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A novel approach of three-linear-axis ultra-precision grinding with wheel path generation, tool interference checking and profile compensation is proposed and systematically investigated for fabricating aspheric surfaces. The performance of the proposed techniques is evaluated by grinding an aspheric mould insert on bindless tungsten carbide. The experimental results demonstrate that the profile error can be reduced to 0.1 μm or a lower value in peak to valley (PV) after two compensation cycles. The on-machine measurement results show agreement with the off-machine measurement results when commercially available profilometers are employed. The study confirms the feasibility of the proposed wheel path determination method and the developed profile compensation approach. A mirror surface with roughness less than 8 nm in Sa is achieved.

This study proposes a novel surface modification method known as laser-assisted rolling, which aims to refine surface grains and enhance the machinability of brittle polycrystalline materials. This method establishes a foundation for achieving a crack-free and low-damage optical surface finish. Using binderless tungsten carbide as a case study, a systematic experimental investigation was carried out with a self-developed laser-assisted rolling system. The results show that the proposed method effectively refines surface grains by introducing dense defects. It also achieves a gradient grain size crystal structure and a residual compressive stress state without causing surface cracks. The formation and evolution mechanisms of the modified layer were comprehensively studied. Moreover, this novel method is expected to offer theoretical guidance for the surface modification of other brittle polycrystalline materials.