飞秒激光加工的轴承钢表面微织构润滑减摩特性研究
发布时间：2018-07-25 13:05
【摘要】：在机械应用中,摩擦磨损会减小系统的稳定性和可靠性等重要性能,造成机械系统寿命的降低,同时摩擦也是导致能源浪费损失的重要原因,因此减少摩擦副表面摩擦磨损现象具有重要意义。通过构造表面微织构来改善摩擦副表面摩擦性能的方法,已被国内外众多学者关注,成为当前摩擦学研究热点。本文从微织构减摩理论与仿真、微织构飞秒激光加工工艺和微织构表面摩擦性能三个方面做了系统的研究。首先结合液体润滑理论和N-S方程,建立了微织构的动压润滑物理模型。根据仿真结果发现微织构的深宽比、形状、截面形状等参数对表面动压润滑具有重要影响,仿真得到了微织构区域产生流体动压与深宽比的关系曲线;对比了不同微织构形状和截面形状对动压润滑的影响,为后续的试验提供了相应的理论支持。随后对飞秒激光加工轴承钢GCr15的工艺进行了试验研究。根据试验结果,计算得到轴承钢GC15材料的飞秒激光烧蚀阈值;在此基础上分析了不同脉冲能量和脉冲个数对凹坑形貌的影响,拟合得到了凹坑深度与脉冲能量和脉冲个数的关系曲线;分析了激光重复频率、激光扫描速度及扫描次数对微沟槽加工的影响,研究表明只有合适的扫描速度和激光频率才能实现高质量的微沟槽加工;最后对阵列微织构的加工进行了探究,提出扫描方式和单点加工相结合的方式,来提高加工效率。最后采用往复摩擦试验和旋转摩擦试验两种方法,对不同微织构表面的摩擦性能进行了试验分析。试验表明,圆形微织构表面在不同速度和载荷下均具有较好的减摩性能,三角形微织构表面在不同滑动方向下摩擦系数不同;不同深宽比凹坑试验结果验证了仿真的结果;微织构表面具有最合适的面密度为0.07,此时表面摩擦系数最小;微织构表面具有更好的耐磨性能。
[Abstract]:In the mechanical application, friction and wear will reduce the stability and reliability of the system, and reduce the life of the mechanical system. At the same time, friction is also an important cause of energy waste loss. Therefore, it is of great significance to reduce the friction and wear phenomenon on the surface of friction pairs. The method of improving the friction properties of friction pairs by constructing surface microtextures has been paid attention to by many scholars at home and abroad and has become a hot topic in tribology research. In this paper, the friction reduction theory and simulation of microtextures, femtosecond laser processing and friction properties of microtextures are systematically studied. Based on the theory of liquid lubrication and N-S equation, the hydrodynamic lubrication physical model of microtexture is established. According to the simulation results, it is found that the depth to width ratio, shape and section shape of the microtexture have important influence on the hydrodynamic lubrication of the surface, and the curves of the relationship between the hydrodynamic pressure and the ratio of depth to width in the microtexture region are obtained by simulation. The effects of different microtexture shapes and cross-section shapes on hydrodynamic lubrication were compared, which provided corresponding theoretical support for further experiments. Then, the technology of femtosecond laser processing of bearing steel GCr15 was studied. Based on the experimental results, the femtosecond laser ablation threshold of bearing steel GC15 is calculated, and the effects of different pulse energy and number of pulses on the pit morphology are analyzed. The relationship between pit depth and pulse energy and pulse number is obtained, and the effects of laser repetition rate, laser scanning speed and scanning times on the machining of micro-grooves are analyzed. The research shows that only the appropriate scanning speed and laser frequency can achieve high quality micro-grooves machining. Finally, the processing of array microtexture is explored, and the combination of scanning and single-point machining is proposed to improve the processing efficiency. Finally, the friction properties of different microtextured surfaces were tested and analyzed by using reciprocating friction test and rotating friction test. The experimental results show that the circular microtextured surface has better antifriction performance under different speeds and loads, and the friction coefficient of the triangular microtexture surface is different in different sliding directions, and the results of the pit test with different depth to width ratio verify the simulation results. The optimum surface density of microtexture is 0.07, the friction coefficient of microtexture surface is the smallest, and the micro-texture surface has better wear resistance.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TG665;TH117
本文编号：2143909
