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Showing papers on "Metal matrix composite published in 1989"


Journal ArticleDOI
TL;DR: In this paper, the results of a study on the effects of matrix microstructure and particle distribution on the fracture of an aluminum alloy metal matrix composite containing 20% by volume SiC particulate were presented.
Abstract: This paper presents the results of a study on the effects of matrix microstructure and particle distribution on the fracture of an aluminum alloy metal matrix composite containing 20% by volume SiC particulate. The matrix microstructure was systematically varied by heat treating to either an under- or over-aged condition of equivalent strength, and was characterized using a combination of techniques. Quantitative metallographic techniques were utilized to characterize the material with respect to size, size distribution, and particle clustering, while transmission electron microscopy was utilized to characterize the details of the matrix microstructure in addition to the effects of aging on the character of the particle/matrix interfaces. Fracture experiments were conducted on smooth tensile, notched bend, shortrod toughness, and on specimens designed to permit controlled crack propagation, in an attempt to determine the effects of matrix microstructure and clustered regions on the details of damage accumulation. Large effects of microstructure on the notched properties were obtained with little effect of microstructure on tensile ductility. It is shown that the micromechanisms of fracture are significantly affected by the details of the matrix microstructure, interface character, and degree of clustering in the material. Fracture of the SiC was predominant in the underaged materials, with a preference for failure in the matrix and near the interface in the overaged material. Metallographic and fractographic analyses revealed that clustered regions were preferred sites for damage initiation in both the aging conditions tested, while preliminary results additionally indicate that damage accumulation ahead of a propagating crack also tended to occur in clustered regions.

332 citations


Journal ArticleDOI
TL;DR: In this article, a finite element analysis of the constitutive response of a 2124 Al-SiC whisker composite was presented, and the results of these calculations, as well as the predictions of several models for composite strengthening available in the literature, were compared with the experimental results.
Abstract: The precipitation characteristics, the mechanisms of accelerated aging, and the variation of uniaxial tensile stress-strain behavior in response to controlled variations in matrix microstructure were investigated for a 2124 AlSiC whisker composite. The yield strength of the composite was found to be independent of matrix aging condition. However, the overall ductility decreased monotonically with an increase in aging time. A finite element analysis of the constitutive response of the composite is presented. The results of these calculations, as well as the predictions of several models for composite strengthening available in the literature, were compared with the experimental results. The presence of brittle whiskers in aluminum leads to a significant build-up of hydrostatic stresses in the matrix during plastic deformation. Void formation in the matrix of the composite as well as at the whisker-matrix interface appears to play an important role in controlling the overall failure mechanisms. Transmission electron microscopy observations of void formation a whisker ends are described for composite specimens strained in tension at room temperature and at 300°C. A detailed discussion of matrix deformation and interfacial debonding is presented in an attempt to identify the origins of low ductility in discontinuously reinforced metal-ceramic composites.

229 citations


Journal ArticleDOI
TL;DR: In this article, the authors investigated the wear resistance of an alumina fiber-aluminum metal matrix composite system to wear by two-body abrasion and found that wear resistance ranges from almost two to six times that of the unreinforced matrix alloy.
Abstract: Investigations are reported of the response of an alumina fibre–aluminium metal matrix composite system to wear by two-body abrasion. The wear resistance of the composites was found to range from almost two to six times that of the unreinforced matrix alloy. A transition in wear behaviour was found for the various sizes of abrasive particle. With small particles, the wear resistance of the composite increased with increasing fibre volume fraction and the worn surfaces were relatively smooth. With larger particles, the wear resistance decreased with increasing fibre content above a certain level and, on the worn surfaces, fibre fracture and extensive debonding were observed at the fibre/matrix interface. The effect of abrasive particle size on this transition behaviour may be explained by a theoretical analysis of the fracture of a brittle fibre in a ductile matrix under point loading.MST/872

