| Ausrolling Sintered Steels for Bearing Elements |
92 |
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| Authors:
Sean T. Kuplen; Maurice F. Amateau; Nagesh Sonti; Richard A. Queeney; PENNSYLVANIA STATE UNIV STATE COLLEGE
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 | The mechanical behavior of ausrolled sintered AISI 4600 steel, with carbon contents of 0.8 and 1.0 wt%, has been investigated. Two types of ausroll processes were used to induce plastic deformation. The ausroll processing can lead to significant changes in hardness and density. Rolling contact fatigue endurance is markedly enhanced. |
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| Intermetallic Matrix Composites--A Status Report |
92 |
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| Authors:
Maurice F. Amateau; Ram B. Bhagat; PENNSYLVANIA STATE UNIV STATE COLLEGE
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| This is a status report on the recent advances in the development of intermetallics (aluminide, silicide, etc.) reinforced with particles, whiskers, discontinuous fibers, or continuous fibers. processing methods such as powder metallurgy techniques, diffusion bonding, plasma spraying, pressure casting and xd used for fabricating intermetallic matrix composites (imcs) are described. also included is a brief discussion on process modeling. major issues in developing the technology for imcs include the coefficient ... |
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| Mechanical Response of Surface-Ausrolled Sintered Steel |
91 |
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| Authors:
Richard A. Queeney; Sean T. Kuplen; Maurice F. Amateau; Nagesh Sonti; PENNSYLVANIA STATE UNIV UNIVERSITY PARK
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| A study has been conducted on the finishing potential, via ausforming, of pressed and sintered steel surfaces; steels corresponding to a 4600 composition, with carbon additions sufficient to produce 0.8 wt% and 1.0 wt% in the finished product, were austenitized and quenched to 230 C; their surfaces were subsequently ausrolled at 230 C and quenched to room temperature; surface and near surface densification rates were determined; mechanical responses of the ... |
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| Laminate Processing and Properties of Oriented SiC Whisker-Reinforced Composites |
91 |
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| Authors:
Mianxue Wu; Gary L. Messing; Maurice F. Amateau; PENNSYLVANIA STATE UNIV UNIVERSITY PARK CENTER FOR ADVANCED MATERIALS*
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| Fabrication of composite materials by laminate processing provides excellent control of both whisker orientation and whisker placement. Whiskers were oriented by tape casting and composites fabricated by lamination. Due to their orientation and thus higher percolation threshold, dense composites with up to 50 vol% whiskers could be fabricated. Samples with whiskers oriented perpendicular to the crack propagation direction (L-type) were always stronger and tougher than samples with whiskers oriented parallel ... |
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| High Pressure Squeeze Casting of Unidirectional Graphite Fiber Reinforced Aluminum Matrix Composites |
89 |
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| Authors:
Robert J. Sample; Ram B. Bhagat; Maurice F. Amateau; PENNSYLVANIA STATE UNIV STATE COLLEGE
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| High pressure squeeze casting has been developed to fabricate unidirectional fiber reinforced metal matrix composites having a wide range of fiber volume fraction. the process development required innovative die-design in order to minimize the direct contact of molten metal with the metallic die, to prevent liquid metal escape from the die, to ensure fast infiltration and rapid solidification under high pressure. however, the application of high pressure causes certain difficulties, ... |
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| Damping Behavior of Planar Random Carbon Fiber Reinforced 6061 Al Matrix Composites Fabricated by High-Pressure Infiltration Casting |
89 |
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| Authors:
Ram B. Bhagat; Maurice F. Amateau; Edward C. Smith; PENNSYLVANIA STATE UNIV UNIVERSITY PARK APPLIED RESEARCH LAB
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| This paper describes the damping behavior of carbon fiber reinforced aluminum matrix composites. the composites were fabricated by a high-pressure infiltration casting technique using planar random carbon fiber mats as the reinforcement and 6061 al as the matrix. the damping measurements were carried out on cantilever beam specimens vibrated at resonant frequencies in the first three modes of flexure vibration. the damping capacity of the matrix aluminum and the composites ... |
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| MECHANICAL BEHAVIOR OF METAL-MATRIX COMPOSITES |
FEB 82 |
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| Authors:
John E. Hack; Maurice F. Amateau
