scholarly journals Carbide Nanoparticle Dispersion Techniques for Metal Powder Metallurgy

Metals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 871
Author(s):  
Bahrum Prang Rocky ◽  
Christopher R. Weinberger ◽  
Steven R. Daniewicz ◽  
Gregory B. Thompson
Keyword(s):  
Metal Matrix ◽  
Matrix Material ◽  
High Energy ◽  
Mixing Process ◽  
Nanoparticle Dispersion ◽  
Mechanochemical Processing ◽  
Powder Mixing ◽  
Iron Powders ◽  
Uniform Dispersion ◽  
Alcohol Solvent

Nanoparticles (NP) embedded into a matrix material have been shown to improve mechanical properties such as strength, hardness, and wear-resistance. However, the tendency of NPs to agglomerate in the powder mixing process is a major concern. This study investigates five different mechanochemical processing (MCP) routes to mitigate agglomeration to achieve a uniform dispersion of ZrC NPs in an Fe-based metal matrix composite. Our results suggest that MCP with only process controlling agents is ineffective in avoiding aggregation of these NPs. Instead, the uniformity of the carbide NP dispersion is achieved by pre-dispersing the NPs under ultrasonication using suitable surfactants followed by mechanically mixing of the NPs with iron powders in an alcohol solvent which is then dried. High-energy MCP is then used to embed the NPs within the powders. These collective steps resulted in a uniform dispersion of ZrC in the sintered (consolidated) Fe sample.

Quality Features of Metal Matrix Composite Castings

2013 ◽  
Vol 58 (3) ◽  
pp. 659-662 ◽  
Author(s):  
K. Gawdzińska
Keyword(s):  
Metal Matrix Composite ◽  
Matrix Composite ◽  
Metal Matrix ◽  
Matrix Material ◽  
Quality Characteristics ◽  
Material Quality ◽  
Reinforcement Material ◽  
Composite Casting ◽  
Quality Features

Abstract In this paper it is stated, that a set of quality features of metal matrix composite castings differs from the same set for castings of classic materials, although some features are common for both of these material groups. These features (pertaining to a set of quality characteristics of composite castings) have been named as specific, they have not been determined yet and a description of material quality should be performed (according to the qualitology) on a principle of description of quality characteristics of this product. Therefore, this set of features has been determined. It was proposed to add the following characteristics to the set of specific features of composite castings quality: matrix material, reinforcement material, binding between components and porosity of the composite casting. In this set a sub-set of quality characteristics of composite castings was also determined.

scholarly journals Achieving high strength and ductility in ODS-W alloy by employing oxide@W core-shell nanopowder as precursor

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Zhi Dong ◽  
Zongqing Ma ◽  
Liming Yu ◽  
Yongchang Liu
Keyword(s):  
High Temperature ◽  
Metal Matrix ◽  
High Performance ◽  
High Energy ◽  
Core Shell ◽  
Microstructural Stability ◽  
Oxide Particles ◽  
Ods Alloy ◽  
Prepared Alloy ◽  
Strength And Ductility

AbstractWith excellent creep resistance, good high-temperature microstructural stability and good irradiation resistance, oxide dispersion strengthened (ODS) alloys are a class of important alloys that are promising for high-temperature applications. However, plagued by a nerve-wracking fact that the oxide particles tend to aggregate at grain boundary of metal matrix, their improvement effect on the mechanical properties of metal matrix tends to be limited. In this work, we employ a unique in-house synthesized oxide@W core-shell nanopowder as precursor to prepare W-based ODS alloy. After low-temperature sintering and high-energy-rate forging, high-density oxide nanoparticles are dispersed homogeneously within W grains in the prepared alloy, accompanying with the intergranular oxide particles completely disappearing. As a result, our prepared alloy achieves a great enhancement of strength and ductility at room temperature. Our strategy using core-shell powder as precursor to prepare high-performance ODS alloy has potential to be applied to other dispersion-strengthened alloy systems.

