Applied Mechanics and Materials Vol. 895

Abstract: Wire electric discharge machine (WEDM) is a non-conventional machining process used to machine the hard to cut materials. WEDM has wide applications in die and punch industries, automobile, aerospace and medical industries. In this process the material is processed with the help of a wire electrode. In present work, Al6063/SiC/Ti composite was processed with the help of WEDM. As this spark-erosion machine tool have number of input process parameters, so to process any material it became mandatory to investigate the range of the machining parameters in which machine tool operate successfully. Every material represents its unique material characteristics due to which it can be machined successfully in a limited range of the parameters. Above and below this range the wire will break abruptly. So, in this present work an attempt has been made to investigate the range of the process parameters in which WEDM can process Al6063/SiC/Ti composite efficiently. The input parameters considered for the present work are pulse on-time, pulse off-time, servo voltage, peak current, wire feed and wire tension. After the experiments it was found that the pulse on-time, pulse off-time, servo voltage and wire-feed were the significant process parameters in the investigations of cutting rate and surface roughness.

Abstract: In this research work an effort has been made to study the tensile behavior of boron carbide and copper coated short basalt fiber reinforced with Al2014 based hybrid composites are prepared by stir casting technique. To avoid the interfacial reactions between basalt fiber and matrix Al2014 alloy the fibers are coated with copper using copper sulphate solution by electroless deposition method.The coated fiber was observed by scanning electron microscopy (SEM). It has been clearly revealed the uniform deposition of copper on the surface of fiber and tensile behavior of Hybrid composites was increased with increase in the wt% of reinforcements. At 6% boron carbide and 8% copper coated basalt fiber shows maximum tensile property.

Abstract: In this paper, experiments are conducted on drilling AISI 316L Austenitic Stainless Steel material using minimum quantity lubrication technique under formulated environmental friendly Pongam oil as cutting fluid. Cutting torque, Thrust force and Surface roughness and Chip formation are studied for the evaluation. The experimental results show that, the Cutting torque is dropped by 36 % under modified Pongam oil as cutting oil, compared to mineral oil base cutting fluid. About 34 % drop in Thrust force and Surface roughness values are noticed under formulated Pongam oil. Further, spiral and continuous form chips are seen under vegetable oil mode of lubrication compared discontinues spiral form under mineral oil based cutting fluid.

Abstract: This paper presents the effect of zirconia filler on mechanical properties and dry sliding wear of bidirectional hybrid (glass and basalt fiber) fabric reinforced epoxy (G-B/E) composites. Fabrication was done by hand layup method followed by compression molding. The effect of zirconia filler loading on mechanical characteristics like hardness, tensile and flexure of fabricated G-B/E composites were determined according to ASTM standards. Also, wear behavior under dry sliding condition was performed using pin-on-disc machine for different applied normal loads/sliding distance. Experimental results reveal that incorporation of zirconia filler improves the mechanical properties. Further, the wear test results indicated addition of zirconia into G-B/E hybrid fiber composites plays important role on specific wear rate under the tribo-conditions selected for the study. Further, inclusion of zirconia into G-B/E composites shows improved wear resistance and addition of 6 wt. % of zirconia exhibits least specific wear rate compared to other hybrid G-B/E composites. In addition, Scanning electron microscope images of selected mechanical test fractured coupons also have been discussed.

Abstract: Most machining processes produce burr as a result of plastic deformation. Exit burr strongly affect product quality during assembly and it is difficult to remove them easily. This work aims at minimizing burr produced in drilling of Al6061/SiCp composite fabricated through stir-casting process using HSCO drill. Analysis of experimental results using ANOVA indicated the influence of cutting conditions and drill geometry in reducing the thrust force as well as burr size. Keywords: Drilling, Al6061/SiCp, HSCO drill, ANOVA, Thrust force, Burr

Abstract: Lubricants have a very crucial role in machinery industry for friction reduction and wear reduction between two relatively moving parts. The current study enlightens the works from various authors on evaluating the tribological behavior of environment friendly vegetable based oils as emerging biodegradable lubricants. The influences of the vegetable oils on friction and wear performance using different Tribometers were reported. The review focuses efforts on the development and commercialization of these vegetable based oils as industrial lubricants for manufacturing industries, mainly, metal forming and metal cutting. The review reveals that, many vegetable oils can be used as industrial lubricant, due to their exemplary attributes in terms of friction and wear reduction, which would help to decrease the universal demand of commercial lubricants which are based on petroleum resources to a great extent.