164 citations


Journal ArticleDOI
TL;DR: In this article, the precipitation behavior of aluminum 6061 alloy reinforced with 10 vol.% SiC whiskers of variable aspect ratio was studied experimentally, and the results were compared with the precipitation behaviour of a control aluminum alloy 6061 in the unstrained and plastically strained conditions.
Abstract: Accelerated aging in metal matrix composites (MMCs) can be attributed to an increased dislocation density in the vicinity of the reinforcements or to the matrix residual stress field near reinforcements. Both mechanisms aid the diffusion of solute atoms, thereby leading to more rapid precipatation. In this work, the precipitation behavior of aluminum 6061 alloy reinforced with 10 vol.% SiC whiskers of variable aspect ratio was studied experimentally. The results were compared with the precipitation behavior of a control aluminum alloy 6061 in the unstrained and plastically strained conditions. It was found that the strained control alloy, with approximately the same expended plastic work as the composite, showed a similar β′ precipitation rate and activation energy as the composite. On the contrary, the unstrained alloy had a much higher activation energy for precipitation. A theoretical model was developed to predict the rate of precipitation in the residual stress field of the matrix. This rate was compared with the rate of precipitation on a regular edge dislocation array. It was found that, for realistic values of fiber radii and dislocation densities (about 0.25–1 μm and 1013–1014m−2 respectively), both mechanisms give comparable precipitation rates. However, solute atoms flowing towards the matrix-fiber interface under the influence of the residual stress field on encountering matrix dislocations are trapped, thereby lowering the activation energy to that of precipitation on dislocations. It was concluded that, for MMCs with large fibers and high dislocation densities, dislocation generation is the principal contibutor to accelerated aging while, in MMCs with small fibers and low dislocation densities, the residual stress mechanism predominates. For intermediate fiber radii and dislocation densities, both mechanisms could be important although, in real MMCs, dislocations seem to play the dominant role.

129 citations


Patent
10 Jan 1989
TL;DR: In this article, an aluminum metal matrix composite is formed by hermetically sealing the second filler within the mold with a body of molten aluminum metal at moderate temperatures, e.g. about 900°C, without need of any other infiltration expedients.
Abstract: An aluminum metal matrix composite comprises an aluminum metal matrix embedding a second filler (2), such as a ceramic second filler, and is formed by contacting, for example, a molten aluminum metal (20) with a permeable mass of second filler (22) within a ceramic impervious mold (12) formed by growing a polycrystalline oxidation reaction product into a first filler. By hermetically sealing the second filler (22) within the mold (12) with a body of molten aluminum metal (20), the latter spontaneously infiltrates the mass of second filler (22) at moderate temperatures, e.g. about 900°C, without need of any other infiltration expedients. The molten mass containing the infiltrated ceramic filler is solidified to provide the metal matrix composite which may be recovered from the mold (12). Optionally, the solidification is carried out under bonding conditions including maintaining the solidi­fying material in direct contact with the ceramic mold, to provide the metal matrix composite joined to the mold, or a part thereof, as a structural component.

97 citations


Journal ArticleDOI
TL;DR: In this article, the authors summarize the scope of operations for both cast-and powder-based processing and identify processing issues which cause matrix-reinforcement interface and property variability in discontinuous metal matrix composites.
Abstract: Metal matrix composite materials which utilize discontinuous-type reinforcement undergo unit operations associated with ingot, powder or cast metal manufacturing in addition to their own unique operations. An attempt is made to summarize the scope of operations for both cast- and powder-based processing and identify processing issues which cause matrix-reinforcement interface and property variability in discontinuous metal matrix composites.

94 citations


Patent
05 Jan 1989
TL;DR: In this article, a net-shaped ceramic-reinforced aluminum matrix composite is formed by forming a permeable mass of ceramic material (10) with a defined surface boundary having a barrier, and contacting a molten aluminum-magnesium alloy (20) with the porous mass of the material in the presence of a gas comprising from about 10 to 100 % nitrogen, by volume, balance nonoxidizing gas, e.g. hydrogen or argon.
Abstract: A net shaped ceramic-reinforced aluminum matrix composite is formed by forming a permeable mass of ceramic material (10) with a defined surface boundary having a barrier, and contacting a molten aluminum-magnesium alloy (20) with the permeable mass of ceramic material (10) in the pre­sence of a gas comprising from about 10 to 100 % nitrogen, by volume, balance nonoxidizing gas, e.g. hydrogen or argon. Under these conditions, the molten alloy (20) spontaneously infiltrates the ceramic mass under normal atmospheric pressures until it reaches the barrier. A solid body of the alloy (20) can be placed adjacent to a permeable bedding of ceramic material (10) having a barrier, and brought to the molten state, preferably to at least about 700°C, in order to form the net shape aluminum matrix composite by infiltration. In addition to magnesium, auxiliary alloying elements may be employed with alu­minum. The resulting composite products may contain a discontinuous aluminum nitride phase in the aluminum matrix.

