Thermodynamic analysis of chemical compatibility of ceramic reinforcement materials with niobium aluminides

1990 ◽  
Vol 5 (7) ◽  
pp. 1561-1566 ◽  
Author(s):  
Ajay K. Misra
Keyword(s):  
Matrix Composites ◽  
Key Factors ◽  
Intermetallic Matrix ◽  
Reinforcement Material ◽  
The Matrix ◽  
Intermetallic Matrix Composites ◽  
Niobium Aluminide ◽  
Niobium Aluminides ◽  
Ceramic Reinforcement ◽  
Selection Of

Niobium aluminide-based intermetallic matrix composites are currently being considered as potential high-temperature structural materials. One of the key factors in the selection of a reinforcement material is its chemical stability in the matrix. In this study, chemical interactions between two niobium aluminides, Nb3Al and Nb2Al, and several potential ceramic reinforcement materials, which include carbides, borides, nitrides, and oxides, were analyzed from thermodynamic considerations. Several thermodynamically stable reinforcement materials have been identified for these two matrices.

Processing and Properties of Intermetallic Matrix Composites

1990 ◽  
Vol 213 ◽  
Author(s):  
D.E. Alman ◽  
N.S. Stoloff
Keyword(s):  
Mechanical Properties ◽  
Injection Molding ◽  
Matrix Composites ◽  
Intermetallic Matrix ◽  
Processing Variables ◽  
Processing Effects ◽  
Intermetallic Matrix Composites ◽  
Selection Of

ABSTRACTThis paper is concerned with the processing and mechanical properties of intermetallic-matrix composites. The effects of processing variables on fabrication of compounds including Ni3Al, NiAl, TiTaAl2, MoSi2 and their composites is described. A key concern is with processing effects on microstructure, selection of compatible ceramic reinforcing phases, and whisker alignment through injection molding.

Particulate Intermetallic Matrix Composite Made by One-Step Pulsed Laser Deposition

1992 ◽  
Vol 273 ◽  
Author(s):  
Li-Chyong Chen ◽  
Ernest L. Hall ◽  
Karen A. Lou
Keyword(s):  
Laser Ablation ◽  
Pulsed Laser Deposition ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
Matrix Composites ◽  
Intermetallic Matrix ◽  
Optical Films ◽  
The Matrix ◽  
One Step ◽  
Intermetallic Matrix Composites

ABSTRACTA novel way of producing particulate intermetallic matrix composites based on Nb-Al in one step using pulsed laser deposition (PLD) has been investigated. One unique characteristic, inherent to laser ablation, is the generation of particulates. These particulates condense on the substrate and become part of the film. In some cases, such as in high Tc superconducting or optical films applications, it is believed that the presence of particulates diminishes the quality of the films. In this work, we demonstrate that it can be advantageous in some applications to incorporate these particulates into the films.Nb-Al films were prepared by laser ablation from a Nb3Al target using a 248nm KrF excimer laser at various fluences and substrate temperatures. Transmission (TEM) and scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), and Auger electron spectroscopy (AES) were used to characterize the samples. The resultant films consist of a homogeneous matrix with uniformly distributed inclusions. The size of the particles generated by PLD is in the range of a few tens of nanometers to a few microns. EDX shows that the matrix has a composition of Nb7A13 and the particulates contain barely detectable Al. The mechanism of the depletion of Al in the particulates will be discussed. The merit of having a ductile Nb phase embedded in the intermetallic matrix is evident as the cracks generated during TEM sample thinning process propagate in the brittle matrix and finally are arrested at the ductile inclusions.

MECHANICAL PROPERTIES OF IN-SITUFeAl-TiB2 INTERMETALLIC MATRIX COMPOSITES

2009 ◽  
Vol 23 (06n07) ◽  
pp. 1479-1484 ◽  
Author(s):  
JONGHOON KIM ◽  
BONGGYU PARK ◽  
YONGHO PARK ◽  
IKMIN PARK ◽  
HEESOO LEE
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Matrix Composites ◽  
Intermetallic Matrix ◽  
Arc Melting ◽  
The Matrix ◽  
Matrix Reinforcement ◽  
Intermetallic Matrix Composites ◽  
Properties Of Composites

Intermetallic matrix composites reinforced with ceramic particles have received a great deal of attention. Iron aluminide is known to be a good material for the matrix in such composites. Two processes were used to fabricate FeAl - TiB 2 intermetallic matrix composites. One was liquid melt in-situ mixing, and the other was arc melting and suction casting processes. FeAl - TiB 2 IMCs obtained by two different methods were investigated to elucidate the influence of TiB 2 content. In both methods, the grain size in the FeAl alloy decreased with the presence of titanium diboride. The grain size of in-situ FeAl - TiB 2 IMCs became smaller than that of arc FeAl - TiB 2 IMCs. Significant increase in fracture stress and hardness was achieved in the composites. The in-situ process gives clean, contamination-free matrix/reinforcement interface which maintained good bonding causing high load bearing capability. This contributed to the increase in the mechanical properties of composites.

