镍基高温合金高速铣削加工表面完整性

Surface integrity on high speed milling Ni-based superalloy

采用高速铣削加工试验,研究切削速度对2种不同的镍基高温合金FGH95和Inconel718已加工表面完整性的影响规律,并观察高速铣削加工后的切屑形貌。试验结果表明：在较低切削速度范围内（800~2 000 m/min）,切削速度对表面粗糙度的影响很小,两者表面粗糙度相差不大,但在较高的切削速度范围内（〉2 000 m/min）,FGH95的表面粗糙度要大于Inconel718的表面粗糙度。在相同切削条件下,Inconel718的加工硬化率和加工硬化层深度要明显比FGH95的大,并且Inconel718表面白层的厚度大于FGH95表面白层厚度。高速铣削加工FGH95和Inconel718切屑均出现明显的锯齿化现象,并且随着切削速度的提高,锯齿化程度不断加剧以至变为碎屑。

By the experiments of high speed milling, the influence of the milling speed on machined surface integrity of two different forming process ofNi-based superalloys FGH95 and Inconel718 was investigated, and the chip morphology was observed after each experiment. The results indicate that at low cutting speed range （800-2 000 m/min）, the influence of cutting speed on surface roughness is very small, with little difference between the surface roughness of FGH95 and Inconel718, but at the high cutting speed range （〉2 000 m/min）, and the surface roughness of FGH95 is higher than the surface roughness of Inconel718. Work hardening rate and the depth of hardening layer of Inconel718 is significantly greater than FGH95 in the same cutting conditions, and the thickness of white layer of Inconel718 is greater than the thickness of white layer of FGH95 surface. Serrated chip occurs during high milling Ni-based superalloy, as the cutting speed increases, the grade of serrated tooth grows.