77 citations


Journal ArticleDOI
TL;DR: Tensile tests with superimposed hydrostatic pressures were performed on two types of metal matrix composite: 2014 Al with 20% SiC particles and 2124 Al with 14% SiCs whiskers.
Abstract: Tensile tests with superimposed hydrostatic pressures were performed on two types of metal matrix composite: 2014 Al with 20% SiC particles and 2124 Al with 14% SiC whiskers. In the materials with SiC particulate, the ductility increases rapidly with pressure and the mode of damage initiation is by particle fracture. Materials containing SiC whiskers exhibit a different fracture mode involving whisker matrix decohesion, and strain localization which results in shear fracture.

75 citations


Journal ArticleDOI
TL;DR: In this article, the microstructures of samples of Ti6A14V, which contain 10 vol. % particulate TiC and have been heat-treated at temperatures between 900 and 1050°C, have been characterised.

67 citations


Journal ArticleDOI
TL;DR: In this paper, preliminary studies were conducted on the laser processing of SiC/A356•Al alloy metal matrix composite (MMC) for such applications as welding/joining and cutting.
Abstract: Preliminary studies were conducted on the laser processing of SiC/A356‐Al alloy metal matrix composite (MMC) for such applications as welding/joining and cutting. The SiC/A356‐Al MMC was processed using several different laser specific energies. Microstructural observations after laser processing revealed that the extent of reinforced material (SiC)‐matrix (A356‐Al) reaction is directly proportional to the laser energy input. As energy input increased, SiC particle dissolution became greater and aluminum carbide formation increased in both size and quantity. It appears possible to control substantial change (physical and chemical) in SiC particles during processing by controlling the amount and mode of energy input.

53 citations


Patent
28 Sep 1989
TL;DR: In this article, a post-formation process treatment and a substantially contiguous modification treatment are proposed to modify the properties of a metal matrix composite body by a post formation process treatment, where at least a portion of the matrix metal of the body and/or the filler material are modified or altered during or after the formation process.
Abstract: The present invention relates to modifying the properties of a metal matrix composite body by a post formation process treatment and/or a substantially contiguous modification treatment. The post formation process treatment may be applicable to a variety of metal matrix composite bodies produced by various techniques, and is particularly applicable to modifying the properties of a metal matrix composite body produced by a spontaneous infiltration technique. The substantially contiguous modification process may also be used primarily in conjunction with metal matrix composite bodies produced according to a spontaneous infiltration technique. Particularly, at least a portion of the matrix metal of the metal matrix composite body and/or the filler material of the metal matrix composite body is modified or altered during and/or after the formation process.

Patent
13 Oct 1989
TL;DR: In this paper, the formation of a metal matrix composite body by the spontaneous infiltration of a molten matrix metal into a three-dimensionalally interconnected material was described, and the filler material contained within at least a portion of its porosity.
Abstract: The present invention relates to the formation of a metal matrix composite body by the spontaneous infiltration of a molten matrix metal into a three-dimensionally interconnected material. Moreover, the three-dimensionally interconnected material may contain filler material within at least a portion of its porosity. Particularly, an infiltration enhancer and/or an infiltration enhancer precursor and/or an infiltrating atmosphere are in communication with a filler material and/or a three-dimensionally interconnected material and/or a matrix metal at least at some point during the process, which permits molten matrix metal to spontaneously infiltrate the three-dimensionally interconnected material and any filler material contained within at least a portion of the porosity of the three-dimensionally interconnected material.

Patent
28 Sep 1989
TL;DR: In this article, a novel method for forming metal matrix composite bodies and novel products produced by the method is described, where a preform or filler material has included at least some matrix metal powder, which permits molten matrix metal to spontaneously infiltrate the filler material or preform.
Abstract: The present invention relates to a novel method for forming metal matrix composite bodies and novel products produced by the method. Particularly, a permeable mass of filler material or a preform has included therein at least some matrix metal powder. Moreover, an infiltration enhancer and/or an infiltration enhancer precursor and/or an infiltrating atmosphere are in communication with the filler material or a preform, at least at some point during the process, which permits molten matrix metal to spontaneously infiltrate the filler material or preform. The presence of powdered matrix metal in the preform or filler material reduces the relative volume fraction of filler material to matrix metal.

