High- and medium-entropy alloys (HEAs) are a quite new class of materials. They have a high potential for applications from low to high temperatures due to the excellent combination of their structural properties. Concerning their application as components; processing properties, such as machinability, have hardly been investigated so far. Hence, machinability analyses with a focus on the influence of the milling process and its basic parameters (cutting speed, feed per cutting edge) on the resulting surface integrity of specimens from an equiatomic high- (CoCrFeMnNi) and a medium- (CoCrNi) entropy alloy have been carried out. A highly innovative milling process with ultrasonic assistance (USAM) was compared to conventional milling processes. Recent studies have shown that USAM has a high potential to significantly reduce the mechanical load on the tool and workpiece surface during milling. In this study, the basic machining and ultrasonic parameters were systematically varied. After machining, the surface integrity of the alloys was analyzed in terms of topography, defects, subsurface damage, and residual stresses. It was observed that USAM reduces the cutting forces and increases the surface integrity in terms of lower tensile residual stresses and defect density near the surfaces for the CoCrFeMnNi alloy. It was shown that the cutting forces and the metallurgical influence in the sub surface region are reduced by increasing the cutting speed and reducing the feed rate per cutting edge. With the CoCrNi alloy, the tool revealed severe wear. As a result, for this alloy no influence of the parameters on the machinability could be determined.

高和中熵合金 (HEAs) 是一类相当新的材料。由于其结构特性的出色组合，它们在从低温到高温的应用中具有很高的潜力。关于它们作为组件的应用；迄今为止，几乎没有研究加工性能，例如可加工性。因此，可加工性分析的重点是铣削过程及其基本参数（切削速度、每切削刃进给量）对等原子高（CoCrFeMnNi）和中等（CoCrNi）熵的试样表面完整性的影响合金已进行。一种高度创新的超声波辅助铣削工艺 (USAM) 与传统铣削工艺进行了比较。最近的研究表明，USAM 具有显着降低铣削过程中刀具和工件表面机械载荷的巨大潜力。在这项研究中，系统地改变了基本加工和超声波参数。加工后，根据形貌、缺陷、亚表面损伤和残余应力分析合金的表面完整性。据观察，USAM 降低了切削力并提高了表面完整性，因为 CoCrFeMnNi 合金表面附近的拉伸残余应力和缺陷密度较低。结果表明，通过提高切削速度和降低每个切削刃的进给速度，可以降低表面下区域的切削力和冶金影响。使用 CoCrNi 合金时，刀具磨损严重。其结果，