Behavior and Hot Working Process of Superalloy GH742 Large-scale VAR Ingot

对GH742合金自耗锭(■508 mm)的热变形行为及热加工工艺进行了研究。结果表明,在试验条件范围内,GH742合金的流变应力随变形温度的降低和应变速率的提高而迅速增大,提高变形温度能够有效地促进动态再结晶过程。GH742铸锭变形温度应在1 075℃以上,变形量控制在40%～60%。新型保温技术适用于难变形高温合金的自由锻开坯。

Hot deformation behavior and hot working process of super-alloy GH742 large-scare VAR ingot （Ф508mm） were studied. The results show that the flow stress increases drastically with the decrease of deformation temperature and the increase of strain rate. Dynamic recrystallization process can be effectively promoted by increasing deformation temperature. The proper temperature of GH742 VAR ingot is above 1075 ℃ and the optimum deformation range is 40%-60%. New heat insulation technology is suitable for the forging process of diffcult-to-deform wrought superalloy ingots.