Journal ArticleDOI
TL;DR: In this paper, a comprehensive differential scanning calorimetric (DSC) investigation has been conducted on the precipitation and dissolution behaviour of SiC particulate-reinforced 7091 aluminium.
Abstract: A comprehensive differential scanning calorimetric (DSC) investigation has been conducted on the precipitation and dissolution behaviour of SiC particulate-reinforced 7091 aluminium. DSC is shown to be a particularly attractive experimental technique for developing new thermal and thermomechanical processes for aluminium-based metal matrix composites. These new processes are necessitated due to the deleterious effects that the SiC reinforcement causes on the aluminium matrix precipitation behaviour and the resultant ductility and fracture toughness properties. In this study the effects of SiC concentration and ageing temperatures, times, and sequences were evaluated. In addition to the unreinforced 7091 alloy, composites containing 10, 20 and 30 vol% particulate SiC were characterized. Identifications of specific phases involved in reactions detected with DSC were achieved by making direct correlations to previously published transmission electron microscopy studies. It was found that the presence of SiC in the aluminium significantly affects the solid state transformation kinetics of the 7091 aluminium matrix. Specifically, increasing the SiC concentration was found to decrease the temperatures at which GPI and GPII zones precipitate at their maximum rates and to increase the temperature at which GPI zones revert at maximum rate. The transition phase,η, and equilibrium phase,η, formation kinetics were observed to be insensitive to SiC concentration. Also, increasing the SiC concentration was seen to decrease the temperature at which the equilibrium phase dissolution occurred at its maximum rate. Transformation mechanics have been proposed which are consistent with these observations.

Patent
28 Sep 1989
TL;DR: In this paper, a metal matrix composite is constructed between at least two bodies having a similar or a different chemical composition, the metal matrix com-posite functioning as a bonding means which bonds or fixes the bodies together.
Abstract: The present invention relates to forming a metal matrix composite (3) between at least two bodies (1) having a similar or a different chemical composition, the metal matrix com­posite functioning as a bonding means which bonds or fixes the bodies (1) together. Particularly, a metal matrix composite is produced by a spontaneous infiltration tech­nique by providing a filler material (2) or preform with an infiltration enhancer and/or an infiltration enhancer pre­cursor and/or an infiltrating atmosphere, which are in com­munication with the filler material or preform at least at some point during the process. Molten matrix metal then spontaneously infiltrates the filler material or preform, whereby the metal matrix composite serves to bond together two or more bodies.

Patent
06 Sep 1989
TL;DR: An aluminum-based metal matrix composite is produced from a charge containing a rapidly solidifed aluminum alloy and particles of a reinforcing material present in an amount ranging from about 0.1 to 50 percent by volume of the charge as mentioned in this paper.
Abstract: An aluminum based metal matrix composite is produced from a charge containing a rapidly solidifed aluminum alloy and particles of a reinforcing material present in an amount ranging from about 0.1 to 50 percent by volume of the charge. The charge is ball milled energetically to enfold metal matrix material around each of the particles while maintaining the charge in a pulverant state. Upon completion of the ball milling step, the charge is consolidated to provide a powder compact having a formable, substantially void free mass. The mass is then subject to a heat treatment during which it is solutionized at a temperature above the solvus temperature of the alloy, quenched and age hardened at a temperature below the solvus temperature of the allow to promote precipitation of a primary strenthening Al3(Li, Zr) phase and to precipitate substantially all of the Al3(Li, Zr) phase into the metal matrix. The composite is especially suited for use in aerospace, automotive, electronic, wear resistance critical components and the like.

Patent
09 Jan 1989
TL;DR: An aluminum-based metal matrix composite is produced from a charge containing a rapidly solidified aluminum alloy and particles of a reinforcing material present in an amount ranging from about 0.1 to 50 percent by volume of the charge.
Abstract: An aluminum based metal matrix composite is produced from a charge containing a rapidly solidified aluminum alloy and particles of a reinforcing material present in an amount ranging from about 0.1 to 50 percent by volume of the charge. The charge is ball milled energetically to enfold metal matrix material around each of the particles while maintaining the charge in a pulverulant state. Upon completion of the ball milling step, the charge is consolidated to provide a powder compact having a formable, substantially void free mass. The compact is especially suited for use in aerospace, automotive, electronic, wear resistance critical components and the like.

Journal ArticleDOI
TL;DR: In this article, a finite element based procedure is presented which accounts for micromechanical nonlinear behavior of the matrix material in continuous fiber reinforced composites, which is a periodic hexagonal array of elastic fibers embedded in an elastic-plastic matrix material.

