Abstract: Taking GH4169 alloy blade preform as the object, the deformation behavior of GH4169 alloy at high temperature was analyzed through the hot compression experiment, and the numerical simulation model of the cross wedge rolling preforming of GH4169 alloy blade was established. Meanwhile, a cross-wedge rolling experiment was carried out, and the experimental parts and simulated parts were compared to study the forming quality of the blade preform. The results show that, if the process parameters are not selected properly, the preform will be stretched and necked or even broken. The initial forming temperature will affect the surface forming quality. Rolled parts are more prone to necking when processed under high temperature conditions. At the same time, the initial forming temperature can significantly affect the forming quality in the core of the preform. At a higher initial forming temperature, larger and more microholes are easily formed in the core of the preform. The size of the microholes is mainly concentrated in the range of 20-30 μm, and the microholes are mainly nucleated where the NbC carbide falls off. Therefore, in order to obtain the GH4169 alloy blade preform without forming defect, the initial forming temperature should not be higher than 1 020 ℃, and the area reduction and the roll speed should not be higher than 55% and 10 r/min respectively.

Key words: cross wedge rolling, GH4169, stretched and necked, forming defect, microholes