| 摘要: |
| 为改善高强钢内螺纹的表面质量，提升螺纹的疲劳寿命和可靠性能，将超声滚压强化技术应用于高强钢大直径内螺纹。采用光学显微镜、显微硬度仪、应力测试仪和疲劳试验机等仪器对滚压前后的螺纹试件表面的显微形貌、粗糙度、硬度、残余应力和疲劳寿命等进行分析。结果表明：超声滚压后螺纹表面残留的加工痕迹可基本消除，牙底表面粗糙度较未滚压降低约50%，较普通滚压降低约30%；超声滚压后表面硬度较未滚压提升17%，而较普通滚压提升约14%；超声滚压后表面残余压应力较未滚压提升60%，而较普通滚压提升约50%。超声滚压后工件疲劳寿命可达到未强化工件疲劳寿命的5倍以上。综上所述，超声滚压强化对于高强钢大直径内螺纹表面质量具有良好的提升效果。 |
| 关键词: 超声 滚压 内螺纹 表面质量 疲劳 |
| DOI：10.3969/j.issn.1007-9289.2014.02.011 |
| 分类号: |
| 基金项目: |
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| High-strength Steel Large-diameter Internal Thread Strengthening by Ultrasonic Burnishing Technology |
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LI Ruifeng, ZHANG Deyuan, CHENG Minglong
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School of Mechanical Engineering and Automation, Beijing University of Aeronautics and Astronautics, Beijing 100191
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| Abstract: |
| In order to improve the surface quality of highstrength steel internal thread, enhance the fatigue life and reliability of the thread, the ultrasonic burnishing technology is used to strengthen highstrength steel largediameter internal thread. The microscopic surface topography, roughness, hardness, residual stress and fatigue life of the thread are detected and compared before and after ultrasonic burnishing by using optical microscope, surface topography measurement instrument, micro hardness tester, stress tester and fatigue machine. The results show that the residual defects on the thread surface can basically be eliminated after ultrasonic burnishing. The surface roughness using ultrasonic burnishing is reduced by 50%, traditional burnishing reduces by 30%. Ultrasonic burnishing enhanced surface hardness by 17%, traditional burnishing improved by 14%. Ultrasonic burnishing enhanced residual stress by 60%, traditional burnishing improved by 50%.The fatigue life of the large diameter internal thread after ultrasonic burnishing improves about 5 times than that of before. In summary, the ultrasonic burnishing technology has a good effect to improve surface quality of highstrength steel largediameter internal thread. |
| Key words: ultrasonic burnishing internal threads surface quality fatigue life |
