重载荷往复式摩擦磨损试验机

重载荷往复式摩擦磨损试验机可以分析材料在重载荷条件下的摩擦磨损性能。基于现代测试技术设计了试验机智能测试系统,并建立了动态摩擦力数学模型进行数据处理。试验表明:该试验机可实现实时测量和存储载荷、温度、摩擦力、磨损量等,并通过表格或图像的形式显示,测量结果稳定真实,重复性好,精确度高。     

往复式摩擦磨损试验机及其计算机控制系统设计

针对不同固体材料在不同条件下的摩擦磨损实验要求,开发设计了一种往复式摩擦磨损试验机,通过测量实验中产生的摩擦力、摩擦系数和磨损量的变化来研究材料的摩擦磨损性能。为提高测试系统的精确性和实时性,将计算机辅助测试系统应用到摩擦学试验当中,通过数据采集系统和测试软件系统完成摩擦磨损数据的实时动态测试,从根本上改变了传统摩擦磨损试验机的缺点。通过对聚四氟乙烯材料的摩擦磨损性能进行实验,证明该试验机性能稳定,测试系统准确可靠。     

端面摩擦磨损自动检测系统的设计

端面摩擦磨损试验可以模拟和检测面接触摩擦副的摩擦学特性。设计了端面摩擦磨损试验自动检测系统。首先在建立摩擦力和摩擦因数测量的数学模型的基础上,设计了摩擦力参数的自动检测系统,然后设计了端面试验机的智能化测控系统。使用结果表明,使用该自动检测系统的端面摩擦磨损试验机可实时检测和处理载荷、速度、温度、摩擦力和摩擦因数等参数信息,并以表格或图像曲线形式显示,有利于对试验材料的摩擦学特性变化作出实时、客观、量化的评估。     

摩擦磨损试验机在线检测系统

现代摩擦学的试验研究对摩擦磨损试验机的测量系统提出了更高的要求。本文介绍了自行设计的强电流摩擦磨损试验机及其实时在线检测系统,主要包括试验中各参量信号的获取,A/D转换,以及对测量数据误差的软件处理方法。     

环一块摩擦磨损试验机设计研究

在滚动摩擦磨损实验技术中,摩擦系数和摩擦力是影响摩擦的重要参数,为了测量环块摩擦的特性本文设计了环块摩擦磨损试验机。本试验机中负荷模块可以实现对摩擦系数的测量试验,减小了体积;机械传动部件简单,降低了润滑剂的使用;采用闭环反馈响应系统,运动精度和测量精度都得到了提高;采用单片机编程技术对摩擦后的反馈信号进行实时采集;该试验机能够在低温环境下运行;试样夹紧装置结构简单,为实验试样的装卸提供了方便;并按照标准选则装配零件和按标准绘出了机构装配图。     

往复摩擦磨损试验机测试系统的设计

设计了一种可用于模拟和检测车辆减振器中导向套-活塞杆摩擦副动态摩擦学特性的往复摩擦磨损试验机测试系统.在分析减振器往复运动的结构和功能的基础上给出了往复摩擦磨损试验机测试系统的总体模型,建立了往复运动的数学模型.使用结果表明,该测试系统可实时检测和处理载荷、速度、温度、摩擦力以及摩擦因数等参数信息,并以表格或图像曲线形式显示,有利于对试验材料的摩擦学特性变化作出实时、客观、量化的评估.     

重负荷往复摩擦试验机结构动态特性分析

重负荷往复摩擦试验机主要用于检验往复直线运动条件下材料的摩擦磨损性能,其是否具有足够的强度、刚度和良好的动态特性,将决定试验机运行的可靠性和安全性。基于ANSYS workbench软件平台,对试验机主要结构装配体进行了模态分析和谐响应分析研究。研究表明试验机的振动主要以弯曲振动为主;通过谐响应分析研究了试验机各部分在简谐载荷作用下的振动特性,预测了试验机结构设计的薄弱环节。分析结果为试验机的使用频率范围和结构优化提供了理论依据。     

双工位往复式衬垫摩擦磨损试验机

介绍了自主研发的一种用于自润滑衬垫在不同试验条件下的双工位往复式摩擦磨损试验机,通过测量试验过程中产生的摩擦力、摩擦系数和磨损量的变化来研究衬垫的摩擦磨损性能。通过对2种不同织物型自润滑衬垫的摩擦磨损性能试验,证明该试验机性能稳定,测试系统准确可靠。     

基于单片机控制多功能摩擦磨损试验机的研制

研制了基于单片机控制的具有摩擦副等效电阻检测功能的摩擦磨损试验机.不仅可以获得动态的摩擦系数信息,同时获得摩擦副之间等效动态电阻的变化,进而全方位掌握摩擦磨损过程.利用上位个人计算机人机界面和下位单片机单元组成了该设备核心控制系统.研制的设备工作稳定,性能可靠.     

