Self-Propagating Synthesis of Ti-Al-C Powder Mixtures

2012 ◽  
Vol 520 ◽  
pp. 347-352 ◽  
Author(s):  
Martin Balog ◽  
Roman Florek ◽  
Martin Nosko ◽  
František Šimančík
Keyword(s):  
Powder Mixture ◽  
Exothermic Reaction ◽  
Protective Atmosphere ◽  
Reaction Products ◽  
Simultaneous Formation ◽  
Molten Aluminium ◽  
Master Alloys ◽  
Particulate Reinforced ◽  
Al Matrix

Self-propagating synthesis of Ti-Al-C powder mixture was used for fabrication of master alloys suited to industrial scale manufacturing of Al-TiC composites. The cold compacted powder pellets were heated in a protective atmosphere until the melting point of aluminium. Then the temperature of pellets increased rapidly due to intense exothermic reaction between molten Al and Ti, resulting in simultaneous formation of Al3Ti and Al4C3. When the temperature exceeded ~1090°C, TiC particles started to form as a result of the mutual reaction between Al3Ti and Al4C3. Resulting reaction products consisted of fine (~Subscript textub>2µm) TiC particles uniformly distributed in the Al matrix. The composition of powder mixture was optimized to attain master alloy pellets containing ~50 vol.% TiC. Such pellets were then diluted in molten aluminium to produce Al+TiC composites. In-situ formation of TiC in Al matrix provided favourable interfacial quality, which avoided dewetting and rejection of particles from molten aluminium. The parameters for composite casting were optimized in order to reduce the effect of reversible reaction leading to undesired formation of Al3Ti or Al4C3. The final composites showed significantly increased Young’s modulus and strengths. The potential of using the approach for the fabrication of fine, nearly spherical TiC particulate reinforced Ti composites is briefly discussed. The simple process is very promising for economical manufacturing of highly efficient lightweight structural materials.

Research on Laser Full-Penetration Welding In Situ TiB2 Particulate Reinforced ZL101 Composites

2010 ◽  
Vol 97-101 ◽  
pp. 3967-3973 ◽  
Author(s):  
Hai Chao Cui ◽  
Feng Gui Lu ◽  
Xin Hua Tang ◽  
Shun Yao
Keyword(s):  
High Resolution ◽  
Laser Power ◽  
Particle Distribution ◽  
Welding Process ◽  
Full Penetration ◽  
High Resolution Tem ◽  
Tib2 Particles ◽  
Particulate Reinforced ◽  
Al Matrix

Laser full-penetration welding of novel in situ TiB2 particulate reinforced ZL101 composites was studied using three different welding velocities synchronized with proper laser power. The optimal welding process parameters for laser full-penetration welding of in situ TiB2 reinforced ZL101 composites were suggested. The SEM results show that few pores and uniform particle distribution were obtained. TiB2 particles are intimately contacted with Al matrix according to the results of high-resolution TEM. There was no evidence of chemical reaction at the interface.

Improve Oil Production From Tar-Impacted Reservoirs Using In-Situ Steam Generation and Ionic Liquids

2021 ◽  
Author(s):  
Ayman Al-Nakhli ◽  
Hussain Al-Jeshi ◽  
Olalekan Alade ◽  
Mohamed Mahmoud ◽  
Wajdi Buhaezah
Keyword(s):  
Ionic Liquids ◽  
New Technology ◽  
Exothermic Reaction ◽  
Thermochemical Treatment ◽  
Reaction Products ◽  
Steam Generation ◽  
Sweep Efficiency ◽  
Water Contact ◽  
Steam Flooding

Abstract One of the typical production challenges is occurrence of impermeable layers of highly viscous asphaltenic oil (known as tarmat) at oil/water contact within a reservoir. Tar forms a physical barrier that isolates producing zones from aquifer or water injectors. As a result of tar occurrence, is a rapid pressure decrease that can be observed in such reservoirs, increasing number of dead wells, and declining productivity. Another indirect consequence of Tar presence is poor sweep efficiency that leads to water cut increase by a drastic magnitude. An innovative approach was developed to establish better sweep efficiency, transmissibility and pressure maintenance of Tar impacted-areas using thermochemical treatment. The treatment consists of injecting exothermic reaction-components that react downhole and generate in-situ pressure and heat. The in-situ reaction products provide heat and gas-drive energy to mobilize tar, improve sweep efficiency and maintain flooding for better pressure maintenance. Typically, downhole heat generation through chemical reaction releases substantial heat which could be employed in various thermal stimulation operations. Nano/ionic liquids, high pH solutions, solvents and nano metals were combined with the exothermic reaction to improve tar mobilization. Based on lab testing, the new technology showed more recovery than conventional steam flooding. Permeable channels were created in a tar layer with sandback samples, which enhanced transmissibility, pressure support and sweep efficiency. The effect of thermochemical treatment and ionic liquid on bitumen texture will be described. Impact of In-situ generated heat on injectivity will also be presented. The novel method will enable commercial production from tar-impacted reservoirs, and avoid costly steam flooding systems. The developed novel treatment relates to in-situ steam generation to maximize heat delivery efficiency of steam into the reservoir and to minimize heat losses due to under and/or over burdens. The generated in-situ steam and gas can be applied to recover deep oil reservoirs, which cannot be recovered with traditional steam, miscible gas, nor polymer injection methods.