Finite Element Modeling for Prediction of Residual Stresses in Fiber Reinforced Metal Matrix Composites

1993 ◽  
Author(s):  
Partha Rangaswamy ◽  
N. Jayaraman
Keyword(s):  
Residual Stress ◽  
Finite Element ◽  
Residual Stresses ◽  
Metal Matrix Composites ◽  
Metal Matrix ◽  
Matrix Material ◽  
Unit Cell ◽  
Experimental Results ◽  
Matrix Composites ◽  
Layer Removal

Abstract In metal matrix composites residual stresses developing during the cool-down process after consolidation due to mismatch in thermal expansion coefficients between the ceramic fibers and metal matrix have been predicted using finite element analysis. Conventionally, unit cell models consisting of a quarter fiber surrounded by the matrix material have been developed for analyzing this problem. Such models have successfully predicted the stresses at the fiber-matrix interface. However, experimental work to measure residual stresses have always been on surfaces far away from the interface region. In this paper, models based on the conventional unit cell (one quarter fiber), one fiber, two fibers have been analyzed. In addition, using the element birth/death options available in the FEM code, the surface layer removal process that is conventionally used in the residual stress measuring technique has been simulated in the model. Such layer removal technique allows us to determine the average surface residual stress after each layer is removed and a direct comparison with experimental results are therefore possible. The predictions are compared with experimental results of an eight-ply unidirectional composite with Ti-24Al-11 Nb as matrix material reinforced with SCS-6 fibers.

Nickel/Alumina Metal Matrix Nanocomposites Obtained by High-Energy Ball Milling and Spark Plasma Sintering

2018 ◽  
Author(s):  
Enrique Martínez-Franco ◽  
Ming Li ◽  
Ricardo Cuenca Álvarez ◽  
Jesús González Hernández ◽  
Chao Ma ◽  
...  
Keyword(s):  
Ball Milling ◽  
Spark Plasma Sintering ◽  
Metal Matrix ◽  
High Energy ◽  
Alumina Nanoparticles ◽  
Metal Matrix Nanocomposites ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
Energy Ball ◽  
Matrix Nanocomposites

Metal matrix nanocomposites (MMNCs) are anticipated to offer significantly better performance than existing superalloys. Nickel/alumina nanocomposite samples were fabricated with a powder metallurgy method, combining high-energy ball milling (HEBM) and spark plasma sintering (SPS). The objective of this research is to determine the effect of alumina nanoparticle fraction and HEBM parameters on the powder preparation and sintering processes, and resultant microstructure and properties. Nickel-based powders containing various fractions (1, 5 and 15 vol.%) alumina nanoparticles were prepared by HEBM. The initial particle sizes were 44 μm and 50 nm for nickel and alumina, respectively. The milling process was conducted by starting with mixing at 250 rpm for 5 min, followed by cycling operation at high and low speeds (1200 rpm for 4 min and 150 rpm for 1 min). Samples at different milling times (30, 60, 90 and 120 min) of each composition were obtained. Scanning electron microscopy (SEM) was used to evaluate the dispersion of nanoparticles in the powders at different milling times. SPS technique was used for consolidation of the prepared powders. SEM images showed that alumina nanoparticles are homogeneously dispersed in the metal matrix in the sample containing 15 vol.% alumina. Hardness measurements in cross sections of SPSed samples showed higher values for Ni/Al2O3 MMNC compared to pure Ni.

Investigation Techniques of In Situ AlMg/AlN Metal Matrix Composites via Reactive Gas Injection

2013 ◽  
Vol 837 ◽  
pp. 283-289 ◽  
Author(s):  
Raluca Maria Florea ◽  
Oana Bălţătescu ◽  
Aurelian Buzăianu ◽  
Ioan Carcea
Keyword(s):  
Metal Matrix ◽  
Gas Flow ◽  
Sem Analysis ◽  
Critical Parameters ◽  
Matrix Composites ◽  
Uniform Dispersion ◽  
Liquid Systems ◽  
Spontaneous Infiltration ◽  
Reactive Gas

In this paper characteristics of an AlMg/AlN composite produced in-situ and processed in a flowing N2 atmosphere is investigated. Some critical parameters such as the manufacturing process temperature, the percentage of the magnesium consumed, the flowing reactive gas flow and the time for completing the manufacturing are considered as variables for the parametric investigation. Moreover, the effect of different amount of Mg employed has been also investigated, since Mg acts as a catalyst at the surface both for the gas/liquid and solid/liquid systems. Traditional methods were used for the basic characterization of the composite. The microstructure of the composite was investigated by optical and scanning electron microscopy (OM, SEM). SEM analysis was performed in order to observe the microstructural evolution as a function of the Mg content and to identify some reasons of the presence of porosity or any irregularities within the metal matrix. The evolution of mechanical properties, in terms of microhardness, at different percentage of Mg were monitored. By EDS technique the distribution of the elements was obtained. Furthermore, employing an optimization process, uniform dispersion of the strengthening (AlN) particles in the metal matrix with homogeneous properties along the composite material is obtained. Based on the aforementioned statements, it can be concluded that the reactions between Al, Mg and the N2 atmosphere induce spontaneous infiltration in the metal matrix. The complete mix of properties and experimentally assessed parameters can be used for industrial purpose manufacturing design and development.