义齿材料摩擦磨损试验机及控制系统设计

根据义齿摩擦磨损试验环境标准开发设计了温度和湿度可控制的往复式摩擦磨损试验机.该试验机采用曲柄导杆滑块机构实现往复运动,使用球一盘接触方式进行试件摩擦磨损,利用半导体应变片对摩擦过程中摩擦系数进行动态跟踪测试,通过调整砝码实现正压力的改变,通过改变偏心轮的偏心距实现往复行程变化.该试验机不但可对义齿材料进行摩擦磨损试验,还可对金属及其他非金属材料进行摩擦磨损试验.     

利用液压控制往复实验机实现静摩擦测量

析了静摩擦系数的影响因素和测量方法特点,介绍了一种利用液压控制的曲柄滑块机构驱动往复式摩擦磨损实验机测量静摩擦系数的方法,并进行了实际测试检验。     

半金属基粉末摩擦片摩擦磨损性能研究

在不同工况下研究半金属基粉末摩擦片与淬火45#钢配副时,载荷和转速对其摩擦磨损性能的影响,并分析其磨损机制。结果表明,在油润滑和水润滑下,半金属基摩擦片高速下的磨损量要明显低于低速下的磨损量,而干摩擦下其高载高速下的磨损要高于高载低速时的磨损量。油润滑下随载荷的增大,半金属基摩擦片的摩擦因数逐渐升高;水润滑下随载荷的增大,高速时摩擦因数先增大后减小,低速时则逐渐降低;干摩擦下随载荷的增大,高速时摩擦因数呈现出先升高后降低再升高的趋势,低速时则先升高后降低。干摩擦时摩擦面十分粗糙,有比较明显的沟状磨痕和硬质颗粒脱落后残留的凹坑;而水润滑和油润滑时摩擦面较为光滑。     

试验参数对人工滑液边界润滑条件下超高分子量聚乙烯/Ti6Al4V往复摩擦磨损行为的影响

采用自行研制的往复摩擦磨损试验机,在法向载荷50 N、往复频率1 Hz、摩擦副接触形式为圆环外圆周/平面、初始线接触长度为6 mm、相对湿度为80%的试验条件下,研究了钛合金表面粗糙度、试验环境温度、试验延续时间、滑液成分等试验参数对UHMWPE/Ti6A14V摩擦副的往复摩擦磨损行为的影响.结果表明,这些试验参数均显著影响UHMWPE/Ti6A14V摩擦副的往复摩擦磨损行为;在环境温度20℃、25%小牛血清去离子水溶液边界润滑、180 min往复摩擦磨损试验条件下,当钛合金表面粗糙度由Ra0.04 μm增加至Ra0.06μm时,摩擦副的平均摩擦因数由0.033增加至0.096,UHMWPE试样磨损量由0.131 mm3,增加至0.149 mm3;在钛合金表面粗糙度为Ra0.06μm、25%小牛血清去离子水溶液边界润滑、180 min往复摩擦磨损试验条件下,当试验环境温度由10℃上升至37℃时,摩擦副的平均摩擦因数由0.135减少至0.077,UHMWPE试样磨损量由0.188 mm3减少至0.134 mm3.     

Study on dynamic friction characteristics in reciprocating friction drive system

The dynamic friction characteristics of a reciprocating friction drive system are investigated under conditions of dry contact using 0·45% carbon steel pair. Three friction modes are found during the operation, i.e. stick-slip, sticking and a transition region. The critical operating conditions in classifying these three modes are examined under various driver speeds, normal loads and spring constants. The critical values of driver speed and normal load increase with increasing spring constant. Generally, in the friction drive system the disappearance of the stick-slip results in smooth rolling. It is also found that the slope at the first period of slip on the traction force–relative slip velocity curve would have a transition from negative to positive value when the friction mode of stick-slip changes into sticking. Moreover, results show that the sticking mode gives the best positioning accuracy with the least wear on the contact surfaces. In addition, a transition from severe wear to mild wear is found when the friction mode is transferred from stick-slip to sticking only.     

