摘要
为提高C/C复合材料孔加工出口边缘表面质量,以孔出口损伤因子S_(d)值(孔出口端面损伤面积与加工后理想孔面积之比)作为孔出口质量评价指标,利用单因素及正交试验方法优化磨削工艺参数,分析孔出口边缘磨削机理并提出孔出口损伤抑制策略。结果表明,当主轴转速为12000~14000 r/min,进给速度为5~7 mm/min,超声波振幅为8~9μm时,可将S_(d)值控制在4.723×10^(-3)以内。采用孔损伤抑制策略后,S_(d)值可进一步降低61.6%。此外,C/C复合材料在超声辅助磨削加工下的S_(d)值随主轴转速和超声波振幅的增加先减小后增大,随进给速度的增加逐渐增大;在保证进给速度最优时,适当提高主轴转速及超声波振幅有助于改善孔出口表面质量,并可提高加工效率。采用在临近孔出口时降低进给速度、使用刀具侧壁对孔出口进行光磨及在工件下方加设辅助支撑的策略可进一步降低孔出口损伤。
To improve the surface quality of the exit edges of C/C composite holes,the value of the hole exit damage factor S_(d)(the ratio of the damaged area of the hole exit face to the ideal hole area after machining)is used as an indicator of hole exit quality.The grinding process parameters were optimized using single-factor and orthogonal test methods to analyse the hole exit edge grinding mechanism and propose a hole damage suppression strategy.The results show that when the spindle speed is 12000-14000 r/min,feed rate 5-7 mm/min,and ultrasonic amplitude 8-9μm,the S_(d) value could be within 4.723×10^(-3).The S_(d) value can be further reduced by 61.6% using the hole damage suppression strategy.Moreover,the S_(d) value of C/C composites under ultrasound-assisted grinding decreases and then increases with the increase of spindle speed and ultrasonic amplitude while gradually increases with increasing feed speed.When the optimum feed speed is ensured,increasing the spindle speed and ultrasonic amplitude will help to improve the surface quality of the hole exit and increase machining efficiency.The strategies of reducing the feed speed near the hole exit,using the side wall of the tool to smoothly grind the hole exit and adding an auxiliary support under the workpiece are effective in reducing hole exit damage.
作者
马超
李颂华
夏忠贤
范永中
杨闯
孙健
邓俊杰
MA Chao;LI Songhua;XIA Zhongxian;FAN Yongzhong;YANG Chuang;SUN Jian;DENG Junjie(Shenyang Jianzhu University,Shenyang 110168,China;Guizhou Aerospace Linquan Motor Co.,Ltd.,Guiyang 550008,China;National-Local Joint Engineering Laboratory of NC Machining Equipment and Technology of High-Grade Stone,Shenyang 110168,China;Hongde New Material Technology(Huludao)Co.,Ltd.,Huludao 125000,China)
出处
《航空制造技术》
CSCD
北大核心
2024年第15期109-119,共11页
Aeronautical Manufacturing Technology
基金
国家自然科学基金(51975388,52105196)
辽宁省自然科学基金(2020-BS-159)。
关键词
C/C复合材料
超声磨削
孔出口损伤
质量控制
损伤因子
正交试验
C/C composites
Ultrasonic grinding
Hole exit damage
Quality control
Damage factor
Orthogonal experiment
