GH4169铸锭中夹杂物的类型及分布规律

高温合金中夹杂物是影响合金冶金质量和使用性能的主要因素。采用三联冶炼工艺对GH4169合金进行冶炼，并利用配有能谱仪的扫描电镜系统研究了VAR铸锭边缘及顶端区域夹杂物类型与分布的变化情况，为夹杂物的进一步控制提供参考。结果表明，在横向方向上，随试样所在位置远离铸锭边缘，夹杂物的平均尺寸由3.15 μm递减至2.58 μm，其数量密度由2 291 N/mm²（N代表夹杂物个数）降低至1 429 N/mm²；在纵向方向上，随试样所在位置远离铸锭顶端，夹杂物的平均尺寸由3.47 μm递减至2.84 μm，其数量密度由1 453 N/mm²降低至904 N/mm²，而合金中均包含5种类型的夹杂物，其类型与试样所在位置无关。最终，本实验初步判定φ508 mm的GH4169铸锭较为合适的车削量与切头量分别为30~40 mm和110~120 mm。

Type and distribution of inclusion in GH4169 nickel based superalloy

Inclusion is the main factor affecting the metallurgical quality and mechanical property of the Ni-based superalloys. In the present research, triple-melting techniques were used to refine the microstructure of GH4169 superalloy. Scanning Electron Microscopy (SEM) with an EDS were used to analyze the types and the distribution of inclusions in the edge and top region of the VAR ingot. The results showed that the average size and the amount of inclusions decreased from 3.15 μm to 2.58 μm and 2 291 N/mm² to 1 429 N/mm², as the sample was located away from the edge of the ingot. And the average size and the amount of inclusions decreased from 3.47 μm to 2.84 μm and 1 453 N/mm² to 904 N/mm², as the sampling locations moved away from the top of the ingot. Among the five main types of inclusions in the ingot, the rest of the types were independent of the sampling location. Finally, in this research, the amount of turning and cutting were tentatively determined to be 30-40 mm and 110-120 mm for the φ508 mm GH4169 VAR ingot.