制备工艺对NiAl-30Fe-Y合金组织与性能的影响

EFFECT OF DIFFERENT PROCESSES ON THE MECHANICAL PROPERTIES AND MICROSTRUCTURES OF A NiAl-30Fe-Y ALLOY

研究了铸态、挤压态、热轧态和定向凝固结晶４种不同制备工艺对ＮｉＡｌ－３０Ｆｅ－Ｙ合金组织与性能的影响。结果表明，热轧和定向凝固结晶工艺明显改善了合金性能，特别是提高了合金室温塑性。在室温下不同制备工艺其拉伸断口特征明显不同。不同制备工艺仅对微观组织形态产生影响，其合金组织皆是由先共晶Ｂ２结构β和β与（γ＋γ′）共晶相组成，定向凝固合金成长方向为＜２１１＞β‖＜１００＞（γ＋γ′）。

The effect of four different processes,as-cast,extruded,hot-rolled and directionally solidified,on the mechnaical properties and microstructures of the NiAl-30Fe-Y alloy has been investigated.The results show that the hot-rolled and directionally solidified processes improve the mechanical properties of the alloy and particularly its tensile ductility at room temperature.The tensile fracture surfaces of the alloy produced by different processes evidently exhibit different fracture characteristics at room temperature.The microstructure of the alloy produced with the four procedures all consists of pro-eutectic β phase and eutectic phase of β and (γ+γ′).Only the microstructure morphology of the alloy is under the influence of the four procedures.The growing direction of the directionally solidified alloy is <211> β‖<100> (γ+γ′)