- Email: [email protected]
Sintering of columbium powder
VOL. 2 (1958/59)
SYSTEMATIC
the powder metal is sintered on a coppercoated steel plate and afterwards compressed by rolling. The methods of powder-metal rolling now in use and a new method of rolling between rolls one under another by means of a paper band are discussed. PTFE
Bearing
ABSTRrlCTS
497
As a step towards formation of design rules for ball and socket joints, a solution of the lubrication equations for an “ideal” joint under steady loading and rotation is presented. The friction for the ball is found to be higher, and the load capacity lower, than that of a plain bearing under similar conditions.
Materials.
Modern Plastics, v. 36, no. 6, Feb. 1959, p. 123 + 4 pages. Chemically inert polytetrafluorethylene compounds have low coefficients of friction, can give long service if properly designed for load and speed. Hydrodynamic Lubrication of Ball and Socket Joints. R. I. Tanner. Applied Scientific Research, Sec. A, Mechanics, Heat, Chemical Engineering, Mathematical Methods, v. 8, no. I, 1958, p.
Fixtures for Testing Pin-End Columns. A. W. Huber. ASTM Bulletin, no. 234. Dec. 1958, P. 41-45. Design and the performance of column end fixtures with cylindrical bearing surfaces. These fixtures were designed for heavy loads (maximum 2,000,ooo lb). and simulate a pin-end condition in one direction and fixedend condition in the direction at right angles to the first. The fixtures can be used for axial or eccentric column tests with equal end eccentricities.
45-51. 5. WEAR AND WEAR RESISTANCE
5. I. Materials The Impact of Space Technology on Research and Development - Structures and Materials. Richard V. Rhode and John C. Houbolt, NASA. (Presented before General Assembly, AGARD, Copenhagen, Denmark, October 20-29, 1958.) iii, 32 pp., diagrs. (Ask for NASA L-128). A broad discussion is given of the structures and materials problems that are involved in design of space-flight vehicles. Problem areas outlined and attention is focused on those areas which require increased research activity. The point of view taken is that space technology is a natural extension of aeronautical technology and that it is the environment, mission, and configuration whichset the structural problems. The nature of the spaceflight environment and the general trends in construction are therefore discussed, and this is followed by a detailed consideration of the loads, structural design, and materials problems. Some specific examples illustrating the severity of the loads and structures problems are given. Metals for Supersonic Aircraft and Missiles. D. W. Grobecker, editor. 423 pp. 1958. American Society for Metals, Cleveland. Proceedings of the conference, “Heat Tolerant Metals for Aerodynamic Applications”, held January 28 and 29, 1957 at the University of New Mexico, Albuquerque, New Mexico, under the joint sponsorship of American Society for Metals and University of New Mexico. Sintering of Columbium Powder. 0. P. Kolchin and N. P. Chuveleva.
Henry
Brutcher Translation No. 4415, 14 pp. (From Tsvetnye Metally, v. 13. no. 1z,Ig57. p. 67-70.) Henry Brutcher, Altadena, Calif. Optimum conditions of sintering for ductile, easily cold-worked columbium metal. Variation of electrical resistivity, hardness, density, weight, and percentage of foreign elements in columbium powder compacts with sintering temperature. Some Fundamental Features of Mechanochemical Attack on Metals. T. P. Hoar, University of Cambridge. (Presented at the AGARD Sixth Meeting of the Structures and Materials Panel, Paris, November 4-8, 1957.) Advisory Group for Aeronautical Research and Development. November 1957. iii, 5 pp. AGARD Rept. 158. (Ask for N-69063) The behavior of oxide films under conditions leading to their chemical failure, and under fretting, fatigue, and static stress conditions, is discussed. Probably disarrayed surface zones in a metal surface lead to the formation of less effective oxide films and also, in defilmed metal, to rapid chemical attack. The consequent effects produced under fretting corrosion, corrosion-fatigue, and stress-corrosion conditions are considered. Recent experimental work is mentioned which indicates that metal that is yielding under mechanical stress is in an especially active chemical state. The implications of this work on the mechanism of stress-corrosion cracking are considered. 5.2. Erosion and impact Erosion of Materials by Cavitation Attack. D. Peckner. Corrosion, v. 15. 1959, p. 269-274: 7 fig., 3 tables, rg ref.