Initial Stages of InAs Quantum Dots Evolution in GaAs/AlAs Matrixes

2002 ◽  
Vol 749 ◽  
Author(s):  
Michael Yakimov ◽  
Vadim Tokranov ◽  
Alex Katnelson ◽  
Serge Oktyabrsky
Keyword(s):  
Quantum Dots ◽  
Direct Evidence ◽  
Matrix Material ◽  
Single Layer ◽  
High Energy ◽  
Inas Quantum Dots ◽  
Auger Signal ◽  
The Matrix ◽  
Growth Evolution

ABSTRACTWe have studied the first phases of post-growth evolution of InAs quantum dots (QDs) using in-situ Auger electron spectroscopy in conjunction with Reflection High Energy Electron Diffraction (RHEED). Direct evidence for InAs intermixing with about 6ML (monolayers) of the matrix material is found from Auger signal behavior during MBE overgrowth of InAs nanostructures. Re-establishment of 2D growth mode by overgrowth with GaAs or AlAs was monitored in single-layer and multi-layer QD structures using RHEED. Decay process of InAs QDs on the surface is found to have activation energy of about 1.1 eV that corresponds to In intermixing with the matrix rather than evaporation from the surface.

scholarly journals In Situ Stress Tensor Determination during Phase Transformation of a Metal Matrix Composite by High-Energy X-ray Diffraction

Materials ◽  
2018 ◽  
Vol 11 (8) ◽  
pp. 1415 ◽  
Author(s):  
Guillaume Geandier ◽  
Lilian Vautrot ◽  
Benoît Denand ◽  
Sabine Denis
Keyword(s):  
Phase Transformation ◽  
Stress Tensor ◽  
Metal Matrix Composite ◽  
Matrix Composite ◽  
Metal Matrix ◽  
High Energy ◽  
X Ray Diffraction ◽  
Synchrotron Source ◽  
X Ray

In situ high-energy X-ray diffraction using a synchrotron source performed on a steel metal matrix composite reinforced by TiC allows the evolutions of internal stresses during cooling to be followed thanks to the development of a new original experimental device (a transportable radiation furnace with controlled rotation of the specimen). Using the device on a high-energy beamline during in situ thermal treatment, we were able to extract the evolution of the stress tensor components in all phases: austenite, TiC, and even during the martensitic phase transformation of the matrix.

scholarly journals Extraction of void fraction in metal matrix composite using morphological image processing

1994 ◽  
Vol 3 (2) ◽  
pp. 096369359400300
Author(s):  
Lun X. He ◽  
David K. Hsu ◽  
John P. Basart
Keyword(s):  
Image Processing ◽  
Void Fraction ◽  
Metal Matrix ◽  
Volume Fraction ◽  
Matrix Material ◽  
Void Content ◽  
Matrix Composites ◽  
Cross Sectional ◽  
Morphological Image Processing ◽  
The Matrix

In continuous fiber reinforced metal matrix composites, the volume fraction of voids in the matrix material is an important parameter for material property characterization. In analyzing a cross-sectional micrograph of such a composite, the presence of fiber images and voids occurring on the perimeter of fibers complicates the determination of void content. This paper describes image processing steps using mathematical morphology for the extraction of void fraction in a composite.

Research on the Repair Performance of Self-Healing Aluminum Material Based on the Low Melting Point Slicker Solder Alloy

2018 ◽  
Vol 932 ◽  
pp. 57-61
Author(s):  
Wei Sun ◽  
Rong Xin Yan ◽  
Li Chen Sun ◽  
Zheng Li ◽  
Guan Qing Lang ◽  
...  
Keyword(s):  
Aluminum Alloy ◽  
Melting Point ◽  
Matrix Material ◽  
High Energy ◽  
The Self ◽  
Al Alloy ◽  
Self Healing ◽  
Material Technology ◽  
Damage Repair ◽  
Aluminum Alloy 6063

It is great significance to study self-healing aluminum alloy materials for spacecraft the structure protection from high energy space weapon attack and debris impact in future. In this paper, Using aluminum alloy (6063) as matrix material with low melting point alloy (Sn60Pb40, the melting point of 183°C) as repairing materials, the self-healing Aluminum Alloy material was designed and manufactured by the smelting and casting method. The crack damage repair performance of the self-healing Al alloy was researched through the experiment. The results show that the self-healing aluminum alloy has certain self-healing ability without help, when the temperature reaches the melting point temperature of Sn60Pb40. The repair time is about 20min, the crack filling rate can reach 84%. The research conclusion can provide a reference for the development of metal self-healing material technology.

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