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| the papers presented in this volume provide an overview of recent experimental and theoretical research related to the structure, mechanical properties, and fracture behavior of metal-matrix composites. topics discussed include: thermal degradation and the tensile properties of unidirectionally reinforced fp-a1203/ez33 magnesium composites; the interface structure of heat- treated aluminum-graphite fiber composites; and micromechanisms of crack growth in a fiber-reinforced, titanium-matrix composite. the discussion also covers the effects of hot rolling ... |
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| Transverse Fracture Behavior of Graphite-Aluminum Composites. |
15 MAR 1978 |
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| Authors:
Maurice F. Amateau; Dennis L. Dull; AEROSPACE CORP EL SEGUNDO CALIF MATERIALS SCIENCES LAB
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| A determination was made of the transverse tensile strength of graphite-aluminum composites produced from various fiber and matrix compositions and by a variety of processing methods. Processing methods included the standard Ti-B chemical vapor deposition process and modifications to that process, the sodium process, and the nickel-coated fiber method. Precursor rayon, pitch, high-modulus polyacrylonitrile (PAN) and low-modulus PAN fibers were investigated, as well as 201, 6061, and 1100 aluminum-alloy matrices. ... |
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| The Corrosion of 6061 Aluminum Alloy-Thornel 50 Graphite Composite in Distilled Water and NaCl Solution. |
06 MAY 1975 |
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| Authors:
Dennis L. Dull; William C. Harrigan Jr.; Maurice F. Amateau; AEROSPACE CORP EL SEGUNDO CALIF LAB OPERATIONS
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| The corrosion behavior of a 6061 aluminum alloy-Thornel 50 graphite composite has been examined in both distilled water and 3.5% NaCl solution at three temperatures: 298K (25C), 323K (50C), and 348K (75C). The corrosion rate was determined by the weight change and was monitored for times up to 1000 hr. The corrosion rates were maximum immediately after the initial immersion and decreased with increasing time of exposure. The NaCl solution ... |
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| Mechanical Properties of Aluminum Alloy-Graphite Fiber Composites. |
21 FEB 1975 |
32 pages |
| Authors:
Maurice F. Amateau; William C. Harrigan Jr.; E. George Kendall; AEROSPACE CORP EL SEGUNDO CALIF MATERIALS SCIENCES LAB
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 | The report discusses progress made on optimizing the mechanical properties of aluminum-graphite composites consolidated by liquid-phase hot pressing. Various matrix alloys, fabrication parameters, fiber fractions, and lay-up geometries are considered. The properties investigated include: tensile, compressive, and flexture strength; modulus; and fatigue. |
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| Fatigue Crack Growth in Ti-6Al-4V from Threshold to Unstable Fracture, |
30 NOV 1973 |
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| Authors:
Maurice F. Amateau; William D. Hanna; E. George Kendall; AEROSPACE CORP EL SEGUNDO CALIF LAB OPERATIONS
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| The fatigue crack growth of Ti-6Al-4V in the diffusion bond annealed condition was examined in the range of growth rates from 10 to the minus 12th power to 10 to the minus 4th power m/cycle with the use of compact tension and part-through-crack specimens. The effects of cyclic frequency and maximum stress were investigated. Fractured surfaces were examined by scanning electron microscopy over the entire range of crack growth. The ... |
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| Comparison of First Quadrant Yield Loci for Ti-6Al-4V with Those Predicted by Knoop Hardness and Strain Ratio Measurements. |
15 OCT 1973 |
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| Authors:
Maurice F. Amateau; William D. Hanna; AEROSPACE CORP EL SEGUNDO CALIF LAB OPERATIONS
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| The first quadrant yield loci of the Ti-6Al-4V alloy determined by means of tensile tests in the rolling and transverse directions and compression tests in the thickness direction were compared with those predicted by Hill's theory of anisotropic yielding and Knoop hardness measurements. Sheet material in the hot-rolled, cold-rolled, and mill-annealed conditions possessing various degrees of anisotropy were examined. The loci predicted from the Knoop hardness measurements did not agree ... |
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| Texture Strengthening of Spin-Forged Ti-6Al-4V Alloy. |
15 JAN 1972 |
26 pages |
| Authors:
Maurice F. Amateau; AEROSPACE CORP EL SEGUNDO CALIF LAB OPERATIONS
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| Ti-6Al-4V plates were spin-forged into hemispheres so that the effect of the spinning process on plastic strain anisotropy could be examined. Spinning temperatures were varied from 400 to 1725F, and plastic strains in the longitudinal and transverse directions were measured. The plastic strain anistropy and texture developed by spin-forging were similar to those produced by other forms of processing and resulted in texture strengthening at low spinning temperatures. (Author) |