SYSTEMATIC
the powder metal is sintered on a coppercoated steel plate and afterwards compressed by rolling. The methods of powder-metal rolling now in use and a new method of rolling between rolls one under another by means of a paper band are discussed. PTFE
Bearing
ABSTRrlCTS
497
As a step towards formation of design rules for ball and socket joints, a solution of the lubrication equations for an “ideal” joint under steady loading and rotation is presented. The friction for the ball is found to be higher, and the load capacity lower, than that of a plain bearing under similar conditions.
Materials.
Modern Plastics, v. 36, no. 6, Feb. 1959, p. 123 + 4 pages. Chemically inert polytetrafluorethylene compounds have low coefficients of friction, can give long service if properly designed for load and speed. Hydrodynamic Lubrication of Ball and Socket Joints. R. I. Tanner. Applied Scientific Research, Sec. A, Mechanics, Heat, Chemical Engineering, Mathematical Methods, v. 8, no. I, 1958, p.
Fixtures for Testing Pin-End Columns. A. W. Huber. ASTM Bulletin, no. 234. Dec. 1958, P. 41-45. Design and the performance of column end fixtures with cylindrical bearing surfaces. These fixtures were designed for heavy loads (maximum 2,000,ooo lb). and simulate a pin-end condition in one direction and fixedend condition in the direction at right angles to the first. The fixtures can be used for axial or eccentric column tests with equal end eccentricities.
45-51. 5. WEAR AND WEAR RESISTANCE
5. I. Materials The Impact of Space Technology on Research and Development - Structures and Materials. Richard V. Rhode and John C. Houbolt, NASA. (Presented before General Assembly, AGARD, Copenhagen, Denmark, October 20-29, 1958.) iii, 32 pp., diagrs. (Ask for NASA L-128). A broad discussion is given of the structures and materials problems that are involved in design of space-flight vehicles. Problem areas outlined and attention is focused on those areas which require increased research activity. The point of view taken is that space technology is a natural extension of aeronautical technology and that it is the environment, mission, and configuration whichset the structural problems. The nature of the spaceflight environment and the general trends in construction are therefore discussed, and this is followed by a detailed consideration of the loads, structural design, and materials problems. Some specific examples illustrating the severity of the loads and structures problems are given. Metals for Supersonic Aircraft and Missiles. D. W. Grobecker, editor. 423 pp. 1958. American Society for Metals, Cleveland. Proceedings of the conference, “Heat Tolerant Metals for Aerodynamic Applications”, held January 28 and 29, 1957 at the University of New Mexico, Albuquerque, New Mexico, under the joint sponsorship of American Society for Metals and University of New Mexico. Sintering of Columbium Powder. 0. P. Kolchin and N. P. Chuveleva.
Henry
Brutcher Translation No. 4415, 14 pp. (From Tsvetnye Metally, v. 13. no. 1z,Ig57. p. 67-70.) Henry Brutcher, Altadena, Calif. Optimum conditions of sintering for ductile, easily cold-worked columbium metal. Variation of electrical resistivity, hardness, density, weight, and percentage of foreign elements in columbium powder compacts with sintering temperature. Some Fundamental Features of Mechanochemical Attack on Metals. T. P. Hoar, University of Cambridge. (Presented at the AGARD Sixth Meeting of the Structures and Materials Panel, Paris, November 4-8, 1957.) Advisory Group for Aeronautical Research and Development. November 1957. iii, 5 pp. AGARD Rept. 158. (Ask for N-69063) The behavior of oxide films under conditions leading to their chemical failure, and under fretting, fatigue, and static stress conditions, is discussed. Probably disarrayed surface zones in a metal surface lead to the formation of less effective oxide films and also, in defilmed metal, to rapid chemical attack. The consequent effects produced under fretting corrosion, corrosion-fatigue, and stress-corrosion conditions are considered. Recent experimental work is mentioned which indicates that metal that is yielding under mechanical stress is in an especially active chemical state. The implications of this work on the mechanism of stress-corrosion cracking are considered. 5.2. Erosion and impact Erosion of Materials by Cavitation Attack. D. Peckner. Corrosion, v. 15. 1959, p. 269-274: 7 fig., 3 tables, rg ref.