Preparation and Properties of Halogen Derivatives of Rubber from Latex

1939 ◽  
Vol 12 (3) ◽  
pp. 545-555
Author(s):  
H. C. Baker
Keyword(s):  
Hydrochloric Acid ◽  
Exothermic Reaction ◽  
Oxidizing Agent ◽  
Reaction Products ◽  
Metal Analysis ◽  
Wide Range ◽  
Suitable Amount ◽  
Similar Appearance ◽  
Derivatives Of

Abstract The paper deals with the preparation and properties of chlorine and bromine derivatives of rubber from latex, obtained by the generation of nascent chlorine in situ and by the addition of bromine water. Attention was given to compounds containing small amounts of halogen, which still showed marked elasticity, in addition to the powders containing large proportions of halogen. When stabilized preserved latex was treated with an excess of hydrochloric acid and a suitable amount of oxidizing agent, an exothermic reaction occurred which, if uncontrolled, led to the formation of white powders containing about 50% chlorine which swelled in organic solvents without dissolving. If, however, the temperature was not allowed to rise substantially above atmospheric, at least in the early stages of the reaction, products of similar appearance and chlorine content were obtained, which nevertheless were readily soluble in a wide range of solvents, including vegetable oils, to give thin solutions which formed brittle films adhering strongly to glass and metal. Analysis of a chlorinated rubber containing 55.8% chlorine corresponded approximately to the formula C20H26Cl11O2.

Al2O3/Al particle-reinforced aluminum matrix composite by displacement reaction

1996 ◽  
Vol 11 (6) ◽  
pp. 1562-1569 ◽  
Author(s):  
M. R. Hanabe ◽  
P. B. Aswath
Keyword(s):  
Matrix Composite ◽  
Aluminum Matrix ◽  
Aluminum Matrix Composite ◽  
Displacement Reaction ◽  
Simultaneous Formation ◽  
Multiphase Composites ◽  
Al Matrix Composite ◽  
Al Matrix

The development of a novel Al matrix composite is described based on a simple displacement reaction when an SiO2 particulate preform is brought into contact with liquid Al at temperatures between 1273 and 1373 K. This interaction leads to the wetting of the SiO2 particles by Al and its eventual transformation to a composite with Al2O3/Al particles in an Al matrix. Infiltration of the preform as induced by this reaction takes place with the simultaneous formation of the Al2O3/Al particles in situ. Synthesis of engineered multiphase composites, wherein reinforcements of other materials incorporated into the preform and reacted with liquid Al, is also presented.

scholarly journals Mechanical Properties of Al Matrix Composite Enhanced by In Situ Formed SiC, MgAl2O4, and MgO via Casting Process

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1767
Author(s):  
Yuhong Jiao ◽  
Jianfeng Zhu ◽  
Xuelin Li ◽  
Chunjie Shi ◽  
Bo Lu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Matrix Composite ◽  
Compression Strength ◽  
Casting Process ◽  
Al Alloy ◽  
Pyrolysis Process ◽  
Alloy Matrix ◽  
Al Matrix Composite ◽  
Al Matrix

Al matrix composite, reinforced with the in situ synthesized 3C–SiC, MgAl2O4, and MgO grains, was produced via the casting process using phenolic resin pyrolysis products in flash mode. The contents and microstructure of the composites’ fracture characteristics were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Mechanical properties were tested by universal testing machine. Owing to the strong propulsion formed in turbulent flow in the pyrolysis process, nano-ceramic grains were formed in the resin pyrolysis process and simultaneously were homogeneously scattered in the alloy matrix. Thermodynamic calculation supported that the gas products, as carbon and oxygen sources, had a different chemical activity on in situ growth. In addition, ceramic (3C–SiC, MgAl2O4, and MgO) grains have discrepant contents. Resin pyrolysis in the molten alloy decreased oxide slag but increased pores in the alloy matrix. Tensile strength (142.6 ± 3.5 MPa) had no change due to the cooperative action of increased pores and fine grains; the bending and compression strength was increasing under increased contents of ceramic grains; the maximum bending strength was 378.2 MPa in 1.5% resin-added samples; and the maximum compression strength was 299.4 MPa. Lath-shaped Si was the primary effect factor of mechanical properties. The failure mechanism was controlled by transcrystalline rupture mechanism. We explain that the effects of the ceramic grains formed in the hot process at the condition of the resin exist in mold or other accessory materials. Meanwhile, a novel ceramic-reinforced Al matrix was provided. The organic gas was an excellent source of carbon, nitrogen, and oxygen to in situ ceramic grains in Al alloy.

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