表面技术
錶麵技術
표면기술
Surface Technology
2015年
9期
36-42
,共7页
L-J势%非线弹性振子%阻尼%刚度%黏滑%界面摩擦
L-J勢%非線彈性振子%阻尼%剛度%黏滑%界麵摩抆
L-J세%비선탄성진자%조니%강도%점활%계면마찰
L-J potential%non-linear elastic oscillator%damping%stiffness%stick-slip%interfacial friction
目的：研究界面摩擦过程中,原子间的相互作用关系及规律。方法基于Lennard-Jones( L-J)势理论,建立界面摩擦黏滑行为的非线弹性振子模型,并以α-Fe晶体为例进行仿真分析。结果在假设条件下,质块振动主振频率约为16 Hz；运动端宏观速度v=1×10-3 m/s是主振幅值增大的临界值；刚度系数k和阻尼系数c分别在1.0~100 N/m,1.0×10-4~1.0×10-1 N/(m/s)范围内变化时,粘滑频率和主振频率分别随二者的增大而提高；摩擦界面真实接触面积S在1.0×10-18~1.0×10-14 m2内变化时,增大摩擦界面间的法向压力将导致黏滑强度增大。仿真计算表明：摩擦界面单个原子受到的激励力与原子间作用势及晶格常数有关,质块的黏滑行为与激励力、相对滑动速度、质块质量、系统刚度系数、系统阻尼系数及真实接触面积等内外因素有关。结论相对滑动速度或真实接触面积增大时,黏滑强度增强；质块质量、系统刚度系数、系统阻尼系数增大时,黏滑强度减弱。系统刚度系数、系统阻尼系数增大时,黏滑频率增大；质块质量增大时,黏滑频率减小；相对滑动速度、真实接触面积对黏滑频率的影响不显著。
目的：研究界麵摩抆過程中,原子間的相互作用關繫及規律。方法基于Lennard-Jones( L-J)勢理論,建立界麵摩抆黏滑行為的非線彈性振子模型,併以α-Fe晶體為例進行倣真分析。結果在假設條件下,質塊振動主振頻率約為16 Hz；運動耑宏觀速度v=1×10-3 m/s是主振幅值增大的臨界值；剛度繫數k和阻尼繫數c分彆在1.0~100 N/m,1.0×10-4~1.0×10-1 N/(m/s)範圍內變化時,粘滑頻率和主振頻率分彆隨二者的增大而提高；摩抆界麵真實接觸麵積S在1.0×10-18~1.0×10-14 m2內變化時,增大摩抆界麵間的法嚮壓力將導緻黏滑彊度增大。倣真計算錶明：摩抆界麵單箇原子受到的激勵力與原子間作用勢及晶格常數有關,質塊的黏滑行為與激勵力、相對滑動速度、質塊質量、繫統剛度繫數、繫統阻尼繫數及真實接觸麵積等內外因素有關。結論相對滑動速度或真實接觸麵積增大時,黏滑彊度增彊；質塊質量、繫統剛度繫數、繫統阻尼繫數增大時,黏滑彊度減弱。繫統剛度繫數、繫統阻尼繫數增大時,黏滑頻率增大；質塊質量增大時,黏滑頻率減小；相對滑動速度、真實接觸麵積對黏滑頻率的影響不顯著。
목적：연구계면마찰과정중,원자간적상호작용관계급규률。방법기우Lennard-Jones( L-J)세이론,건립계면마찰점활행위적비선탄성진자모형,병이α-Fe정체위례진행방진분석。결과재가설조건하,질괴진동주진빈솔약위16 Hz；운동단굉관속도v=1×10-3 m/s시주진폭치증대적림계치；강도계수k화조니계수c분별재1.0~100 N/m,1.0×10-4~1.0×10-1 N/(m/s)범위내변화시,점활빈솔화주진빈솔분별수이자적증대이제고；마찰계면진실접촉면적S재1.0×10-18~1.0×10-14 m2내변화시,증대마찰계면간적법향압력장도치점활강도증대。방진계산표명：마찰계면단개원자수도적격려력여원자간작용세급정격상수유관,질괴적점활행위여격려력、상대활동속도、질괴질량、계통강도계수、계통조니계수급진실접촉면적등내외인소유관。결론상대활동속도혹진실접촉면적증대시,점활강도증강；질괴질량、계통강도계수、계통조니계수증대시,점활강도감약。계통강도계수、계통조니계수증대시,점활빈솔증대；질괴질량증대시,점활빈솔감소；상대활동속도、진실접촉면적대점활빈솔적영향불현저。
Objective To study the interaction relationship and discipline between atoms in interface friction process. Methods A non-linear elastic oscillator model of stick-slip friction during interfacial friction was established based on Lennard-Jones potential theory, then alpha Fe crystal was taken as an example and simulation experiment was conducted. Results Under the condition of hypothesis, the main vibration frequency of the mass was 16 Hz;the macro velocity equaling to v=1×10-3 m/s was the critical val-ue of the increase of main amplitude values. The stick-slip frequency and main vibration frequency increased respectively along with the augment of the stiffness and damping coefficient in the ranges of 1. 0~100 N/m and 1. 0×10-4 ~1. 0×10-1 N/(m/s), respec-tively. When the real contact area of friction interface ranged from 1. 0×10-18 to 1. 0×10-14 m2, increasing the normal pressure of friction interface caused the augment of stick-slip intension. The simulation calculation results showed that the excitation force on the upper interface atoms was related to the interatomic potential and the lattice constants, and the stick-slip behavior was related to the excitation force, relative sliding velocity, block mass, system stiffness, damping coefficient and the real contact area. Conclu-sion When the relative sliding velocity or real contact area increased, the stick-slip intensity increased. When the mass of the slid-ing block or system stiffness, damping coefficient increased, the stick-slip strength was weakened. When the system stiffness or damping coefficient increased, the stick-slip frequency increased. When the mass of the sliding block increased, the stick-slip fre-quency decreased. The effects of the relative sliding velocity and the real contact area on the stick-slip frequency were not signifi-cant.
