To address surface quality defects caused by traditional mechanical polishing of gears, such as machining scratches and large surface waviness, this study proposes a novel immersed chemical-mechanical polishing (CMP) process for gear finishing. Numerical simulations were conducted in FLUENT to analyze the gear surface stress distribution and polishing fluid flow trajectories under different process conditions. The Euler–Euler method and RNG k–ε turbulence model were used to optimize process parameters and clarify the formation mechanism of ultra-smooth tooth surfaces. Experimental results for spiral bevel gears show that the proposed immersed CMP process effectively improves surface quality. The tooth profile roughness was reduced from Ra 1.531 μm to 0.509 μm, and surface scratches were significantly alleviated. These results confirm the feasibility and effectiveness of the proposed process. This study provides a reliable approach for efficient and precision polishing of complex-structured gears and extends the application of CMP technology to non-planar mechanical components.

Single-crystal diamond (SCD) has the characteristics of a hard surface and stable chemical properties, making it difficult to achieve ultra-smooth and ultra-low-damage surface polishing using conventional polishing slurries. In this study, a novel green chemical mechanical polishing (CMP) slurry containing only hydrogen peroxide, nicotinic acid, silica (SiO₂) abrasive particles and deionized water was developed to achieve ultra-smooth, ultra-low-damage (0.5 nm) and atomic-scale surface roughness (Ra 0.473 ± 0.035 nm) polishing of SCD. Additionally, the influence of diamond, silicon carbide and SiO₂ abrasive particles on the surface quality of SCD after CMP was investigated by single-factor experiments. Based on XPS characterization, the mechanism of SCD CMP was revealed: the SCD surface was first oxidized to form C-O and C=O groups, and then these groups were removed under the mechanical action of SiO₂ abrasives, ultimately achieving atomic-scale removal of the material.

Commercial computer-aided design (CAD) software is often expensive. This paper examines the use of product manufacturing information (PMI) web visualization to address the challenges faced by production site personnel and external partners collaborating on product development. These individuals need to be able to view or query PMI in model-based definition models without having to install professional CAD software. A detailed analysis of the relationships between PMI entity attributes in standard for the exchange of product model data (STEP) AP242 files was conducted. An algorithm for the automatic parsing and mapping of PMI semantics to a web browser is presented. Using linear sizes as an example, this paper introduces a prototype system with the following features: PMI web visualization; automatic linkage of PMI to associated geometry; browser-native rendering without the need for dedicated applications; and integration of graphical presentation and semantic representation. The effectiveness and feasibility of the prototype system are validated through case studies. However, the system has limitations when handling large assemblies with compound tolerances, curved dimension placements, and overlapping annotations, which presents areas for future research.