摘要:

AbstractThis paper presents friction and wear data from a series of physical tests on numerous friction pairs. The tests were designed to simulate the loads, motions, and conditions typical in microscale piezoelectric actuator applications. The friction pairs tested included various combinations of steels, ceramics, and surface‐treated steels. Both high‐cycle tests and low‐endurance tests were performed and the optimum friction pairs for these applications were identified based on high friction, low wear, and low roug

ISSN:1354-4063    

DOI:10.1002/tt.3020110102

出版商:John Wiley&Sons, Ltd    

年代:2004

数据来源: WILEY

摘要:

AbstractThe tribological behaviour of a copper—steel couple similar to those in electrified railways has been studied as a function of mechanical, electrical, and environmental parameters. The experimental results obtained in an oxygen atmosphere show that this factor has a major influence on the wear behaviour. While there was a reduction in the average coefficient of friction compared to in argon, under oxygen there was twice the wear found under air, and six times that found under argon. In the absence of an electric current, the nature of the wear was essentially mild adhesive. However, with an electric current at the interface, fluctuations, particularly at high intensities, were recorded in both the coefficient of friction and the electrical contact resistance, and there was severe wear. Discussion of the results is based on examination of the wear surfaces and analysis of the phenomena observed during sliding contac

ISSN:1354-4063    

DOI:10.1002/tt.3020110103

出版商:John Wiley&Sons, Ltd    

年代:2004

数据来源: WILEY

摘要:

AbstractThe present work proposes a methodology for monitoring the wear of internal combustion engine cylinders. This could be useful in calculating the time at which maintenance should be done on such a tribosystem or in determining its lifetime. On the basis of experimental data obtained using a friction—wear simulator, and through the determination of certain standardised and non‐standardised micro‐geometric parameters of the cylinder surface that change with respect to operating time, it is shown that the characteristic that exhibits the most variation is the cylinder surface anisotropy. This factor participates to a large degree in the partial hydrodynamic lubrication mechanism of the reciprocating piston ring system and, as it is associated with the stage of wear, better expresses the characteristics of the cylinder's worn surface. As a consequence, by prescribing a limit for the maximum acceptable anisotropy as a basic criterion, the ultimate tolerable stage of wear is controlled simultaneously and vice

ISSN:1354-4063    

DOI:10.1002/tt.3020110104

出版商:John Wiley&Sons, Ltd    

年代:2004

数据来源: WILEY

摘要:

AbstractBase oil type, oil viscosity, and additive type and content have a strong influence on typical gear failures. As it is not possible to quantify the influence of a lubricant on load‐carrying capacity simply from a knowledge of the physical or chemical oil data, many test methods have been developed for the evaluation of mechanical—technological lubricant properties. Simple low‐cost bench test methods often show poor correlation with practice. From both experience and systematic investigation, it can be seen that testing of gear lubricants can be performed adequately only in gear test rigs using specified test gear geometry.The standard FZG back‐to‐back gear test rig has been developed over many years and improved for different types of gear failure simulation. The standard FZG oil test A/8.3/90 is widely used for the evaluation of the scuffing properties of industrial gear oils. Automotive gear oils of GL4 level can be tested in the step test A10/16.6R/90, and axle oils of GL5 level in the shock test S‐A10/16.6R/90. For slow‐speed regimes, the C/0.05/90:120/12 wear test can be used. The influence of lubricants on the micropitting performance of gears can be evaluated in the GF‐C/8.3/90 micropitting test. Different pitting tests are available, as single‐stage (PT‐C/9:10/90) or load spectrum (PT‐C/LLS:HLS/90) tests.The aim of this paper is to describe the influence of the lubricant on the different failure modes in gears, how to quantify this effect in adequate test methods, and how to introduce the results of such tests as determining values of the lubricant into load‐carrying

ISSN:1354-4063    

DOI:10.1002/tt.3020110105

出版商:John Wiley&Sons, Ltd    

年代:2004

数据来源: WILEY

摘要:

AbstractAttention has been focused on how to achieve intelligent automation in ferrographic diagnosis in order to overcome the subjectivity of the diagnosis process. The present paper reports on a technique of characteristic measurement developed on the basis of the VC++ 6.0 programming platform, with characteristic parameters such as area, roundness, and aspect ratio being extracted from images of wear debris based on digital image analysis. However, the extraction of characteristic parameters from a ferrographic image is not the ultimate purpose of ferrographic diagnosis. The wear particles should be classified into several pre‐decision categories and their statistical distribution should also be calculated. The grey relational grade theory is introduced in this paper as a way to recognise wear debris and a new software system has been developed to deal with the problems occurring in the automation of ferrographic diagnosis. It is shown that the identification rules can be used to treat some real wear debris images with generally satisfactory result

ISSN:1354-4063    

DOI:10.1002/tt.3020110106

出版商:John Wiley&Sons, Ltd    

年代:2004

数据来源: WILEY

ISSN:1354-4063    

DOI:10.1002/tt.3020110107

出版商:John Wiley&Sons, Ltd    

年代:2004

数据来源: WILEY

ISSN:1354-4063    

DOI:10.1002/tt.3020110108

出版商:John Wiley&Sons, Ltd    

年代:2004

数据来源: WILEY

ISSN:1354-4063    

DOI:10.1002/tt.3020110101

出版商:John Wiley&Sons, Ltd    

年代:2004

数据来源: WILEY