Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 21 for “"powder processing"”.
-
Controlling microstructure of nanocrystalline thermoelectrics through powder processing
… Despite this, little is known about the relevant processing science of these materials with respect to mechanical alloying and powder consolidation. This shortcoming is addressed here via systematic study of the processing-structure relationships that govern these processing operations. Firstly, …
-
Powder Processing and Characterization of W-3Ni-1Fe Tungsten Heavy Alloy
Mechanical alloying, compaction by cold isostatic pressing, and pressureless sintering were used to study the potential for W â 3 wt% Ni â 1 wt% Fe to be processed into the bulk nanocrystalline form as a replacement material for depleted uranium in kinetic energy penetrators. Milling time and …
-
Microstructural Engineering of Titanium-Cellulose Nanocrystals Alloys via Mechanical Alloying and Powder Processing
… 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 and natural material. Additionally, the nanocrystals can be …
-
Effect of Processing Parameters on Bond Strength and Effective Plasticity in Al2O3-TiB2 Composites
… applications. Determining the effect of processing parameters on relative bond strength and effective plasticity may contribute to optimization and predictability of performance in the Al2O3-TiB2 system. Al2O3-TiB2 composites were obtained from a collection of samples that were created …
-
Investigation into the improved dispersion of nickel oxide over the surface of SOFC tubular anodes
… (carbon, graphite, flour) along with alternative processing methods. The porosity forming agent of the SOFC anode was investigated to establish the most effective material to improve nickel dispersion. The effect of powder processing by milling to improve mixing and particle size distribution …
-
Fabrication of ceramic and ceramic composite microcomponents using soft lithography
… using soft lithography and colloidal powder processing. The materials chosen in the research are alumina, yttria stabilised zirconia and their composite for their excellent properties at high temperature.
-
Synthesis and Characterization of Aluminum-Carbon Nanotube Composite by Cryogenic Milling
… Characterization of mechanically alloyed Al-CNT powders was conducted in preparation for bulk powder processing to be used in cold spray. Al-CNT metal matrix composite powders with 5 wt.% and 10 wt.% CNT were synthesized by cryogenic milling of the blended component powders. Stearic acid was used …
-
Numerical and experimental investigation of dry particle coating
… that deal with particulate products and powder processing. Compared to the widely reported experimental studies of the dry particle coating, the theoretical modeling of such processes is found to be less comprehensive. The work presented in this thesis is an attempt to fill this gap. The …
-
Processing, microstructure, and properties of carbon nanotube and silicon carbide composites
… The work was completed to investigate the processing, microstructure, and properties of such materials. Various ceramic engineering techniques aided this investigation including powder processing, sintering, microscopy, spectroscopy, and mechanical testing. These steps were completed in …
-
Solid-state processing of thermoplastic polymers
Although compaction and sintering of polymeric powders has been investigated since the early 1970's, this processing method is not widely used, possibly because the fundamental mechanisms which control compaction and sintering have never been fully understood. This study has made significant …
-
The Effect of Carbon Concentration on the Amorphization and Properties of Mechanically Alloyed Cobalt-Carbon Alloys
… using mechanical alloying, a solid-state powder processing technique. All alloy compositions were milled for up 40 hours. After 20h of milling some of the alloys (≤ 20 at.% C) had partially amorphized, while the higher concentrations had completely amorphized. After 40h of milling, …
-
Sustainable Spacefaring: Exploration of scrap metal powder metallurgy on the lunar surface
… the lunar architectural surface needs for a powder metallurgy processing facility and recommend areas of improvement for the design of future spacecraft to ease the proposed recycling process. While metals can be extracted from the lunar surface, the operation of excavation, separation, …
-
Development of in-situ toughened silicon-rich alloys : a new class of castable engineering ceramics
… more flexible and less expensive than the powder processing routes currently used for engineering ceramics. This thesis will discuss the development of a class of castable silicon-based alloys referred to as silicon-disilicide (Si-XSi2) composites, which naturally form a microstructure …
-
Synthesis, characterization, and properties of carbide dispersion-strengthened tungsten alloys for use as a plasma-facing material in nuclear fusion reactors
… properties. Through the advent of advanced powder processing techniques such as Spark plasma sintering, dense, fine-grained tungsten samples can be developed with these microalloyed microstructures. Spark plasma sintering is a powder compaction technique that provides high pressure and …
-
Physiological characterisation of the neonatal meningitic bacterium Cronobacter sakazakii
… bacterial isolates. The isolates were from powdered infant formula, milk powder factory environments, and milk powder processing equipment; they had not been profiled prior to this study and had previously been identified as E. sakazakii. These environmental strains were obtained from …
-
Discrete element method based scale-up model for material synthesis using ball milling
Mechanical milling is a widely used technique for powder processing in various areas. In this work, a scale-up model for describing this ball milling process is developed. The thesis is a combination of experimental and modeling efforts. Initially, Discrete Element Model (DEM) is used to describe …
-
Effect of dry particle coating on the properties of cohesive pharmaceutical powders
… cohesive active pharmaceutical ingredient (API) powders and their blends. Improving the flow properties of cohesive API powders can significantly improve their handling and subsequent use for pharmaceutical processes such as formulation and manufacturing processing operations. Although it has …
-
Deciphering the role of dispersoids in dispersion-strengthened tungsten alloys on the mechanical properties and irradiation- driven response under nuclear fusion reactor-relevant conditions
… of tungsten. Through the advent of advanced powder processing techniques such as spark plasma sintering, dense, fine-grained tungsten samples can be developed with these microalloyed microstructures. Spark plasma sintering is a powder compaction technique that provides high pressure and …
-
The Effect of Milling Time on the Structure and the Properties of Mechanically Alloyed High Carbon Iron-Carbon Alloys
… were investigated. Mechanical alloying and powder metallurgy methods were used to prepare the samples. Mixtures of elemental powders of iron and 1.4, 3, and 6.67 wt.% pre-milled graphite were milled in a SPEX mill with tungsten milling media for up to 100h. The milled powders were then …
-
Synthesis and Characterization of Wholly Aromatic Semicrystalline Polyimides Based Upon Bis(4-Aminophenoxy) Benzenes
… range of 20-30,000 g/mole. Polyimide powders derived from these ether diamines were prepared by solution imidization at 180°C, to afford about 70% imidized structures as judged by dynamic thermal gravimetric analysis (TGA), before crystallization/precipitation occurred. Relatively …
Page 1 of 2