A procedure for evaluating the positioning accuracy of reciprocating friction drive systems

The dynamic characteristics of stick-slip motion in reciprocating friction drive systems are investigated under dry contact using a 0.45% carbon steel pair. Based on this dynamic analysis, the stick-slip motion can be eliminated under certain experimental conditions depending upon driver speed, normal load and spring constant. The effects of normal load, driver speed, and spring constant on the positioning accuracy of the reciprocating friction drive system are examined under harmonic oscillation without stick-slip motion. Results show that at very low spring constants, the slip increases with increasing driver speed such that higher normal load has better positioning accuracy or smaller slip than does lower normal load. However, at high spring constants and high normal loads, there exhibits severe wear or peak at two limit positions on the sliding region. As a result, smaller normal loads have a better positioning accuracy than larger normal loads due to severe wear at high normal loads.     

智能往复密封件摩擦力检测装置的研制

Aiming at the problem of automatic detection of the friction of hydraulic reciprocating seals under the condition of high pressure and multi-cycle times,based on the detection principle of the starting friction and the dynamic friction of the reciprocating seals,a detecting system was designed,and the hardware configuration,PLC software design and man-machine interface design of the control system of the detecting device were done,the friction detecting device of reciprocating seals was eventually obtained based on PLC and kingview. The friction test of O-ring seals under the pressure of 25 MPa and recurring 1 000 times was done by the detecting device. The results indicate that the detecting device can detect the dynamic and starting friction of reciprocating seals under the complex condition of high pressure and achieve the test operation process and detection process in the man-machine interface,realize the detection accuracy of 0.65 N,the detection process is stable and reliable a high degree of automation and human-computer interaction. [ABSTRACT FROM AUTHOR]     

Sliding friction and wear of magnesium alloy AZ91D produced by two different methods

Alloy AZ91D is a leading magnesium alloy used for structural applications. It contains aluminum and zinc as principal alloying elements. This alloy is normally die-cast, but recent developments in semi-solid injection molding (Thixomolding^®), which offers certain processing advantages, produces a slightly different microstructure than die-casting, and it was of interest to determine whether the two processing routes would measurably affect the friction and wear of AZ91D. The present work involved ambient air, room temperature testing of die-cast (DC) and Thixomolded^® (ThM) AZ91D, in both unidirectional and reciprocating sliding motion, using stainless steel type 440C as the counterface. After running-in, the average sliding friction coefficients in both types of test fell into the range of 0.29–0.35, irrespective of processing method. The formation of a built-up edge raised the friction slightly in unidirectional tests compared with reciprocating tests. The average wear rate of the ThM alloys in reciprocating sliding was approximately 25% lower than that for DC alloys. However, the wear rates of the magnesium specimens in unidirectional sliding were comparable for DC and ThM materials. Owing to the transfer of magnesium, there was no measurable wear on the stainless steel 440C balls. The wear mechanism during sliding involves the formation of thin, narrow shards along the edges of wear grooves which break off to produce loose particles.     

Tribological behavior of reciprocating friction drive system under lubricated contact

The dynamic friction and wear behaviors are investigated in reciprocating friction drive system using a 0.45% carbon steel pair. The effects of various operating parameters on the traction force, stick and slip time, and friction modes are examined under the lubricated contacts. Moreover, the critical operating conditions in classifying three friction modes are also established. Results show that the fluid friction induced by the shearing of lubricant dominates the variation of traction force and produces the positive slope γ at the first period of slip in the traction force–relative sliding velocity curve. The γ value decreases at higher driver speed during stick-slip motion due to the thicker fluid film and shear thinning effect. The γ value increases due to the asperity interactions as the friction region is transferred from stick-slip to sticking with normal load from 196 to 980 N. Furthermore, it is also found that the static friction force is independent of stick time for the tangential loading rate ranged from 1.12 to 16.8 s⁻¹. The transition region produces the severest wear under the different driver speeds, but the wear is insensitive to the friction regions and the severe wear only occurs at higher normal load due to the action of Hertzian contact.     

石墨烯/MoS2复合涂层多环境下的摩擦学性能

以MoS2作为润滑剂,以石墨烯(GE)作为润滑添加剂,采用喷涂法在GCr15钢样片表面制备不同含量的GE/MoS2复合涂层.利用HSR-2M型高速往复式摩擦磨损试验机测试涂层在干摩擦及海水环境中的摩擦磨损性能,并分析了磨痕形貌及磨损机制.结果表明:添加适量石墨烯可明显改善MoS2涂层的摩擦磨损性能,且海水环境中涂层的摩...