Deformation at interfaces of Ti-6Al-4V/SiC fiber composites

1992 ◽  
Vol 50 (1) ◽  
pp. 158-159
Author(s):  
Warren J. Moberly ◽  
Daniel B. Miracle ◽  
S. Krishnamurthy
Keyword(s):  
Thermal Stresses ◽  
Load Transfer ◽  
Coefficient Of Thermal Expansion ◽  
Hot Isostatic Pressing ◽  
Matrix Composites ◽  
Ongoing Research ◽  
Aerospace Applications ◽  
Sic Fiber ◽  
The Matrix ◽  
Intermetallic Matrix Composites

Titanium-aluminum alloy metal matrix composites (MMC) and Ti-Al intermetallic matrix composites (IMC), reinforced with continuous SCS6 SiC fibers are leading candidates for high temperature aerospace applications such as the National Aerospace Plane (NASP). The nature of deformation at fiber / matrix interfaces is characterized in this ongoing research. One major concern is the mismatch in coefficient of thermal expansion (CTE) between the Ti-based matrix and the SiC fiber. This can lead to thermal stresses upon cooling down from the temperature incurred during hot isostatic pressing (HIP), which are sufficient to cause yielding in the matrix, and/or lead to fatigue from the thermal cycling that will be incurred during application, A second concern is the load transfer, from fiber to matrix, that is required if/when fiber fracture occurs. In both cases the stresses in the matrix are most severe at the interlace.

Microstructural characterization of plasma-processed Ti-Al metal matrix composites

1989 ◽  
Vol 47 ◽  
pp. 552-553
Author(s):  
M. G. Burke ◽  
M. N. Gungor ◽  
M. A. Burke
Keyword(s):  
High Temperature ◽  
Titanium Aluminide ◽  
Plasma Processing ◽  
Microstructural Characterization ◽  
High Temperature Strength ◽  
Matrix Composites ◽  
Intermetallic Matrix ◽  
Long Time ◽  
Strength And Stiffness ◽  
Intermetallic Matrix Composites

Intermetallic matrix composites are candidates for ultrahigh temperature service when light weight and high temperature strength and stiffness are required. Recent efforts to produce intermetallic matrix composites have focused on the titanium aluminide (TiAl) system with various ceramic reinforcements. In order to optimize the composition and processing of these composites it is necessary to evaluate the range of structures that can be produced in these materials and to identify the characteristics of the optimum structures. Normally, TiAl materials are difficult to process and, thus, examination of a suitable range of structures would not be feasible. However, plasma processing offers a novel method for producing composites from difficult to process component materials. By melting one or more of the component materials in a plasma and controlling deposition onto a cooled substrate, a range of structures can be produced and the method is highly suited to examining experimental composite systems. Moreover, because plasma processing involves rapid melting and very rapid cooling can be induced in the deposited composite, it is expected that processing method can avoid some of the problems, such as interfacial degradation, that are associated with the relatively long time, high temperature exposures that are induced by conventional processing methods.

The Mechanics and Mechanical Behavior of High-Temperature Intermetallic Matrix Composites

2000 ◽  
Author(s):  
Ronald Gibala ◽  
Amit K. Ghosh ◽  
David J. Srolovitz ◽  
John W. Holmes ◽  
Noboru Kikuchi
Keyword(s):  
High Temperature ◽  
Mechanical Behavior ◽  
Matrix Composites ◽  
Intermetallic Matrix ◽  
Intermetallic Matrix Composites

scholarly journals Comparison of NDE Results and Correlation With Microstructural Characteristics of NiFeAl/Wf

1994 ◽  
Author(s):  
David K. Hsu ◽  
Peter K. Liaw ◽  
George Y. Baaklini
Keyword(s):  
Quality Assurance ◽  
Nondestructive Evaluation ◽  
Metal Matrix ◽  
Complex Structure ◽  
Matrix Composites ◽  
Fiber Density ◽  
Microstructural Characteristics ◽  
X Ray ◽  
Intermetallic Matrix ◽  
Intermetallic Matrix Composites

Metal matrix composites (MMC) and intermetallic matrix composites (IMC) are materials of complex structure. Nominally defect-free, as-manufactured MMC requires nondestructive evaluation (NDE) for quality assurance and process monitoring purposes. In this work, three NDE techniques — ultrasonics, eddy current, and X-ray radiography — were applied to un-damaged NiFeAI/Wf coupons. Images of the coupons were obtained using the three techniques. The NDE results were compared among themselves, and correlations were sought between these results and microstructural features of the specimen. Consistencies were found among the NDE results and a strong correlation was found between the spatial variation of fiber density and the NDE signals.

Transmission Electron Microscope Specimen Preparation of Metal Matrix Composites Using the Focused Ion Beam Miller

2000 ◽  
Vol 6 (5) ◽  
pp. 452-462 ◽  
Author(s):  
Julie M. Cairney ◽  
Robert D. Smith ◽  
Paul R. Munroe
Keyword(s):  
Electron Microscope ◽  
Metal Matrix Composites ◽  
Transmission Electron Microscope ◽  
Metal Matrix ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Matrix Composites ◽  
Transmission Electron ◽  
The Matrix ◽  
Ceramic Reinforcement

AbstractTransmission electron microscope samples of two types of metal matrix composites were prepared using both traditional thinning methods and the more novel focused ion beam miller. Electropolishing methods were able to produce, very rapidly, thin foils where the matrix was electron transparent, but the ceramic reinforcement particles remained unthinned. Thus, it was not possible in these foils to study either the matrix-reinforcement interface or the microstructure of the reinforcement particles themselves. In contrast, both phases in the composites prepared using the focused ion beam miller thinned uniformly. The interfaces in these materials were clearly visible and the ceramic reinforcement was electron transparent. However, microstructural artifacts associated with ion beam damage were also observed. The extent of these artifacts and methods of minimizing their effect were dependent on both the materials and the milling conditions used.

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