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On the dislocation arrangement in deformed crystals of zinc
398
Systematic Abstracts of Current Continued I.
from pp. ajo-247
DEFORMATION
of this volume.
AND FRACTURE
On the Dislocation Arrangement in Deformed Crystals of Zinc. P. Kratochvfl, Phil. Mag., 13 (122) (1966) 267; 4 figs., 12 refs. Dislocation loops which are observed in the undeformed sample are believed to originate during crystal growth. Few interactions between them and glide dislocations have been seen after deformation. Formation of triangular nodes and networks of basal dislocations seem to be typical for the sample substantially deformed. The origin of those configurations is thought to be the interaction between different basal dislocations as well as the interaction between dislocation loops growing during the deformation. Diamonds as an Engineering Matedal. J. H. Brunton, Chartered Mech. Eng., 13 (I) (1966) z-g; II figs., z tables, 44 refs. Although the number of diamonds in industry is not large, the few that are used are so vital that, without them, whole areas of technology would cease to exist. Research work in recent years has thrown new light on their properties, particularly the importance of correct orientation. With further development of synthetic production methods, it may eventually be possible to custom-build diamonds for engineering purposes. 2. ADHESION
Mutual Effect of Friction and Adhesion of Rigid Bodies. Yu. P. Toporov, Ref. Zh. Mekhan., 6 (1965) Rev. 6, A 60. g (1966)
For abstract
see Appl.
Mrch. lieu., 19 (I)
(19% 92. Interaction of Surfaces in the External Friction of Solids. B. I. Kostetskii and P. V. Nazarenko, Soviet Phys.-Doklady, IO (I) (1965) 59-60. (Translation of Doklady Akad. Nauk SSSR, r60 (I) (1965) 88-90, Jan. 1965 by American Institute of Physics, New York, N. Y.) For abstract see Appl. Mech. Rev., 19 (4) (1966)
373.
Surface Temperature with Temperaturedependent Thermal Properties. F. F. Ling and J. S. Rice, ASLE Trans., 9 (1966)
Ig5--201.
An iterative method is developed for computing quasi-stationary temperatures in a large body due to a moving heat source on the surface, considering temperature dependence of thermal properties. Thermal properties of materials are classified into six categories. For surface temperatures encountered in the moving heat source problem for which the Peclet number is large, the function (fg)-* is identified as the indicator whether it is necessary to consider temperature dependence of the relevant thermal properties. The temperature dependence of density times specific heat and thermal conductivity in dimensionless form are given by .f and g, respectively.
AND FRICTION
Investigation of the Contact Angle between Indium (1) and an Aluminium Substrate in Ultrahigh Vacuum. R. G. Aldrich and D. V. Keller, Jr., J. Appl. Phys., 36 (II) (1965) 3546-3548; I fig., r7refs. The contact angle of liquid indium resting on an aluminium plate in which both surfaces were presumably atomically clean was measured in ultrahigh vacuum as 170” & IO’, at a temperature of 158” & z°C. The deviation in angle was a function of the position around the periphery of the drop due apparently to variations in crystallographic orientation of the aluminum grains in the surface. The surface energy of the liquid indium was determined by the Bashforth and Adams technique in this system as 600 dynes/cm.
Wear,
Literature
398-409
Friction and Temperature in Rolling Sliding Contacts. J. P. O’Donoghue and A. Cameron, ASLE Trans., 9 (1966) 186-194. The importance of surface temperature in disk and gear lubrication is well established so the methods to measure it need study. It is shown that a trailing thermocouple is liable to error. The oil-film thickness in an Amsler disk machine as measured by voltage discharge is found to agree excellently with theory, providing the correct surface temperatures are used to obtain the oil viscosity. Next the effects of speed, load, viscosity, and surface finish on friction are studied. An empirical relation relating these measurements, as well as all other published data, is presented. The Effect of Time, Temperature, and Environment on the Sliding Behavior of Polytetratkoroethylene. R. P. Steijn, ASLE Trans., 9 (1966) 149-159. In sliding tests, a weighted sled on PTFE
Systematic Abstracts of Current Continued I.
from pp. ajo-247
DEFORMATION
of this volume.
