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Fretting corrosion in automobile wheel bearings
SYSTEMATIC ABSTRACTS OF CURRENT LITERATURE the greatest effect. There is no relationship between anti-fretting properties and antiwear properties so that the latter cannot be used as criteria for predicting the fretting behaviour of greases.
415
bubblecollapse. Theliquid properties may control the jets velocity and thus affect the applied stress on surface boundaries. 6.
INSTRUMENTATION
AND TESTING
Fretting Corrosion in Automobile Wheel Bearings. D. V. Culp and J. E. Lieser, Lubrication Eng., 27
6.1. Instrumentation
(10) (1971) 350-356; 6 figs., 4 tables, 2 refs. Quantitative data from a full scale bearing test designed to simulate automobile service eonditions supplemented by lield service experience are presented to show that the optimizing of lubricants can significantly reduce the magnitude of fretting in automotive wheel bearings.
Interpretation of tbe Thickness of Lubricant Films in R&.ing Co&et. I. Examination of Measurements Obtained by X-rays. J. W. Kannel and J. C. Bell, JUIOLT,Ser. F 93
Study of the Practicabiity Ceramic T~l~~~ation Form.
of Steel Cutting with of Groove Wear
M. Tanaka and K. Takano, Nippon Tungsten Rev. 4 (1971) 74-81; 5 figs., 2 tables, 1 ref. Groove wear of carbide tools is initiated at the outside parts of the cutting section of the rake and relief face of the tool. The location of wear is the same on both faces. The length of the groove was increased with increasing side cutting edge angle. The chip contact length changed with increasing rake angle and as the chip length increased groove wear was reduced. Initial surface roughness is likely to cause groove wear. Wear of Cutting Tools. G. Barrow, Tr~~o~og~,5 (1) (1972) 22-30; 12 figs.,
18 refs. Types of tool material are discussed in relation to the properties required for effective performance in practice. Factors influencing tool wear are considered and methods of reducing tool wear reviewed. Cavitation Erosion io a Thin Film as Affected by Liquid Properties. F. F. Tao and J. K. Appeldoorn, JOLT, Ser. F 93 (4) (1971)470477; 14 figs., 8 tables, 23 refs.
The effect of liquid properties and the atmosphere environment on cavitation erosion was investigated in a thin-film cavitation apparatus. Cavitation erosion was less severe for liquids of higher gas solubility or at vapour pressures greater than 100 torr. it is possible to reduce damage by blending of liquid and environmental control, damage increases with increase of pressure. The most important factor is the differential pressure inside and outside the cavities with the dissolved gases and/or vapour serving to control this pressure differential. Evidence obtained supports the theory that erosion damage is caused by fatigue failure attributable to the impingement of liquid jets during Wenr, 21 (1972)
(4) (1971) 478-484; 6 figs., 3 tables, 17 refs. Film thickness of five lubricants between discs in rolling contact for a range of loads and speeds at 178O and 250°F have been measured by an X-ray technique. An empirical formula fitted to the data shows a much higher sensitivity of film thickness to load than is normally predicted. The X-ray measuring process has been examined for accuracy and although some weaknesses were found they do not seem to account for the anomalies of the film thickness measurement. Interpretations of the Thickness of Lubricant Fii in Roliing Contact. 2. Influence of Possible Rheological Factors. J. C. Bell and J. W. Kannel, JOLT, Ser. F, 93
(4) (1971) 485-497; 6 figs., 3 tables, 23 refs. Several theories involving realistic rheological effects have been developed in an effort to find why X-ray measured film thickness in rolling contact do not obey simple theories well, especially with respect to load effect. The analysis is based on actions in the inlet zone and the effects investigated include pressure variation of viscosity, a non-Newtonian rheology of Ree-Eyring form, and a time delay in pressure effect on viscosity. Simple theories are found for the influence of these factors on film thickness; the time delay theory is found to provide the best correlation withexperimental measurements. 6.2. Testing ofmachineparts Development of Techaiiues for the Analysis of Piion Laquers by &&a-red Spectroscopy. H. Spedding and S.F.W. Noel, Tribology, 5 (1)
(1972)31-33;5Bgs.,3refs. The procedure adopted for measuring the spectra of piston lacquers in situ is described briefly. The interpretation, particularly of the complex carbony1 region of the spectra, has been extended by work on oxygenated compounds and by selective chemical treatments of lacquers detached from piston surfaces. The results of the infra-red analysis are correlated with the chemistry of lacquer formation.
