Deformation–wear transition map of DLC coating under cyclic impactloading

A new deformation–wear transition map of hydrogen-free amorphous carbon coating(commonly known as Diamond-Like Carbon(DLC)coating)on tungsten high speed steel(SKH2)substrate under cyclic impact loading has been proposed to clarify the interactions of the operating parameters,deformation and wear. The study was carried out using an impact tester,under lubricated conditions over a wide range of impact cycles, and applied normal loads. SKH2 discs were coated with thin DLC films using a Physical Vapor Deposition (PVD) method. Tungsten (W) was used as an interlayer material. The DLC coated disc was impacted repeatedly by a chromium molybdenum steel(SCM420) pin. All impacttests were conducted at room temperature. It has been suggested that the deformation–wear transition map is an easy way to illustrate the impact wear mechanisms of DLC coating, as shown by its transition zones. Initially,the DLC coating only follows the plastic deformation of the substrate until several impact cycles. Then, a suppression of plastic deformation of the substrate is taking place due to the decreasing contact pressure with impact cycles to the yield point.Wear ofthe DLC coating becomes dominant when the critical limit of maximum normal impactload and impact cycles is exceeded. From experimental observations, some degradation ofthe DLC coating occurs within the wear zone

Tribology in Malaysia: General perspective

Tribology was first coined in 1966 as documented in ‘Jost Report’. The word ‘tribology’ has since gained a common usage for matters related to friction, wear, and lubrication in machine in-teractions. Since tribology is an engineering issue that goes beyond national boundaries, many tribology societies have emerged across the continents partly motivated by the pursuit for green-er world via waste reduction. The move for improved tribology practices in industry has reached Malaysia and in 2007, Malaysian Tribology Society (MYTRIBOS) was established by local tribol-ogists [1]. MYTRIBOS is responsible to promote proper practices in research and development related to the field of tribology in Malaysia and to facilitate collaborations between academia and industry in all possible endeavors. MYTRIBOS eventual vision and mission is to help reduce en-ergy consumption by making machineries more energy efficient in order to reduce greenhouse gas emission. MYTRIBOS is contributing towards the improvement of the environment and to achieve a better quality of life and more sustainable world by creating awareness of the impor-tance of practicing proper tribology

Preliminary Design of Side Door Impact Beam for Passenger Cars using Aluminium Alloy

The growing demand for more fuel efficient vehicles to reduce energy consumption and air pollution provides a challenge for the automotive industry. The best way to increase fuel efficiency, without sacrificing safety, is to employ aluminium alloy within the body of cars, due to its higher strength to weight ratio than that of conventional steel. In this study, during the early design stage, structural modifications were studied using Finite Element Analysis (FEA), to determine a suitable cross-section shape for the side-door impact beam. The impact energy absorption characteristics of aluminium alloy and high-strength steel were investigated using a Charpy impact test. The fracture and surface contour of both materials were observed after impact testing. The preliminary results showed that a square hollow cross-section type was suitable for side-door impact beam use, due to its yield at the highest bending load. Both materials exhibited differential fractures and surface contours after impact testing, which directly indicates that aluminium alloy experienced a ductile fracture and had higher impact energy absorption than the high-strength steel

Preliminary Design of Side Door Impact Beam for Passenger Cars using Aluminium Alloy

The growing demand for more fuel efficient vehicles to reduce energy consumption and air pollution provides a challenge for the automotive industry. The best way to increase fuel efficiency, without sacrificing safety, is to employ aluminium alloy within the body of cars, due to its higher strength to weight ratio than that of conventional steel. In this study, during the early design stage, structural modifications were studied using Finite Element Analysis (FEA), to determine a suitable cross-section shape for the side-door impact beam. The impact energy absorption characteristics of aluminium alloy and high-strength steel were investigated using a Charpy impact test. The fracture and surface contour of both materials were observed after impact testing. The preliminary results showed that a square hollow cross-section type was suitable for side-door impact beam use, due to its yield at the highest bending load. Both materials exhibited differential fractures and surface contours after impact testing, which directly indicates that aluminium alloy experienced a ductile fracture and had higher impact energy absorption than the high-strength steel