Abstract: This paper is concerned with the preparation and characterization of transformer oil based nanofluids with the suspensions of Al₂O₃ and CuO nanoparticles . As a part of experimental study the transformer oil based nanofluids for heat exchangers in transformer cooling application, preparation and characterization has been performed. The preparation of nanofluids is the first key step in experimental studies with nanofluids. One step technique and two step technique are generally used for preparing the nanofluids. This work deals with the preparation methods of (Al₂O₃-Transformer oil ,CuO-Transformer oil) and characterizing the transformer oil based nanofluids of different volume concentrations (0.05%, 0.1%, 0. 5%, 1.0% and 1.5%).From the results it is revealed that increasing the volume concentration resulted in increase in thermal conductivity, viscosity of the nanofluid and decrease in density and specific heat of nanofluid.

Abstract: The present work is aimed to experimentally determine the mechanical properties such as Rockwell Hardness Number (RHN), tensile strength and two parameters of Weibull distribution curve (i.e. Weibull shape and characteristic life parameters) of fatigue life for the Poly Tetra Fluoro Ethylene (PTFE) material. The ultimate stress of PTFE specimen is determined using tensometer and its shape parameter and characteristic life are determined from rotary test bending machine. The PTFE specimen is also tested for wear and friction performance on pin-on-disc test rig. Based on the hardness test, RHN of PTFE was found to be 57 and its ultimate engineering stress was observed to be 20.5N/mm². The Weibull shape parameter and characteristic life of PTFE specimen were observed to be 13.33 and 6734.5 cycles respectively. From the wear test result the sliding speed was found to have maximum influence on wear volume followed by sliding distance where as the load has least influence. .

Abstract: This work deals with the design of fringe capacitance based non-contact type liquid level sensor employing self-compensation feature. The existing capacitive type sensors require additional compensation to overcome the problem of various stray capacitances, specifically due to atmospheric corrosion. This paper emphasizes on the selection of suitable material to accomplish the self-compensation feature in corrosive environment. Rate of attack of corrosion is studied on Copper (Cu) and Aluminium (Al) samples under drizzling environment. Visual Analysis of SEM images of samples exposed for different durations reveal that Al protects itself from the corrosion. Further, performance evaluation of two sensor units with Cu and Al electrodes under the same drizzling environment beside the respective samples indicate that sensor with Al electrodes facilitates the feature of self-compensation in corrosive environment. Further, the sensor is interfaced with Siemens PLC-S200 for liquid threshold level monitoring.

Abstract: To tackle one of the major environmental issues concerning modern day mankind, that is air pollution and to reduce dependency on other countries for conventional fuel, finding an alternative fuel is of high priority. Biodiesel is one such alternative. Adding nanoparticles like Carbon nanotubes (CNT) leads to reduction in emissions and enhancement in performance. In this context, in the present paper an experimental investigation was carried out on a computerized single cylinder water cooled diesel engine coupled with an eddy current dynamometer to determine the impact of blending CNT with biodiesel (Neem Oil Methyl Ester or NOME) and a comparative study of various blends using diesel as the baseline was done. The concentration of CNT used were 25 ppm, 50 ppm and 100 ppm CNT blended with B20 biodiesel. The blends were prepared using homogeniser. Readings were recorded for different loads for all the blends and comparative graphs were drawn for performance, combustion and emission characteristics. There was an improvement in the performance characteristics with 8.1% increase in BTE, lowered emissions with 0.0785% decrease in CO and 8.15% decrease in UBHC emissions along with improved combustion relative to diesel when CNT (50 ppm) was added to B20 biodiesel.