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Research and development on determination of coefficients of friction between dry metallic surfaces
74
LITERATURE
AND CURRENT
of air friction and the limitation of the motion path in the case of small, free-path lengths must be taken into consideration. For the specific work requirement a simple fhmce
EVENTS
relationship with the frequency of impact and velocity is found which can be employed for presentation of the whole sphere of impact comminution.
2. ADHESION AND FRICTION The Adhesion Capacity of Dry, Small Partitle-size Materials. W. Batel. Chemie-fngenieztr-Tcchnik, v. 31, 1959, p. 343: 4 fig., 7 ref. It is shown experimentally that the adhesion and cohesion of dry, small particle-size materials often occurs as a result of adsorption layers. With the elimination of these layers the adhesion capacity disappears except when this is caused by electrostatic charges or directly by the field force of the molecules in the solid surface. The friction factor p increases with the particle size and with the elimination of the adsorption layers. Research and Development on Determination of Coefficients of Friction between Dry Metallic Surfaces. E. W. Gaylord and H. Shu. Carnegie Institute of Technology for Watertown Arsenal, U.S. Army Ordnance Corps. Oct. 1957. 49 pp. 3. LUBRICATIONAND
(Order PB 131943 from OTS, 1J. S. Department of Commerce, Washington 25, D. C., $ 1.50.)
Research was conducted to determine coefficients of static friction between dry metallic surfaces under high normal pressures, and coefficients of kinetic friction under high normal pressures and high sliding velocities. Tested were the following pairs of metals: steel rubbing on steel, titanium on steel, uranium on uranium, titanium on uranium, beryllium on uranium, and beryllium on titanium. Normal rubbing pressures ranged between 1,500 and 12,000 psi. for statically apphed loads and between I 2,000 and 21,000 p.s.i. for dynamically applied loads. Coefficients of kinetic friction were determined between various metals for rubbing speeds between 30 and 50 ft./set and rubbing pressure of 1,600 to 3,000 psi.
LUBRICANTS
3.1. Lubrication
3.2. Lubvicants
Lubrication of Titanium. N. Fatica. Clevite Research Center for Wright Air Development Center, Ii. S. Air Force, &cay 195S, 78 pp. (Order PB 131981 from OTS, U. S. Department of Commerce, Washington 25, D.C., $ 2.25.) Two testers, the Shell Four Ball and the Falex, were used in this investigation to obtain information about the frictional properties of modified titanium coatings. A comparison was made of the wear resistance of the best surface treatments with various lubricants. Correlation of wear rates with the frictional characteristics of the different systems was moderately successful in both testers. It appeared possible to obtain equivalent wear resistance in many cases using electroless nickel plates, cyanided, nitridcd, carburized, oxidized, or carburized iron-plated titanium. The higher the halogen content of the lubricant, the better were its lubricating properties. It was noted that systems showing high wear rates in one type of tester will show high wear rates in the other. The conclusion was drawn that the essential nature of the action taking place in either tester is identical. Thus any lack of correlation must be attributed to operation in widely different pressure and temperature ranges. (Part 1 of this report was released earlier and is still available from OTS. It is PB 131650, same title, Part 1, Dec. 1957, 52 PP.. $ 1.50.)
Sortenbeschrankung und Giitebewertung yen Schmierstoffen fiir Hiittenindustrie und Bergbau. Reduction of the Varieties of Types and Estimation of the Quality of Lubricants Used in the Steel and Mining Industries. Georg Heinz Gtittner. Stahl und Eisen, v. 79, no. 3, Feb. 5, 1959, p. 148-156. Measure of viscosity in lubrication engineering. Classification of lubricating oils. Pureviscous and structural-viscous lubricants. Quality control: physical and chemical methods as well as functioning tests. Investigation on lubricating oils used in rolling mills. Testing greases for roll neck bearings with high circumferential speeds of the antifriction bodies. What Determines Engine Oil Consumption? M. l’obercskin, U. N. Sunderman, and E. J. Fithian. 3tomic @‘o&Z, v. IO, Mar. 1959, p. IIO--III.
Radioactive tracers were added to diesel engine lubricating oil so that wlren the oil was burnt in the cylinders the activity would pass into the exhaust gases. By monitoring the activity in the exhaust it was possible to dcterm&e the oil consumption. A correlation between oil consumption and engine wear was made. Effect of running conditions on consumption was determined.
