摘要:

AbstractThe lubrication of sliding components in vacuum conditions offers unique challenges. High vacuum precludes the use of many conventional liquid lubricants because of vaporisation, while the lack of a naturally‐occurring oxide film on metal surfaces may cause instant seizure following the failure of a lubricant. Solid lubricants, such as molybdenum disulphide and tungsten disulphide, are also used, but are less effective than more complex liquid lubrication mechanisms. New surface treatment processes, such as diamond‐like carbon (DLC), are becoming available and may further reduce wear. The purpose of the present paper is to describe an apparatus that can evaluate solid lubricants under a wide range of contact conditions at vacua down to 3 × 10−7Torr. The wear test stage is mounted in the chamber of a Scanning Electron Microscope (SEM), which allows real‐time high magnification photography of the contact area. The complete stage may be moved in three planes to facilitate observation of the complete contact area. Realtime measurement of applied load and friction coefficient is also

ISSN:1354-4063    

DOI:10.1002/tt.3020060202

出版商:John Wiley&Sons, Ltd    

年代:1999

数据来源: WILEY

摘要:

AbstractThe use of mineral‐based lubricating oils blended with vegetable oils or their derivatives has raised the question of the detection, identification, and quantitative evaluation of these substances in formulated products. This paper addresses the problem in a systematic way, and suggests some possible solutions by means of analytical pathways using column chromatography, GLC, and HPLC techniques. The methods suggested allow the identification and evaluation of fatty acid esters with mono‐ and polyalcoh

ISSN:1354-4063    

DOI:10.1002/tt.3020060203

出版商:John Wiley&Sons, Ltd    

年代:1999

数据来源: WILEY

摘要:

AbstractOne of the aims of the Groupement Français de Coordination (GFC, branch of CEC), and their working group LM2, is to develop laboratory tests to forecast dispersivity problems for new lubricants, both gasoline and diesel. This paper looks at the development of a spot test for forecasting dispersivity, allowing correlations to be made with reference oils used in the M102E test (gasoline), and the XUD 11 ATE test (diesel). Various round robins were undertaken to establish the relative importance in terms of influence of various factors, including spot storage temperature, paper batch, and quantity of deposited oil. The work has resulted in recommendations as to method and materials

ISSN:1354-4063    

DOI:10.1002/tt.3020060204

出版商:John Wiley&Sons, Ltd    

年代:1999

数据来源: WILEY

摘要:

AbstractTwo tests for evaluating continuously variable transmission (CVT) lubricants have been developed using readily available test equipment and test parts. These tests have been designed to rank lubricants using a number of criteria relevant to the performance of the lubricant in a push‐belt variator. These include overall level of friction, friction stability, temperature dependence of friction, and load dependence of friction. Testing lubricants of different types has shown the effect of lubricant chemistry on the parameters measured and indicates that some existing fluids, a CVT fluid and passenger car motor oil, as well as an experimental fluid, should give good performance in a continuously variable transmission using a push‐belt varia

ISSN:1354-4063    

DOI:10.1002/tt.3020060205

出版商:John Wiley&Sons, Ltd    

年代:1999

数据来源: WILEY

摘要:

AbstractThe friction and wear behaviour of thin hard coatings, such as TiN and the promising class of C‐based coatings (a‐C, a‐C:H, and diamond for example), are compared under oscillating and reciprocating sliding conditions. The typical effects of test parameters, such as stroke, frequency, normal force, relative humidity and test duration, are described as a basis for the proper selection of test conditions or, conversely, for the selection of suitable coatings for particular practical applications.Friction and wear data from over 1000 vibrating tests using thin hard coatings against 100Cr6 and against Al2O3have been compiled in a database. This allows easy manipulation and comparison of test results. Using selection criteria and filter procedures (e. g., lifetime of coatings, friction limits, and critical wear rate), suitable coating systems for different test conditions can be chosen from the database. The effects of test parameters on friction and wear behaviour and changes have anyway to be known for meaningful tribotesting, as well as for the selection of coa

ISSN:1354-4063    

DOI:10.1002/tt.3020060206

出版商:John Wiley&Sons, Ltd    

年代:1999

数据来源: WILEY

摘要:

AbstractIn specially designed test equipment, consisting of a hydraulic pump loop capable of measuring oil flow rate for given output pressures, the authors have shown that increased output pressure results in an actual decrease in flow rate, this decrease being linear. It is concluded that some ‘leakage’ takes place between the gears and the pump housing, which increases when decreasing the oil velocity, for a given output pressure and temperature. Models are presented which provide a good representation of internal leakage observed in practical tests of various flu

ISSN:1354-4063    

DOI:10.1002/tt.3020060207

出版商:John Wiley&Sons, Ltd    

年代:1999

数据来源: WILEY

ISSN:1354-4063    

DOI:10.1002/tt.3020060208

出版商:John Wiley&Sons, Ltd    

年代:1999

数据来源: WILEY

ISSN:1354-4063    

DOI:10.1002/tt.3020060209

出版商:John Wiley&Sons, Ltd    

年代:1999

数据来源: WILEY

ISSN:1354-4063    

DOI:10.1002/tt.3020060201

出版商:John Wiley&Sons, Ltd    

年代:1999

数据来源: WILEY