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Showing 1 to 20 of 44 for “"Mechanical Alloying"”.
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Consolidation of WC-Co nanocomposites synthesised by mechanical alloying
The influence of mechanical alloying (MA) milling time, temperature, sintering method and microstructure on the mechanical properties of a tungsten carbide-cobalt (WC-Co) hardmetal, based on 10wt% Co, has been established. The effects of high-energy milling for 30, 60, 180 and 300 min and the …
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Polymer blends formed by the solid state mechanical alloying process
… and co-workers. This novel technique, called Mechanical Alloying (MA), involves the repeated welding, working hardening, and fracture of metallic powders to form an alloy. The research presented in this thesis describes the use of the MA process to form polymer blends. Until recently there has …
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Additive Manufacturing of Aluminium-Metal Matrix Composite developed through Mechanical Alloying
… of the process, material microstructure and mechanical properties is important for its adoption as a manufacturing route of Aluminium Metal Matrix Composites. The effect of the processing parameters (time and speed) on embedding the Silicon Carbide onto the surface of the AlSi10Mg alloy was …
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Dispersion and Integration of Dopants by Mechanical Alloying in Complex Hydrogen Storage Materials
Prior work had found that MgH2, a thermodynamically hindered system, can be destabilized through the introduction of Si but no microstructural information has been presented. In this work, confirmation of the proposed forward dehydriding mechanism to Mg2Si was obtained in the MgH 2 + Si system …
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Microstructural Engineering of Titanium-Cellulose Nanocrystals Alloys via Mechanical Alloying and Powder Processing
… cost of production. In this thesis, titanium is mechanically alloyed with cellulose nanocrystals followed by powder consolidation and sintering to form a solid titanium metal matrix composite. Cellulose nanocrystals (CNCs) were chosen as the particle reinforcement as they are a widely abundant …
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Structural Characterization and Thermoelectric Performance of ZrNiSn Half-Heusler Compound Synthesized by Mechanical Alloying
… atomic structure were synthesized by mechanical alloying (MA) and consolidation by either Spark Plasma Sintering (SPS) or hot pressing (HP). X-Ray diffraction patterns of as milled powders and consolidated samples were compared and analyzed for phase purity. Thermal conductivity, …
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Production of strengthened copper materials by Mechanical Milling-Mechanical Alloying and Spark Plasma Sintering
… conductivities. In this PhD thesis initially mechanical milling (MM) has been considered as suited strengthening technique due to the severe strain hardening and microstructural refinement induced by severe plastic deformation during the process. Then an enhanced hardening has been obtained by …
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Characterizing the Effects of Mechanical Alloying on Solid State Amorphization of Nanoscaled Multilayered Ni-Ti
Equiatomic composition of Ni and Ti was cryomilled with varying milling times to create Ni-Ti lamella structures with average spacings of 50 nm, 470 nm, and 583 nm in powder particles to vary the interfacial surface area per volume. These surfaces form interfaces for diffusion that are essential …
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Processing of Aluminum Alloys Containing Displacement Reaction Products
Aluminum and metal-oxide powders were mixed using mechanical alloying. Exothermic displacement reactions could be initiated in the powders either by mechanical alloying alone or by heat treating the mechanically alloyed powders. Exponential relationships developed between the initiation time of the …
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Hardness variation and cyclic crystalline-amorphous phase transformation in CuZr alloy during ball milling
… milled specimens, the results shed some light on mechanical alloying theory and favor interpreting mechanical alloying as a driven alloys process.
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Controlling microstructure of nanocrystalline thermoelectrics through powder processing
… their high figure of merit. When processed via mechanical alloying to obtain nanocrystalline structures, their efficiency is increased dramatically, due to enhanced phonon scattering at grain boundaries. However, the excess free energy of these interfaces renders them inherently susceptible to …
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The milling of tin bronze with a Cu-24.6wt%Sn composition
… diffraction. High energy milling has caused mechanical alloying of an elemental copper and tin powder blend, and mechanical milling of a cast powder and a melt quenched powder. Nanocrystalline grains with a size between 5 nm and 50 nm have been directly observed in the final milled powder. …
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An Investigation of the Microstructure and Properties of a Cryogenically Mechanically Alloyed Polycarbonate-Poly(Ether Ether Ketone) System
… relationships of a model cryogenically mechanically alloyed polymer-polymer system: polycarbonate (PC) and poly (ether ether ketone) (PEEK). Mechanically milled and alloyed powders were characterized using a variety of techniques including microscopy and thermal analysis. Cryogenically …
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Microstructure design of mechanically alloyed materials
Nanocrystalline metals have exceptional mechanical properties that make them attractive for structural applications. However, these materials' properties tend to degrade due to grain growth when they are exposed to high temperatures; this makes producing bulk, nanocrystalline components …
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Characterisation of mechanically alloyed feedstock for laser-powder bed fusion: titanium silicon carbide metal matrix composite
… production process involving elements of mechanical alloying, tailored to the requirements of the layer based additive manufacturing (ALM) process. Systematic evaluation and subsequent characterisation of process parameters including laser power, scan speed and hatch spacing are presented. …
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Structural Evolution In Mechanically Alloyed Fe-based Powder Systems
… powders as a function of milling time during mechanical alloying. Blended elemental powders of Fe100-XBX (where x = 5, 10, 17, 20, 22, 25, 37.5 and 50 at. %) and a bulk metallic glass (BMG) composition (Fe60Co8Zr10Mo5W2B15) were subjected to mechanical alloying in a SPEX 8000 mixer mill. X-ray …
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On a Bimodal Distribution of Grain Size in Mechanically Alloyed Bulk Tungsten Heavy Alloys
Elemental W and Ni powders were mechanically alloyed in a SPEX mill with WC grinding media for durations ranging from 5 to 50 hours, then compacted samples were sintered in hydrogen to generate bulk tungsten heavy alloys with 2, 4 and 6 wt.% Ni. Evidence of a bimodal grain size distribution was …
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