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| The Effect of Microstructure on Fatigue Crack Propagation in Ti-6Al-6V-2Sn Alloy. |
20 OCT 1971 |
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| Authors:
Maurice F. Amateau; W. Dave Hanna; E. George Kendall; AEROSPACE CORP EL SEGUNDO CALIF LAB OPERATIONS
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| The fatigue crack growth behavior of Ti-6Al-6V-2Sn was investigated for five different microstructures, using contoured double-cantilever beam specimens. The fatigue crack growth behavior was compared with the mechanical strength, toughness, and ductility properties for each microstructure. The fatigue fracture suffaces were examined with a scanning electron microscope. Annealed structures consisting of equiaxed primary alpha have the lowest crack growth resistance, while the acicular alpha microstructure resulting from beta annealing has ... |
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| Fatigue Crack Growth Behavior of a High-Strength Steel. |
15 SEP 1971 |
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| Authors:
Maurice F. Amateau; Ernest G. Kendall; AEROSPACE CORP EL SEGUNDO CALIF LAB OPERATIONS
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| Fatigue crack growth behavior of high-strength Ladish D6AC steel was examined under various conditions of frequency, environment, temperature, stress ratio, and stress intensity history. Materials with fracture toughness ranging from 50 to 100 ksi/sq. in., but with the same yield strength of 220 ksi, were examined. Variations in fracture thoughness do not have a strong effect on crack growth rate at stress intensity levels within the log-linear portion of the ... |
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| The Effect of Processing on Plastic Strain Anisotropy of Ti-6Al-4V, |
25 SEP 1970 |
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| Authors:
Maurice F. Amateau; Dennis L. Dull; Louis Raymond; AEROSPACE CORP EL SEGUNDO CALIF LAB OPERATIONS
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| The plastic strain anisotropy of Ti-6Al-4V was examined after various thermo-mechanical treatments, including heat treating, rolling, and forging. The processing temperatures were varied from room temperature to 1950F. The anisotropy, in terms of the strain ratio R, was measured by post-yield strain gages in the three principal directions. The results were correlated with the (0002) pole figures for each thermomechanical treatment. The plastic strain anisotropy, which was consistent with the ... |
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| A REVIEW OF Ti-6A1-6V-2Sn FATIGUE BEHAVIOR. |
15 JUL 1970 |
113 pages |
| Authors:
Maurice F. Amateau; E. George Kendall; AEROSPACE CORP EL SEGUNDO CALIF LAB OPERATIONS
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| A compilation of Ti-6Al-6V-2Sn fatigue data is presented for a number of different material forms and conditions. Stress versus log cycles to failure (S-N) curves or master diagrams, or both, for annealed, solution-treated and aged, and thermomechanically worked materials are included. The data are organized according to material form, such as sheet, plate, rolled bar, forging, and extrusion. Crack propagation behavior in air and salt water is also included. The ... |
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| THE USE OF KNOOP HARDNESS TO DETERMINE THE YIELD LOCI OF Ti-6Al-4V, |
15 FEB 1970 |
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| Authors:
Maurice F. Amateau; Louis Raymond; AEROSPACE CORP EL SEGUNDO CALIF LAB OPERATIONS
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| Yield stress loci of Ti-6Al-4V processed to various degrees of anisotropy were determined from Knoop hardness numbers. Two methods of calculation were used, and the results were compared with uniaxial tensile values and Hill's theory of anisotropic yielding. Anisotropy ratios, expressed in terms of R values, were determined independently of the hardness method by strain measurements in the three principal directions. For the R values of 6 and greater, the ... |
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| THE BASAL TEXTURES OF Ti-6Al-4V PROCESSED BY VARIOUS METHODS, |
01 FEB 1970 |
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| Authors:
Dennis L. Dull; Maurice F. Amateau; AEROSPACE CORP EL SEGUNDO CALIF LAB OPERATIONS
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| Basal (0002) pole figures were determined for Ti-6Al-4V alloy processed by various thermomechanical treatments, such as rolling, solution treating, forging, and annealing. The treatment temperatures ranged from room temperature to 1725F. At 1725F, no significant difference in texture resulted from different treatments. At 1400F and room temperature, however, the type of treatment influenced the texture. (Author) |
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Reports by Author
