Papers by Keyword: Particulate

Abstract: The economic, performance, and environmental advantages of accepting Aluminium (Al) metal matrix composites (MMCs) over steel, cast iron and light alloys are driving forces behind their utilisation. The transportation industry benefits from reduced noise, reduced emissions from airplanes, and reduced fuel use. Continuous research in this field has resulted in improved manufacturing procedures, allowing these Aluminium based composite materials to be used in aerospace industry, marine and vehicle applications rather than most monolithic materials. The industrial sector is rapidly developing, which increases demand for innovative materials. In cases where 'wear' is a critical issue, conservative materials and alloys have limits in reaching the appropriate hard characteristic. Al-MMCs are composite materials that contain Al or an alloy of Al. It acts as the matrix and the reinforcement distributed across the matrix. Common reinforcing materials include fibres, whiskers, and particles. Because of its enhanced density, great hardness, and thermal stability, ceramic reinforcement is the most used. However, they have limits such as less ability to wet and compatibility with the Al matrix. The major production processes for Al-MMCs are powder and liquid metallurgy. All the manufacturing procedures outlined are appropriate, however casting with stir to mix is cost-effective, particularly for big production runs. The distribution of reinforcement evenly to generate a flaw-free structure at micro level and hence raise the resistance to hard behaviour is a critical difficulty in the synthesis of MMCs of Al. Al-MMCs with particle reinforcement have increased mechanical characteristics and wear resistance. Furthermore, the production of MMCs reinforced with particulates is an exciting task, with questions arising due to ductility decline as the weight percent of ceramic particulate reinforcement is increased, gravity segregation due to denser particulates, and oxidation due to the use of Al alloy, which is very susceptible to oxidation. In the present study Al6061-3% B₄C MMCs have been developed by stir casting technique. Al6061 is an extruded raw material as purchased from the supplier (and not an ingot) used before remelting and manufacturing the MMCs. The microstructure of the manufactured Al-alloy and Al-MMCs are evaluated. It is observed that stir casting is a suitable method to manufacture Al-MMCs.

Abstract: This work has as its objective to evaluate the effect of incorporation of 10 wt% of a powder waste from the sintering stage of an integrated steel-making plant in the physical and mechanical properties of bricks produced in industrial scale. Environmental tests of leaching and solubilization were performed. The results indicated that the waste slightly increased the water absorption of the ceramic and also increased in 35% its compressive strength. The sulfate parameter was above the maximum limit established by the norm for solubilization test. It was observed a strong efflorescence in the massive bricks and a smooth efflorescence in the perforated bricks.

Abstract: In the fields of automobile unto aviation, the extensive applied metal in many optimized output conditions is Aluminium and its based metal matrix composites, which are now-a-days, are called as Aluminium matrix composites (AMCs). These AMCs are as potential as they processed very much able in their mechanical and physical properties viz., tensile strength, strain, hardness, wear and fatigue. In this review, the properties which are essentially vital in attaining such improved performance in particular applications are discussed along with the special methodologies and their limitations in brief. Hence, the effective factors which are the cause for their output, like, type of reinforcement, amount of reinforcement, size of particulate of reinforcement, temperature and pressure etc., were also scrutinized retrospectively.

Abstract: The microstructures of particulates fueled with ethanol/diesel, DMC/diesel, and biodiesel/diesel blends were studied using the scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The effects of oxygenated fuels on the microstructures of particulates were studied. The results showed that the particulates presented with chain and group like structures. The particulate size was approximately following the normal distribution. With the increase of oxygenated fuels blends ratios, the extent of agglomeration increased and the structure arrangement became closer.

Abstract: In order to reduce effectively the particulate ignition temperature of Diesel Particulate Filter containing MnO_x-CeO₂ catalysts，the physical and mathematical calculation models of MnOx-CeO₂ catalysts were established on Diesel Particulate Filter，and according to bench tests, the activity measurements of the five different concentrations were processed for MnOx-CeO₂ catalyst. The results indicated that when concentration is 20ppm, the ignition temperature can be droped about 105°C, activity measurements of Kp、Kpm and ΔKp decrease 10%, 8% and 7% respectively. Meanwhile, regeneration time can be shortened to 7min. It shows that Diesel Particulate Filter which contains concentration of this type not only has higher regeneration rate and level , but also decrease effectively exhaust back pressure.

Abstract: A study on low-cycle and high-cycle fatigue behaviour of 6061-Al₂O₃ composites reinforced with nominal volume fractions of 10% and 20% of Al₂O₃ particulates is presented. The effects of reinforcement geometrical features (volume fraction and size) and of the loading mode experienced during the different kind of fatigue tests (strain controlled and stress controlled tests) were evaluated. A relation with crack growth mechanisms was drawn by analyses on fracture surfaces and on longitudinal sections of specimens subjected to the fatigue tests. The micromechanisms of cyclic deformation and of microstructural damage acting in the materials are discussed and compared to data and observations available from the wide published literature.

Abstract: In these years, glass industry has several problems to solve which are derived from environmental protection, energy saving, resource saving, demands for high quality glass and so on. Refractory for the glass melting also has some problems corresponding to the glass industry, such as more corrosive service circumstance, less glass contamination from the refractory, recycling and so on. NOx reduction, one of the environmental protection, brings the oxy-fuel combustion and/or the reducing atmosphere operation of glass melting into the glass industry. Under the reducing atmosphere, some kind of refractories can not endure for a long period of time and under the oxy-fuel combustion, refractories ought to endure around 3 to 4 times more severely corrosive circumstance. Thus, the problems of refractory that are corresponding to the glass industry are explained and discussed in this presentation. The solutions for the above are also discussed and presented, if possible in the presentation.

Abstract: The tensile behaviour of nanometric SiC particulate (SiCp) reinforced aluminium matrix composites (AMCs) was examined at room temperature, 215°C and 350°C. These AMCs were produced via powder metallurgy (P/M) using Al 7075 powder reinforced with different volume fractions (1 vol.%, 3 vol.% and 5 vol.%) of nano-SiCp. The experimental results exhibit that at room temperature un-reinforced Al has both maximum strength and ductility whereas the 5 vol.% SiCp/Al composite has only maximum stiffness. Similar trends were obtained for tests performed at 215°C. However at 350°C, the 1 vol.% SiCp/Al composite has the highest stiffness. Optical microscopy and scanning electron microscopy were performed for microstructure study, examination of the SiCp distribution in the Al matrix and fractography.