Patent
16 Aug 1989
TL;DR: In this article, the porosity of a metal matrix composite material was measured by causing ultrasonic waves to propagate through a specimen, and measuring both the wave velocity and attenuation in the specimen.
Abstract: The mechanical properties of a metal matrix composite material e.g. a bar 12 depend upon both the proportion of filler and the proportion of voids or pores. The filler proportion and the porosity can be assessed non-destructively by causing ultrasonic waves to propagate through a specimen, and measuring both the wave velocity and attenuation in the specimen. These measured values are compared (for example graphically) with those obtained with material of known filler volume fraction and porosity, and hence the unknown values determined. The apparatus 10 includes a tank 14 containing water 16 (as a coupling fluid). The tank has leaky seals 18. Two transducers 20, 22 are provided and a computer 24 is used to provide the results.

Book ChapterDOI
TL;DR: An integrated set of experimental techniques for mechanical and thermal testing of the Ti3Al/SCS-6 metal matrix composite is presented in this article, where a modified version of an existing quartz lamp heating system allows temperature control at multiple points on the specimen.
Abstract: An integrated set of experimental techniques for mechanical and thermal testing of the Ti3Al/SCS-6 metal matrix composite is presented. Areas of discussion include gripping, specimen design, specimen heating, temperature measurement, and displacement measurement. The grip system was originally developed for use with ceramic composite materials and works well with the relatively brittle titanium-aluminide matrix composite used in this study. A modified version of an existing quartz lamp heating system allows temperature control at multiple points on the specimen. Results from baseline tension tests at various temperatures and post-thermal cycling tension tests are presented.

Journal ArticleDOI
TL;DR: In this paper, the crack propagation characteristics of specimens of a unidirectionally reinforced α-Al2O3/Mg alloy metal matrix composite were investigated by means of fatigue crack propagation tests, tensile tests and fracture toughness tests.
Abstract: The crack propagation characteristics of specimens of a unidirectionally reinforced α-Al2O3/Mg alloy metal matrix composite were investigated by means of fatigue crack propagation tests, tensile tests and fracture toughness tests. Samples were tested in longitudinal and transverse orientations. Fatigue crack propagation rates were successfully measured for each orientation. Crack propagation modes were found to be dependent upon the applied stress intensity and the fibre orientation. The crack propagation rates can vary by several orders of magnitude between nominally identical samples. In thermal cycling tests, voids were nucleated at the fibre/matrix interface: these voids decreased the load-carrying capability of the metal matrix composite but increased the work of fracture in the longitudinal orientation.

01 Aug 1989
TL;DR: In this paper, a computer program was written to minimize the residual stress in the matrix subject to the interface material properties, such as interface modulus, thickness and thermal expansion coefficient.
Abstract: Due to the thermal expansion coefficient mismatch (CTE) between the fiber and the matrix, high residual sresses exist in metal matrix composite systems upon cool down from processing temperature to room temperature. An interface material can be placed between the fiber and the matrix to reduce the high tensile residual stresses in the matrix. A computer program was written to minimize the residual stress in the matrix subject to the interface material properties. The decision variables are the interface modulus, thickness and thermal expansion coefficient. The properties of the interface material are optimized such that the average distortion energy in the matrix and the interface is minimized. As a result, the only active variable is the thermal expansion coefficient. The optimum modulus of the interface is always the minimum allowable value and the interface thickness is always the maximum allowable value, independent of the fiber/matrix system. The optimum interface thermal expansion coefficient is always between the values of the fiber and the matrix. Using this analysis, a survey of materials was conducted for use as fiber coatings in some specific composite systems.

Patent
07 Nov 1989
TL;DR: In this article, a self-generated vacuum is used for forming net or near net-shape metal matrix composite bodies, where a molten matrix metal is in contact with a filler material or a preform.
Abstract: The present invention relates to a novel process for forming net or near net-shape metal matrix composite bodies Particularly, a molten matrix metal is in contact with a filler material or a preform in the presence of a reactive atmosphere, at least at some point during the process, which permits molten matrix metal to react, at least partially or substantially completely, with the reactive atmosphere, thereby causing molten matrix metal to infiltrate the filler material or preform due to the creation of a self-generated vacuum Forming a glassy seal on the reaction system, the self-generated vacuum infiltration occurs without the application of any external pressure or vacuum The molten matrix metal infiltrates the filler material up to at least a portion of a provided barrier means