AND FRACTURE
On the Dislocation Arrangement in Deformed Crystals of Zinc. P. Kratochvfl, Phil. Mag., 13 (122) (1966) 267; 4 figs., 12 refs. Dislocation loops which are observed in the undeformed sample are believed to originate during crystal growth. Few interactions between them and glide dislocations have been seen after deformation. Formation of triangular nodes and networks of basal dislocations seem to be typical for the sample substantially deformed. The origin of those configurations is thought to be the interaction between different basal dislocations as well as the interaction between dislocation loops growing during the deformation. Diamonds as an Engineering Matedal. J. H. Brunton, Chartered Mech. Eng., 13 (I) (1966) z-g; II figs., z tables, 44 refs. Although the number of diamonds in industry is not large, the few that are used are so vital that, without them, whole areas of technology would cease to exist. Research work in recent years has thrown new light on their properties, particularly the importance of correct orientation. With further development of synthetic production methods, it may eventually be possible to custom-build diamonds for engineering purposes. 2. ADHESION
Mutual Effect of Friction and Adhesion of Rigid Bodies. Yu. P. Toporov, Ref. Zh. Mekhan., 6 (1965) Rev. 6, A 60. g (1966)
For abstract
see Appl.
Mrch. lieu., 19 (I)
(19% 92. Interaction of Surfaces in the External Friction of Solids. B. I. Kostetskii and P. V. Nazarenko, Soviet Phys.-Doklady, IO (I) (1965) 59-60. (Translation of Doklady Akad. Nauk SSSR, r60 (I) (1965) 88-90, Jan. 1965 by American Institute of Physics, New York, N. Y.) For abstract see Appl. Mech. Rev., 19 (4) (1966)
373.
Surface Temperature with Temperaturedependent Thermal Properties. F. F. Ling and J. S. Rice, ASLE Trans., 9 (1966)
Ig5--201.
An iterative method is developed for computing quasi-stationary temperatures in a large body due to a moving heat source on the surface, considering temperature dependence of thermal properties. Thermal properties of materials are classified into six categories. For surface temperatures encountered in the moving heat source problem for which the Peclet number is large, the function (fg)-* is identified as the indicator whether it is necessary to consider temperature dependence of the relevant thermal properties. The temperature dependence of density times specific heat and thermal conductivity in dimensionless form are given by .f and g, respectively.
AND FRICTION
Investigation of the Contact Angle between Indium (1) and an Aluminium Substrate in Ultrahigh Vacuum. R. G. Aldrich and D. V. Keller, Jr., J. Appl. Phys., 36 (II) (1965) 3546-3548; I fig., r7refs. The contact angle of liquid indium resting on an aluminium plate in which both surfaces were presumably atomically clean was measured in ultrahigh vacuum as 170” & IO’, at a temperature of 158” & z°C. The deviation in angle was a function of the position around the periphery of the drop due apparently to variations in crystallographic orientation of the aluminum grains in the surface. The surface energy of the liquid indium was determined by the Bashforth and Adams technique in this system as 600 dynes/cm.
Wear,
Literature
398-409
Friction and Temperature in Rolling Sliding Contacts. J. P. O’Donoghue and A. Cameron, ASLE Trans., 9 (1966) 186-194. The importance of surface temperature in disk and gear lubrication is well established so the methods to measure it need study. It is shown that a trailing thermocouple is liable to error. The oil-film thickness in an Amsler disk machine as measured by voltage discharge is found to agree excellently with theory, providing the correct surface temperatures are used to obtain the oil viscosity. Next the effects of speed, load, viscosity, and surface finish on friction are studied. An empirical relation relating these measurements, as well as all other published data, is presented. The Effect of Time, Temperature, and Environment on the Sliding Behavior of Polytetratkoroethylene. R. P. Steijn, ASLE Trans., 9 (1966) 149-159. In sliding tests, a weighted sled on PTFE