Wear, 3 (1960) 74
LITERATURE
AND CURRENT
of air friction and the limitation of the motion path in the case of small, free-path lengths must be taken into consideration. For the specific work requirement a simple fhmce
EVENTS
relationship with the frequency of impact and velocity is found which can be employed for presentation of the whole sphere of impact comminution.
2. ADHESION AND FRICTION The Adhesion Capacity of Dry, Small Partitle-size Materials. W. Batel. Chemie-fngenieztr-Tcchnik, v. 31, 1959, p. 343: 4 fig., 7 ref. It is shown experimentally that the adhesion and cohesion of dry, small particle-size materials often occurs as a result of adsorption layers. With the elimination of these layers the adhesion capacity disappears except when this is caused by electrostatic charges or directly by the field force of the molecules in the solid surface. The friction factor p increases with the particle size and with the elimination of the adsorption layers. Research and Development on Determination of Coefficients of Friction between Dry Metallic Surfaces. E. W. Gaylord and H. Shu. Carnegie Institute of Technology for Watertown Arsenal, U.S. Army Ordnance Corps. Oct. 1957. 49 pp. 3. LUBRICATIONAND
(Order PB 131943 from OTS, 1J. S. Department of Commerce, Washington 25, D. C., $ 1.50.)
Research was conducted to determine coefficients of static friction between dry metallic surfaces under high normal pressures, and coefficients of kinetic friction under high normal pressures and high sliding velocities. Tested were the following pairs of metals: steel rubbing on steel, titanium on steel, uranium on uranium, titanium on uranium, beryllium on uranium, and beryllium on titanium. Normal rubbing pressures ranged between 1,500 and 12,000 psi. for statically apphed loads and between I 2,000 and 21,000 p.s.i. for dynamically applied loads. Coefficients of kinetic friction were determined between various metals for rubbing speeds between 30 and 50 ft./set and rubbing pressure of 1,600 to 3,000 psi.
LUBRICANTS
3.1. Lubrication
3.2. Lubvicants
Lubrication of Titanium. N. Fatica. Clevite Research Center for Wright Air Development Center, Ii. S. Air Force, &cay 195S, 78 pp. (Order PB 131981 from OTS, U. S. Department of Commerce, Washington 25, D.C., $ 2.25.) Two testers, the Shell Four Ball and the Falex, were used in this investigation to obtain information about the frictional properties of modified titanium coatings. A comparison was made of the wear resistance of the best surface treatments with various lubricants. Correlation of wear rates with the frictional characteristics of the different systems was moderately successful in both testers. It appeared possible to obtain equivalent wear resistance in many cases using electroless nickel plates, cyanided, nitridcd, carburized, oxidized, or carburized iron-plated titanium. The higher the halogen content of the lubricant, the better were its lubricating properties. It was noted that systems showing high wear rates in one type of tester will show high wear rates in the other. The conclusion was drawn that the essential nature of the action taking place in either tester is identical. Thus any lack of correlation must be attributed to operation in widely different pressure and temperature ranges. (Part 1 of this report was released earlier and is still available from OTS. It is PB 131650, same title, Part 1, Dec. 1957, 52 PP.. $ 1.50.)
Sortenbeschrankung und Giitebewertung yen Schmierstoffen fiir Hiittenindustrie und Bergbau. Reduction of the Varieties of Types and Estimation of the Quality of Lubricants Used in the Steel and Mining Industries. Georg Heinz Gtittner. Stahl und Eisen, v. 79, no. 3, Feb. 5, 1959, p. 148-156. Measure of viscosity in lubrication engineering. Classification of lubricating oils. Pureviscous and structural-viscous lubricants. Quality control: physical and chemical methods as well as functioning tests. Investigation on lubricating oils used in rolling mills. Testing greases for roll neck bearings with high circumferential speeds of the antifriction bodies. What Determines Engine Oil Consumption? M. l’obercskin, U. N. Sunderman, and E. J. Fithian. 3tomic @‘o&Z, v. IO, Mar. 1959, p. IIO--III.
Radioactive tracers were added to diesel engine lubricating oil so that wlren the oil was burnt in the cylinders the activity would pass into the exhaust gases. By monitoring the activity in the exhaust it was possible to dcterm&e the oil consumption. A correlation between oil consumption and engine wear was made. Effect of running conditions on consumption was determined.
Wear, 3 (1960) 74