Journal ArticleDOI
TL;DR: In this paper, a review of mathematical models designed to predict the mechanical properties of MMCs from a knowledge of the properties of the constituents and their geometry is presented and a brief review is also included.
Abstract: Test procedures for selected property measurements on metal matrix composite (MMC) materials are examined. The mechanical properties considered are associated with tensile, compressive, bend, impact, fracture toughness, fatigue, and high temperature testing. A brief review is also included of mathematical models designed to predict the mechanical properties of MMCs from a knowledge of the properties of the constituents and their geometry.MST/846

Patent
18 Oct 1989
TL;DR: In this paper, a gas-metal arc deposition of metal, metal alloys, and metal matrix composites is described, where a suspension of particulates in an inert gas enters the deposition chamber via a plurality of feed openings below and around the orifice so that reinforcing particulates join the metal droplets.
Abstract: Method and apparatus for gas-metal arc deposition of metal, metal alloys, and metal matrix composites. The apparatus contains an arc chamber for confining a D.C. electrical arc discharge, the arc chamber containing an outlet orifice in fluid communication with a deposition chamber having a deposition opening in alignment wiht the orifice for depositing metal droplets on a coatable substrate. Metal wire is passed continuously into the arc chamber in alignment with the orifice. Electric arcing between the metal wire anode and the orifice cathode produces droplets of molten metal from the wire which pass through the orifice and into the deposition chamber for coating a substrate exposed at the deposition opening. When producing metal matrix composites, a suspension of particulates in an inert gas enters the deposition chamber via a plurality of feed openings below and around the orifice so that reinforcing particulates join the metal droplets to produce a uniform mixture which then coats the exposed substrate with a uniform metal matrix composite.

Patent
28 Feb 1989
TL;DR: In this paper, a method for producing a corrosion and mechanical wear resistant coating on a metal surface to be protected by means of a flame spraying or arc spraying process is described, which results in a coating of improved adhesion and low porosity.
Abstract: A method is described for producing a corrosion and mechanical wear resistant coating on a metal surface to be protected. The method comprises (a) providing a rod or wire formed of a metal matrix composite comprising a metal matrix having distributed therein a finely divided solid filler material and (b) applying a coating of said metal matrix composite on said metal surface to be protected by means of a flame spraying or arc spraying process. This results in a coating of improved adhesion and low porosity.

01 Jul 1989
TL;DR: In this paper, the influence of in situ matrix strength and the interphase degradation on the unidirectional composite stress-strain behavior is examined, which may be helpful in resolving discrepancies between experimentally observed composite behavior and predicted response.
Abstract: Recent efforts in computational mechanics methods for simulating the nonlinear behavior of metal matrix composites have culminated in the implementation of the Metal Matrix Composite Analyzer (METCAN) computer code. In METCAN material nonlinearity is treated at the constituent (fiber, matrix, and interphase) level where the current material model describes a time-temperature-stress dependency of the constituent properties in a material behavior space. The composite properties are synthesized from the constituent instantaneous properties by virtue of composite micromechanics and macromechanics models. The behavior of metal matrix composites depends on fabrication process variables, in situ fiber and matrix properties, bonding between the fiber and matrix, and/or the properties of an interphase between the fiber and matrix. Specifically, the influence of in situ matrix strength and the interphase degradation on the unidirectional composite stress-strain behavior is examined. These types of studies provide insight into micromechanical behavior that may be helpful in resolving discrepancies between experimentally observed composite behavior and predicted response.

Journal ArticleDOI
TL;DR: In this paper, a metal matrix composite, consisting of a dispersion of Saffil alumina fibres in an aluminium alloy casting (Al-6Si-2Cu), has been produced using a flow-cast semi-liquid metal matrix.

Patent
13 Oct 1989
TL;DR: In this paper, a preform material is placed onto the surface of or into a matrix metal alloy, whereupon the matrix metal Alloy spontaneously infiltrates the preform and sinks into the supply.
Abstract: The present invention relates to a novel method for forming metal matrix composite bodies. Particularly, a permeable mass of filler material is formed into a preform. The preform material can then be placed onto the surface of or into a matrix metal alloy, whereupon the matrix metal alloy spontaneously infiltrates the preform. After substantial complete infiltration of the preform, the preform begins to at least partially sink into the matrix metal alloy supply. The matrix metal Which has infiltrated the preform is then allowed to cool, thus forming a metal matrix composite body.

Journal ArticleDOI
J White1, T.C. Willis1
TL;DR: In this article, the production of metal matrix composite (MMC) systems using the technique of spray co-deposition is described, and the properties of three MMC systems are compared with those of the respective unreinforced alloys and the advantages of spray deposition as a method of producing MMC materials is discussed.