GH4720Li合金细晶棒材制备的热加工工艺研究

Hot Working Technology of Manufacture of GH4720Li Superalloy Fine Grain Bar

通过合理的热加工工艺获得组织均匀细小的棒材是难变形高温合金GH4720Li研制成功的关键和难点。通过对变形高温合金开坯工艺调研以及在GH4720Li合金MTS热模拟实验和数值模拟基础上,对开坯工艺参数进行了初步确定,据此采用2000t快锻机对406mm的GH4720Li合金铸锭进行了开坯试制,获得的棒材组织均匀、细小,性能优良。实验结果表明,得到的GH4720Li合金开坯工艺参数合理可行。

It is crucial to get uniform and fine grain microstructure for difficult-to-deform GH4720Li superalloy by appropriate hot deforming technology. The law of superalloy cogging and simulation with finite elements and MTS method for GH4720Li superalloy are investigated and the cogging pa- rameters are preliminarily confirmed. On the basis of experimental results, a 406mm diameter ingot was trial-cogged by 2000t quick-forging press. The obtained grain microstructure is uniform and fine. It proves that the cogging parameters obtained by experiments are proper.