[Abstract]:In the mechanical application, friction and wear will reduce the stability and reliability of the system, and reduce the life of the mechanical system. At the same time, friction is also an important cause of energy waste loss. Therefore, it is of great significance to reduce the friction and wear phenomenon on the surface of friction pairs. The method of improving the friction properties of friction pairs by constructing surface microtextures has been paid attention to by many scholars at home and abroad and has become a hot topic in tribology research. In this paper, the friction reduction theory and simulation of microtextures, femtosecond laser processing and friction properties of microtextures are systematically studied. Based on the theory of liquid lubrication and N-S equation, the hydrodynamic lubrication physical model of microtexture is established. According to the simulation results, it is found that the depth to width ratio, shape and section shape of the microtexture have important influence on the hydrodynamic lubrication of the surface, and the curves of the relationship between the hydrodynamic pressure and the ratio of depth to width in the microtexture region are obtained by simulation. The effects of different microtexture shapes and cross-section shapes on hydrodynamic lubrication were compared, which provided corresponding theoretical support for further experiments. Then, the technology of femtosecond laser processing of bearing steel GCr15 was studied. Based on the experimental results, the femtosecond laser ablation threshold of bearing steel GC15 is calculated, and the effects of different pulse energy and number of pulses on the pit morphology are analyzed. The relationship between pit depth and pulse energy and pulse number is obtained, and the effects of laser repetition rate, laser scanning speed and scanning times on the machining of micro-grooves are analyzed. The research shows that only the appropriate scanning speed and laser frequency can achieve high quality micro-grooves machining. Finally, the processing of array microtexture is explored, and the combination of scanning and single-point machining is proposed to improve the processing efficiency. Finally, the friction properties of different microtextured surfaces were tested and analyzed by using reciprocating friction test and rotating friction test. The experimental results show that the circular microtextured surface has better antifriction performance under different speeds and loads, and the friction coefficient of the triangular microtexture surface is different in different sliding directions, and the results of the pit test with different depth to width ratio verify the simulation results. The optimum surface density of microtexture is 0.07, the friction coefficient of microtexture surface is the smallest, and the micro-texture surface has better wear resistance.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TG665;TH117
【参考文献】
相关期刊论文 前6条
1 王静秋;王晓雷;;表面织构创新设计的研究回顾及展望[J];机械工程学报;2015年23期
2 李凯凯;于海武;王静秋;王晓雷;;混合织构发动机缸套的减摩试验研究[J];内燃机工程;2014年05期
3 符永宏;李成冬;华希俊;米涛;倪健;;激光毛化微凸形模具钢表面摩擦磨损性能研究[J];摩擦学学报;2009年05期
4 历建全;朱华;;表面织构及其对摩擦学性能的影响[J];润滑与密封;2009年02期
5 韩中领;汪家道;陈大融;;凹坑表面形貌在面接触润滑状态下的减阻研究[J];摩擦学学报;2009年01期
6 赵大庆;杨锋;;“top down”和“bottom up”——评我国纳米科技发展的导向问题[J];材料导报;2001年11期
相关博士学位论文 前7条
1 王钦鑫;整形飞秒激光精密微加工技术研究[D];吉林大学;2016年
2 李国强;基于飞秒激光微纳米技术的仿生功能结构研究[D];中国科学技术大学;2015年
3 孟可可;仿生超疏水金属表面的制备与性能研究[D];吉林大学;2014年
4 马晨波;织构化表面的润滑计算模型及减摩特性研究[D];中国矿业大学;2010年
5 黄永光;飞秒激光诱导金属表面微纳米结构的基础研究[D];北京工业大学;2010年
6 符永宏;提高摩擦副表面润滑减磨性能的激光微制造复合新技术研究[D];江苏大学;2008年
7 王文君;飞秒激光金属加工中的形状及形貌控制研究[D];西安交通大学;2008年
相关硕士学位论文 前1条
1 吴雪峰;飞秒激光烧蚀金属的理论与试验研究[D];哈尔滨工业大学;2006年
，本文编号：2143909
本文链接：https://www.wllwen.com/jixiegongchenglunwen/2143909.html
