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采用热模拟试验，研究了Ｎｂ、Ａｌ对ＧＨ１５０ 合金热塑性的影响。结果表明：增加Ｎｂ、Ａｌ含量，合金零塑性温度区间（Δｔ）增大，冷却时塑性恢复速率减慢。利用ＳＥＭ 对零塑性断口进行观察，发现断口是典型的沿晶断口，并有液化迹象。断口的表面出现许多镶嵌在晶粒表面的Ｎｂ、Ｔｉ、Ａｌ富集颗粒。Ｎｂ、Ａｌ是析出相形成元素，随着Ｎｂ、Ａｌ含量的提高，合金析出相的数量增多。在快速焊接热循环作用下，析出相周围形成低熔点成分并液化，由于焊接应力的作用，形成裂纹源而产生ＨＡＺ裂纹。因此，应适当控制ＧＨ１５０ 合金的Ｎｂ、Ａｌ含量，以保证合金有较好的焊接性能。
The effect of Nb and Al on the thermoplasticity of GH150 alloy was studied by means of thermal simulation. The results show that when the content of Nb and Al is increased, the zero-temperature range (Δt) of the alloy increases, and the plastic recovery rate slows down during cooling. Using the SEM to observe the zero-plastic fracture, it is found that the fracture is a typical intergranular fracture with signs of liquefaction. There are many Nb, Ti, Al-rich particles embedded in the surface of the fracture surface. Nb and Al are precipitated phase forming elements. With the increase of Nb and Al contents, the number of precipitated phases increases. Under the effect of rapid welding thermal cycle, low melting point components are formed around the precipitated phase and liquefied. Due to the effect of welding stress, a crack source is formed and the HAZ crack is generated. Therefore, GH150 alloy should be properly controlled Nb, Al content, in order to ensure that the alloy has better welding performance.