Belt grinding (BG), widely used in Inconel 718 machining, can result in desired surface strengthening. However, the grinding-induced strengthening effect diminishes in subsequent belt polishing (BP), thus deserving special attention. This paper proposes isotropic etching polishing (IEP) as an alternative finishing process to effectively retain the robotic BG strengthened layer and concurrently improve the surface quality of BG Inconel 718. The strengthening effect and quality of surface layers processed by BG, BG + BP and BG + IEP are systematically compared and evaluated. The results indicate that BG can introduce an ~150-μm-thickness gradient strengthened layer, featured by high microhardness, significant domain refinement, large microstrain increment, high residual compressive stress, and a strong 〈100〉 texture. The optimized IEP retains approximately 86.1% (maximum) of the strengthening effect and 75.1% of the BG strengthened layer. The microhardness of the BG + IEP surface reaches 523 HV, which is about 6 times higher than that of the BG + BP surface. The BG + IEP surface of superior quality is very smooth (platykurtic) and clean, in contrast to the rough and defective BG + BP surface. The IEP is proposed to be an effective way to simultaneously realize the BG strengthened layer retention and the surface quality improvement.

砂带磨削 (BG) 广泛用于 Inconel 718 加工，可实现所需的表面强化。然而，磨削引起的强化效应在随后的带抛光（BP）中减弱，因此值得特别注意。本文提出各向同性蚀刻抛光（IEP）作为一种替代的精加工工艺，以有效保留机器人BG强化层，同时提高BG Inconel 718的表面质量。BG、BG + BP和BG处理的表面层的强化效果和质量+ IEP 得到系统的比较和评估。结果表明，BG可以引入~150-μm厚的梯度强化层，具有高显微硬度、显着的畴细化、大的微应变增量、高的残余压应力和强的〈100〉织构。优化后的 IEP 保留了大约 86.1%（最大）的强化效果和 75.1% 的 BG 强化层。BG+IEP表面的显微硬度达到523 HV，比BG+BP表面的显微硬度高约6倍。与粗糙和有缺陷的 BG + BP 表面相比，优质的 BG + IEP 表面非常光滑（platykurtic）和清洁。IEP被认为是同时实现BG强化层保持和表面质量改善的有效途径。