MATERIALS AND MANUFACTURING PROCESSES

This study is concerned with the influence of the vibration at a specific frequency to the inclined plate during cooling slope casting. A380 aluminum alloy was employed in the present work. The alloy was poured from the inclined plate with an angle of 60 degrees and a length of 500 mm at a pouring temperature of 630 degrees C. The pouring was carried out on an inclined plate with and without vibration. Microstructures of specimens obtained from both conditions were examined. Grain size analysis of specimens was carried out. Experimental results showed that the application of vibration affected the microstructure. Hence, it was determined that the application of vibration increased the nucleation and led to more breaking of dendrite arms. In this study, the convection of melt by vibration played an important role on formation of non-dendritic primary Al-particles

ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING

This paper is concerned with the influence of vibration on the cooling slope casting and gravity casting. Mechanical vibration during cooling slope casting is a new technique. Also isothermal holding period of hypoeutectic Al-Si alloy to prepare semisolid slurry has been studied. The convection caused by the vibration during solidification had remarkable effects on the formation of spherical alpha-Al particles. The main vibration effects include evolution and increase of nucleation and thus reducing as-cast grain size; globularization of particles and production of a more homogenous metal structure. In this work, mechanical mould vibration and mechanical-inclined plate vibration was applied to an AlSi8Cu3Fe alloy at fixed frequency. Metallographic examinations and grain analysis were done on specimens obtained with different pouring temperatures and casting methods. The alpha-Al particles were spherical in cooling slope casting under vibration, as compared with cooling slope casting without vibration and gravity casting with vibration. A grain analysis along with different casting techniques was performed in order to understand the vibration effect. A heat-transfer mechanism seems responsible for the vibration effect in grain formation

Laser peening of metallic materials

Laser peening is a good candidate for the surface treatment industry because of its localized operation, very fast processing, and ability to use multiple types of radiation; therefore, it has recently become a process used for industrial production. The mechanical recoil impulse that arises from rapidly expanding vapor generates high pulse pressure, and the structure of the workpiece changes. In the laser peening process, no melting takes place and a shock wave is generated; compressive residual stresses are induced in the material surface. It is used primarily to increase the fatigue life and improve cracking resistance of engineering materials. Compared with the traditional shot peening process, laser peening creates a higher magnitude of deeper compressive residual stresses in component surfaces, therefore creating high fatigue resistance in metallic materials because these compressive residual stresses inhibit fatigue crack initiation and propagation. Laser peening also has a significant role in improving microstructure, surface morphology, hardness, strength, fatigue life, and corrosion resistance. Laser peening can be applied to a finished surface of a part or before the finishing step, and the process is applicable to a wide range of metals and alloys of titanium, aluminum, nickel, and steels. © 2017 Elsevier Inc. All rights reserved

Investigation of the effects of GW8510 pharmacological inhibitor on in vitro pancreatic cancer model

WOS: 000486972405018[No abstract available

Formation of Globular Microstructure in A380 Aluminum Alloy by Cooling Slope Casting

International Conference on Advances in Materials and Processing Technologies (AMPT) -- OCT 26-29, 2009 -- Kuala Lumpur, MALAYSIAWOS: 000303492800046Thixoforming and related semi-solid processing (SSP) methods require thixotropic materials. One of the many SSP techniques is the cooling slope (CS) casting process, which is simple and has minimal equipment requirements, and which is able to produce feedstock materials for semisolid processing. When the feedstock is reheated to the semisolid temperature range, non-dendritic, spheroidal solid particles in a liquid matrix suitable for thixoforming are obtained. In this study, equipment for the CS technique was first established, and then the effects of the pouring temperature and inclined slope angle on the microstructures of A380 aluminum alloy (ISOAlSi8Cu3Fe) were studied. Optimum parameters for thixoforming experiments were selected, and it was found that the microstructure produced by the inclined plate depended on its angle and the pouring temperature

Performance of Fe-based hardfacings on hot forging die: experimental, numerical and industrial studies

WOS: 000431475200002This paper is an investigation into the use of Fe-based alloys as part of wear resistant hardfacing materials in AISI 1.2714 tool steel. Four different weld hardfacing alloys were deposited on 1.2714 steel substrates using tungsten inert gas welding (TIG) process. Wear tests were carried out using a pin-on-disc wear tester at room temperature. Microhardness and micrographs of the weld overlays were obtained. High-temperature properties were estimated by numerical analysis. The phases of the hardfacings were obtained by XRD and also estimated by numerical analysis. The results from the laboratory tests were then compared with the results obtained from field studies. The results showed that some Fe-based alloys improved dies lifetime; others created poor surfaces. A Fe-based hardfacing alloy D which included high C with Cr, W, Mo had the best wear behavior among the weld overlays.Celal Bayar UniversityCelal Bayar University [2015-110]The authors would like to thank Celal Bayar University (Project Code: 2015-110) for providing financial support. The authors are thankful to EGEMET FORGE Inc. for providing samples and hot forging trials