Wyniki wyszukiwania - BazTech

1

Analysis of Factors Influencing Dry Sliding Wear Behaviour of Laser Remelted Plasma Sprayed Mo Coating Using Response Surface Methodology

Manjunatha S. S., Manjaiah M., Basavarajappa S.

Archives of Metallurgy and Materials

|

2018

|

Vol. 63, iss. 1

217--225

EN

Plasma spraying is a process widely used to fabricate wear resistant coatings. However, various problems are associated with plasma spraying out of which poor bonding strength between the coating and the substrate and the high porosity in the as sprayed coatings are of major concern. In order to eliminate these problems and enhance wear performance, the laser remelting process has been used. The laser remelting of plasma sprayed Mo coatings alters the wear mechanism and improves the wear resistance. The wear mechanism and wear volume loss depend on the applied load, sliding speed and sliding distance. Hence, an effort has been made to investigate the effect of process parameters on volume loss using Response Surface Methodology (RSM) based mathematical models. The experiments were planned as per Central Composite Design (CCD). The investigations revealed that the applied load was the most dominant factor affecting the volume loss of the coating. The sliding speed, sliding distance and interaction effects were considered as the next important parameters influencing the volume loss. The investigation also reveals that, the wear volume loss depends on two wear mechanisms, one being the formations of grooves along surface tribo films and other being fracture of splats with delamination of the coating.

2

Electrical discharge machining of difficult to cut materials

Świercz R., Oniszczuk-Świercz D., Dąbrowski L.

Archive of Mechanical Engineering

|

2018

|

Vol. LXV, nr 4

461--476

EN

The development of industry is determined by the use of modern materials in the production of parts and equipment. In recent years, there has been a significant increase in the use of nickel-based superalloys in the aerospace, energy and space industries. Due to their properties, these alloys belong to the group of materials hard-to-machine with conventional methods. One of the non-conventional manufacturing technologies that allow the machining of geometrically complex parts from nickel-based superalloys is electrical discharge machining. The article presents the results of experimental investigations of the impact of EDM parameters on the surfaces roughness and the material removal rate. Based on the results of empirical research, mathematical models of the EDM process were developed, which allow for the selection of the most favourable processing parameters for the expected values of the surface roughness Sa and the material removal rate.

3

Analysis of the effect of wire electric dischage machining process parameters on the formation of high speed steel form tool

Ishfaq Kashif, Mufti Nadeem Ahmad, Jawad Muhammad, Sajid Muhammad, Jahanzaib Mirza

Advances in Science and Technology. Research Journal

|

2018

|

Vol. 12, no 1

89--98

EN

The use of form tools is growing in industry, owing to their inherent advantage of improving productivity. However, the accurate formation of form tool profile is a really tedious task. In this research work, wire electric discharge machining (WEDM) process has been used for the generation of a form tool. Pulse on-time, pulse off-time, servo voltage, wire tension, flushing pressure have been considered as input parameters, whereas tool geometry (clearance angle, included angle), surface roughness and material removal rate are the selected responses. Response surface methodology (RSM) (Box Bhenken experimental design) technique has been used for design of experiments. Analysis of Variance (ANOVA) has shown that pulse on-time and pulse off-time are the two influential control factors for material removal rate (MRR), surface roughness (Ra), clearance angle and included angle. Contour plot analysis has been performed to find out the optimal ranges of the most influential control factors for each response characteristics.

4

Parametric optimization of rice bran oil extraction using response surface methodology

Ahmad S. W., Javed F., Ahmad S., Akram M., Rehman A.

Polish Journal of Chemical Technology

|

2016

|

Vol. 18, nr 3

103--109

EN

Use of bran oil in various edible and nonedible industries is very common. In this research work, efficient and optimized methodology for the recovery of rice bran oil has been investigated. The present statistical study includes parametric optimization, based on experimental results of rice bran oil extraction. In this study, three solvents, acetone, ethanol and solvent mixture (SM) [acetone: ethanol (1:1 v/v)] were employed in extraction investigations. Response surface methodology (RSM), an optimization technique, was exploited for this purpose. A five level central composite design (CCD) consisting four operating parameter, like temperature, stirring rate, solvent-bran ratio and contact time were examined to optimize rice bran oil extraction. Experimental results showed that oil recovery can be enhanced from 71% to 82% when temperature, solvent-bran ratio, stirring rate and contact time were kept at 55°C, 6:1, 180 rpm and 45 minutes, respectively while fixing the pH of the mixture at 7.1.