415
bubblecollapse. Theliquid properties may control the jets velocity and thus affect the applied stress on surface boundaries. 6.
INSTRUMENTATION
AND TESTING
Fretting Corrosion in Automobile Wheel Bearings. D. V. Culp and J. E. Lieser, Lubrication Eng., 27
6.1. Instrumentation
(10) (1971) 350-356; 6 figs., 4 tables, 2 refs. Quantitative data from a full scale bearing test designed to simulate automobile service eonditions supplemented by lield service experience are presented to show that the optimizing of lubricants can significantly reduce the magnitude of fretting in automotive wheel bearings.
Interpretation of tbe Thickness of Lubricant Films in R&.ing Co&et. I. Examination of Measurements Obtained by X-rays. J. W. Kannel and J. C. Bell, JUIOLT,Ser. F 93
Study of the Practicabiity Ceramic T~l~~~ation Form.
of Steel Cutting with of Groove Wear
M. Tanaka and K. Takano, Nippon Tungsten Rev. 4 (1971) 74-81; 5 figs., 2 tables, 1 ref. Groove wear of carbide tools is initiated at the outside parts of the cutting section of the rake and relief face of the tool. The location of wear is the same on both faces. The length of the groove was increased with increasing side cutting edge angle. The chip contact length changed with increasing rake angle and as the chip length increased groove wear was reduced. Initial surface roughness is likely to cause groove wear. Wear of Cutting Tools. G. Barrow, Tr~~o~og~,5 (1) (1972) 22-30; 12 figs.,
18 refs. Types of tool material are discussed in relation to the properties required for effective performance in practice. Factors influencing tool wear are considered and methods of reducing tool wear reviewed. Cavitation Erosion io a Thin Film as Affected by Liquid Properties. F. F. Tao and J. K. Appeldoorn, JOLT, Ser. F 93 (4) (1971)470477; 14 figs., 8 tables, 23 refs.
The effect of liquid properties and the atmosphere environment on cavitation erosion was investigated in a thin-film cavitation apparatus. Cavitation erosion was less severe for liquids of higher gas solubility or at vapour pressures greater than 100 torr. it is possible to reduce damage by blending of liquid and environmental control, damage increases with increase of pressure. The most important factor is the differential pressure inside and outside the cavities with the dissolved gases and/or vapour serving to control this pressure differential. Evidence obtained supports the theory that erosion damage is caused by fatigue failure attributable to the impingement of liquid jets during Wenr, 21 (1972)
(4) (1971) 478-484; 6 figs., 3 tables, 17 refs. Film thickness of five lubricants between discs in rolling contact for a range of loads and speeds at 178O and 250°F have been measured by an X-ray technique. An empirical formula fitted to the data shows a much higher sensitivity of film thickness to load than is normally predicted. The X-ray measuring process has been examined for accuracy and although some weaknesses were found they do not seem to account for the anomalies of the film thickness measurement. Interpretations of the Thickness of Lubricant Fii in Roliing Contact. 2. Influence of Possible Rheological Factors. J. C. Bell and J. W. Kannel, JOLT, Ser. F, 93
(4) (1971) 485-497; 6 figs., 3 tables, 23 refs. Several theories involving realistic rheological effects have been developed in an effort to find why X-ray measured film thickness in rolling contact do not obey simple theories well, especially with respect to load effect. The analysis is based on actions in the inlet zone and the effects investigated include pressure variation of viscosity, a non-Newtonian rheology of Ree-Eyring form, and a time delay in pressure effect on viscosity. Simple theories are found for the influence of these factors on film thickness; the time delay theory is found to provide the best correlation withexperimental measurements. 6.2. Testing ofmachineparts Development of Techaiiues for the Analysis of Piion Laquers by &&a-red Spectroscopy. H. Spedding and S.F.W. Noel, Tribology, 5 (1)
(1972)31-33;5Bgs.,3refs. The procedure adopted for measuring the spectra of piston lacquers in situ is described briefly. The interpretation, particularly of the complex carbony1 region of the spectra, has been extended by work on oxygenated compounds and by selective chemical treatments of lacquers detached from piston surfaces. The results of the infra-red analysis are correlated with the chemistry of lacquer formation.