SiCf/SiC复合材料激光烧蚀辅助铣削材料去除机理与加工表面质量评价
Material Removal Mechanism and Evaluation of Machined Surface Quality of SiCf/SiC Composites by Laser Ablation-assisted Milling
李晗 1章程 1陈杰 2安庆龙 1陈明1
作者信息
- 1. 上海交通大学机械与动力工程学院 上海 200240
- 2. 航空工业成都飞机工业(集团)有限责任公司 成都 610091
- 折叠
摘要
现代航空部件对材料的耐高温性、高强度和轻量化提出了更高要求.SiCf/SiC复合材料具有优异的综合性能,但其高脆性和各向异性使其高性能制造面临挑战.通过激光烧蚀预实验,掌握了 SiCf/SiC复合材料激光烧蚀产物的物相组成和烧蚀机理,探究了激光参数对烧蚀性质的影响规律.通过常规铣削和激光烧蚀辅助铣削的对比实验,分析了常规铣削、部分烧蚀-铣削和完全烧蚀-铣削三种不同加工策略的材料去除机理,探究了烧蚀层占比对加工表面质量的影响规律.研究表明:激光烧蚀产物主要由3C-SiC和非晶态SiO2组成.常规铣削加工中,纤维发生宏观脆性断裂,己加工表面存在多处裂纹、凹坑等加工缺陷.部分烧蚀-铣削中,纤维断裂以微观脆性断裂为主,少部分位置发生了纤维拔出和宏观脆性断裂.完全烧蚀-铣削加工中,纤维发生了微观脆性断裂,基体发生鳞状破碎.激光烧蚀辅助铣削加工质量优于常规铣削,部分烧蚀-铣削和完全烧蚀-铣削的表面粗糙度基本相同.低烧蚀层占比和高烧蚀层占比下进行铣削加工切削力差距较小.低烧蚀层占比的铣削加工中,纤维以微观-宏观脆性断裂为主;高烧蚀层占比的铣削加工中,大部分纤维发生了微观脆性断裂.综上所述,部分烧蚀-铣削和低烧蚀层占比是较优的加工方案.
Abstract
The high temperature resistance,high strength and light weight of SiCf/SiC composites are required for modern aerospace components,and SiCf/SiC composites have excellent comprehensive performance,but their high brittleness and anisotropy make it a challenge for high-performance manufacturing.Through the laser ablation pre-test,the physical phase composition and ablation mechanism of laser ablation products of SiCf/SiC composites are grasped,and the influence of laser parameters on the ablation properties is investigated.Through the comparison experiments of conventional milling and laser ablation-assisted milling,the material removal mechanisms of three different processing strategies,namely,conventional milling,partial ablation-milling and complete ablation-milling,are analysed,and the influence of the ablation layer ratio on the processing surface quality is investigated.It is shown that the laser ablation products are mainly composed of 3C-SiC and amorphous SiO2.In conventional milling,macroscopic brittle fracture of fibres occurred,and machining defects such as multiple cracks and pits existed on the machined surface.In partial ablation-milling,fibre fracture is dominated by microscopic brittle fracture,and fibre pull-out and macroscopic brittle fracture occurred at a few locations.In the full ablation-milling process,microscopic brittle fracture of fibres occurred,and scale fracture of the matrix occurred.The quality of laser ablation-assisted milling machining is superior to conventional milling,and the surface roughness was essentially the same for partial ablation-milling and complete ablation-milling.The difference in cutting force between milling with low and high ablative layer percentage is small.Micro-macro brittle fracture dominated the fibres in the milling process with low ablative layer percentage;micro-brittle fracture occurred in most of the fibres in the milling process with high ablative layer percentage.In summary,partial ablation-milling and low ablative layer ratio are the preferred processing solutions.
关键词
SiCf/SiC复合材料/激光辅助铣削/材料去除机理/加工质量Key words
SiCf/SiC composite/laser-assisted milling/material removal mechanism/machining quality引用本文复制引用
基金项目
航空发动机及燃气轮机基础科学中心资助项目(P2022-A-IV-002-001)
出版年
2024
NETL
NSTL
万方数据