Applied Mechanics and Materials Vols. 592-594

Abstract: Ultrasonic horns are tuned components designed to vibrate in a longitudinal mode at ultrasonic frequencies. Reliable performance of such horns is normally associated with the amplitude of vibration, uniformity of vibration amplitude at the working surface and the avoidance of modal participation by non-tuned modes at the operating frequency. In order to maximise vibration amplitude uniformity, standard slotting configurations are included in the horn design. In this work the slot position in the horn is optimised using factorial design of experiments and the mathematical model developed is further interfaced with genetic algorithm. Modal and harmonic analysis of the horn is done using ANSYS software package. It is observed that slotted block horn with optimised slot position vibrates in longitudinal mode with uniform displacement amplitude across the face of the sonotrode.

Abstract: The present paper deals with the comparison and ranking among different rocks (granites) considering sawability as objective parameter. The procedure is based on the combined multiple attribute decision making (MADM) method. The comparison was realised by using combination of TOPSIS and AHP together. Factors such as Uniaxial Compressive Strength, Mohs Hardness, Quartz Content, Abrasiveness, Brazilian Tensile Strength and Grain Size were considered as affecting attributes to sawability of rocks.

Abstract: The rheological behaviour of concentrated coal-water slurries prepared from three different Indian coals were investigated using an Anton Paar rheometer. The perspective was laid in to study the effect of solids concentration on the rheological behaviour of coal water slurry. It was observed that coal water slurry exhibited non-Newtonian pseudoplastic fluid behaviour at concentrations above 30 % by weight. The apparent viscosity varied with the amount of coal in the slurry. The rheological data were utilized to predict the pressure drop characteristics of coal water slurry flowing through a 53 mm diameter slurry pipeline using ANSYS Fluent 14.0 computational fluid dynamics code.

Abstract: For hundreds of year’s composite materials have been playing very crucial role in the field of materials. The applications of composites expanded widely to the aircraft, automotive, sporting goods, and biomedical industries. Today natural fibers like ramie, jowar, sisal, flax, hemp, jute, bamboo, banana, etc. are widely used than the synthetic fibers like glass, carbon, ceramic fibers, etc., because these natural fibres offer several advantages over synthetic fibres. In this project a new natural fiber is introduced to develop Fiber Reinforced Composite. Composite material is fabricated by hand lay-up method by using epoxy resin as the matrix and Hardwickia binata fiber as the reinforcing agent. Mechanical properties such as tensile and impact properties of Hardwickia binata fiber reinforced composites are investigated by varying fiber length and weight fraction. The composite plate is fabricated with different weight fractions of hardwickia binata fiber (5, 10, 15, 20, and 25 wt. %) and different lengths of the fiber (2, 3, 4, 5, and 6 mm). This paper concludes that, the tensile properties increases up to 20 wt. % fiber load with increasing fiber length while the impact properties increases with increasing fiber length and fiber load.

Abstract: An attempt has been made to improve the surface hardness property of mild steel by developing a composite layer on the surface of mild steel using gas tungsten arc as heat source. Silicon Carbide was placed on the surface using a binder and heat was applied using gas tungsten arc. Variation of Silicon content with the weld current parameters was studied. The variation of microhardness with Silicon content on the surface was studied. Optimum parameter for attaining maximum surface hardness property using GTAW (Gas Tungsten Arc Welding) has been found.

Abstract: Burrs are bottleneck of precision machining and automation production. Burrs are formed in every edges and faces, during the turning process, which affects the quality level of surface roughness. In this paper the experimental study of EN3 low carbon steel were carried out to minimize the surface roughness using response surface methodology and genetic algorithm. Tungsten Carbide was used as a cutting tool for this turning operation. Machined samples are examined under Scanning Electron Microscope (SEM) for burr formation. A wide variety of analysis between cutting parameters have been shown graphically. The minimization of burr was achieved and hence better surface quality was obtained by optimizing the cutting parameters like cutting speed, feed, and depth of cut, with the aid of Genetic Algorithm (GA) & Response Surface Methodology (RSM) Techniques.

Abstract: Process planning in a computer integrated manufacturing (CIM) requires integrated system for design and manufacturing activities. For sheet metal part, feature recognition and feature reasoning of a product model for process planning is an essential component of CIM environment. Research work for feature recognition and reasoning has been addressed in literature, which is limited to the geometric and topological information but actual process parameters requited for manufacturing operation is still an open issue. Our research is for extraction of process parameters from a sheet metal part model which is in STEP Format. These process parameters can be used in sheet metal manufacturing to control the operations. This paper presents extraction of process parameters for a sheet metal feature from a sheet metal part model (STEP Format). This work then formulates the feature processes in terms of extracted process parameters, material properties, sheet metal dimension and feature dimension. The actual operation in real manufacturing environment is identified as extension of the proposed work. The extraction of process parameters for sheet metal operation is demonstrated with case studies.

Abstract: Forming processes are defined as to modify the shape of a work piece by deforming it, without the removal of material. To overcome a number of longstanding problems in conventional forming methods such as low production rates, difficulty in forming light weight components etc., an alternate approach of electromagnetic forming process is introduced. Electromagnetic forming (EMF) is a high speed forming process used to form thinwalled work pieces (usually sheets and tubes) that have high electrical conductivity, such as aluminium, copper etc. Electromagnetic tube compression processes, the design of an experimental set up for electromagnetic tube compression process are discussed in detail in this paper

Abstract: The Paper presents the buckling response of composite annular plates with under uniform internal and external radial edge loads using energy method. For the equation of stability Trefftez rule is used. The paper consists of buckling behavior of laminate (90/0) s, influence of some parameters such as thickness, boundary condition, aspect ratio on buckling loads and modes are investigated. Present results are compared with other papers. In this paper the effect of % weight of carbon nanotube (MWCNT) on the buckling load is also investigated.

Abstract: . High thermal conductivity of copper and carbon nano tubes are used in variety of thermal management applications to improve cooling performance. Deposition of copper over these nanotubes increases the hydrophilic wicking surface and increased conductivity and stiffness. The CNT coating and micro patterning are able to provide significant performance enhancements by reducing the surface superheat up to 72% . Conductivity can be increased further by wetting the wicks with conductive fluids. The nanofluids are of great use in this area. Ceramic nanofluid has a very good stability and silver nanofluid has a very good thermal conductivity and hence their mixture is of great use in high temperature applications. Adding of ceramics also ensure the stability of nanofluid suspensions and prevent coagulation. This paper suggests wetting the wicks with ceramic and silver nano fluid mixture in the ratio of 1:5 to increase conductivity and stability for high temperature applications further.