微小零件化学机械—机械化学协同微细磨削及微磨具关键技术

The demand for meso/micro complex parts of silicon materials with high service performance is increasingly urgent. The micro-grinding technology has large advantage in manufacturing these parts. However, due to the inherent hard and brittle characteristics of silicon materials and low performances of machine tools and grinding tools, there are several difficult problems which include large damage of machined edge, poor surface quality, severely abrasive wear and fall-off of micro-grinding tool, and low machining efficiency. For this, a micro-grinding method assisted by chemo-mechanical and mechano-chemical effects is innovatively proposed in this project. The chemo-mechanical effect is first used to modify and soften the material, which enlarges critical condition of brittle/ductile removal change and grinding efficiency. Then the mechano-chemical effect is used to remove the residual modified layer and micro-nano scale damages of edge and surface. And the machining is completed in one step with micro-grinding head bonded with combined abrasives of diamonds and oxides. The specialized chemical solutions for material modification will be studied and prepared, and the control conditions for high effective machining under the chemo-mechanical effect will be revealed. The micro-grinding heads bonded with combined abrasives will be developed and the control conditions for ultra-precision machining under the mechano-chemical effect will be revealed. Based on that, the optimized micro-grinding process assisted by chemo-mechanical and mechano-chemical effects will be built. A machining test-bed, applying the outcomes of this project, will be established to realize high efficient and ultra-precision manufacturing of meso/micro complex parts of silicon materials. The research achievements can lay theoretical foundation for the development of micro-grinding technology and improvement of manufacturing level of meso/micro parts, and thus this project has significant academic value and application prospect.

高使役性能硅基介观微小零件的潜在需求日益迫切。微细磨削技术在加工该类零件方面具有较大优势，但受制于材料硬脆特性和机床、磨具性能，存在加工边刃损伤大、表面质量差、微磨头磨粒磨损脱落严重及加工效率低等难点问题。为此，本项目创新性地提出化学机械—机械化学协同微细磨削加工方法，先引入化学机械作用改性软化材料，增大脆/延去除转变临界条件及磨削效率；再引入机械化学作用去除残留改性层及微纳尺度边刃表面损伤；并通过金刚石与氧化物复合磨料微磨头协同“一步”完成。研究制备专用化学改性液，揭示化学机械作用机制下高效率加工控制条件；研制复合磨料微磨头，揭示机械化学作用机制下超精密加工控制条件；建立化学机械—机械化学协同微细磨削优化工艺，构建应用项目成果的加工试验台，实现硅基材料微小零件的高效率超精密加工。研究成果可为微细磨削技术的发展和微小零件制造水平的提升奠定理论基础，具有重要的学术研究价值和应用前景。

高使役性能的硅基材料微小复杂结构零件的潜在需求日益迫切，微细磨削技术在加工该类零件方面具有较大优势，但还存在加工边刃损伤大、表面质量差、微磨头磨损脱落严重及加工效率低等难题。为此，本项目提出化学机械机械化学多能场复合的微细磨削加工方法与复合磨料微磨头磨具。研究了单晶硅、碳化硅、熔石英等硅基材料微细磨削损伤成因及特征，提出一种新型的边刃损伤评价模型，为评价微细磨削质量提供一种可供参考的指标；基于相变-位错理论，揭示了微细磨削中材料依次发生表层相变-相变范围增大-停滞区出现-位错成核-位错堆积-裂纹成核-裂纹随机出现的去除机理，明确了微结构边刃裂纹萌生机制；研究了化学改性液成分配比，制备出专用碱性化学改性液；建立了改性层-基体复合层磨粒作用的力学模型，揭示了改性液的改性软化及磨粒去除作用机制；建立了分层复合磨料微磨具的制备技术，研制出氧化铈与金刚石磨料分层复合磨料微磨头；构建了应用项目成果的加工试验台，建立了化学机械机械化学多能场复合的微细磨削新工艺技术，试验结果表明加工表面粗糙度可达Ra38nm，为微小复杂零件超精密高效率低成本加工提供了重要理论与技术支撑。项目成果对于提升微小零件的加工制造水平和促进高精尖装备的小型化有着重要的科学意义和实用价值。