Phase transformation studies on the a-C coating under repetitive impacts

The phase transformation of hydrogen-free amorphous carbon (a-C) coating on tungsten high speed steel (SKH2) substrates under repetitive impact testing has been studied. The a-C coated disc was impacted by the chromium molybdenum steel (SCM420) pin at several different impact loads and impact cycles (up to 100,000) under lubricated conditions. The results show that the sp3 fractions of impacted a-C coating obtained from the surface of impact craters are significantly increased with impact cycles due to decreasing ID/IG ratio. This means that the amorphization of a-C coating also increased after several impact cycles. As for the full-width at half maximum (FWHM) of G peak characterization, it is shown that the hardness of impacted a-C coating is higher than the as-received. From the observation of surface roughness using atomic force microscopy (AFM), it is supposed that increasing sp3 fractions and the hardness of the impacted a-C coating during impact correlate to the reduction of surface roughness. In addition, the tribochemical reaction to the environment during impact occurred at the mating material, where the transfer layer adhered, as well as in the wear debris. This is due to the oxidation of ferrum (Fe) to magnetite (Fe3 O4) and hematite (α-Fe2 O3) phases with predominant peak at about 680 cm−1 and 1317 cm−1 , respectively. The formation of Fe3 O4 and α-Fe2 O3 phases was revealed from Raman spectroscopy and the existence of oxide elements was verified by energy dispersive X-ray spectroscopic (EDS) analysis. Increasing the G peak position, together with a concomitant decrease of their width, it is believed that the structural transformation from sp3 to sp2 is taking place within the wear debris and leads to the graphitization process at a higher contact pressure. It was suggested that the high contact pressure is not just only corresponding to the applied normal impact load, but it is also exerted by an oil lubricant during impact. A high contact pressure can significantly reduce the graphitization temperature and substantially accelerate the graphitization process. However, a significant phase transformation of the transfer layer on the SCM420 pin does not intensely occur because it is mainly coming from the surface layer of the impacted aC coating, where the sp3 content increases and no wear debris is observed inside it

Proposal for hybrid passive cooling system of batteries In the electric car

This paper addresses the challenges faced by Electric Vehicle (EV) thermal management system and proposed a method to overcome them. Due to the non existence of internal combustion engine (ICE) in EV, the driving mechanisms of conventional cooling system need to be revamped. Therefore, in this paper a combination of liquid cooled, air cooled and phase change material (PCM) cooling system was introduced. The main heat dissipation from EV was identified coming from electric motor, battery module and the electronics controller and components. As this is a preliminary study, the reliability and sustainability of the system need to be further investigated. The investigation would include the, simulation and modeling of heat dissipated from the EV and also the cooling capacity of the proposed cooling system

Effect of Vaned Diffuser on the Performance of Small Turbocharger

This work presents an experimental investigation of performance of small turbocharger compressor with vaned diffuser. The aim of the study is to investigate the effect of number vaned diffuser on peak pressure ratio in turbocharger. The study was carried out using cold-flow turbocharger test rig driven by compressed air with the impeller rotational speed from 40,000 to 70,000 rpm. Tests were conducted with 6, 8 and 10 number of vanes while maintaining the vane blades angle of 6°, turning angle of 30° and blade length of 21.8 mm. The vanes as a flow deflector were designed as a thin flat plate of 1 mm thickness. All the results were compared with original vaneless diffuser of the compressor. The results found that the proposed design of 6 and 8 vanes shifted the peak pressure ratio toward low mass flow rate region. It was observed that modification from conventional vaneless diffuser compressor to the one equipped with vaned diffuser has significant improvement on the overall pressure ratio of the turbocharger

When should i change my tire?

Tires are one of the most fundamental parts on your car. Tires not properly inflated and well maintained will wear prematurely, waste of fuel and can caused a collision. According to survey, tire is the most neglected item of automotive maintenance. In certain situations, a tire can be repaired. However, the repair of tires must be preceded by a careful examination of all areas of the tire, inside and out, by a trained specialist. The removal of the tire from the wheel is essential because internal damage is not visible while the tire is fitted. Motorists are advised to regularly check the state of tires from any signs of noticeable damage or abnormal wear. Below, seven major reasons when you should seriously consider changing your tires (refer Figure 1): a. The tread is down to 1.6 mm of the tread wear indicator. b. Signs of uneven wear, cracks and lump on the tire tread/wall. c. Punctured more than 5 times on the same tread area or punctured hole. d. Puncture in the tire side wall or lower shoulder. e. Damage to the tire wall. f. Uneven tire tread due to the long time parking. g. Tire has been used more than 5 years. Retread tires are growing in popularity due to their cost efficiency, environmental friendliness, and quality performance. Retread, also known as "recap," or a "remold" is a re-manufacturing process for tires that replace the tread on worn tires. Retreading is applied to the spent tires casings that have been inspected and repaired.[1]. It preserves about 90% of the material in spent tires and the material cost is about 20% less than manufacturing a new one. According to Deputy Minister of Transport, Malaysia, YB Datuk Ab. Aziz Kaprawi, retread tire is safe to use as it complies with the Malaysian Standard (MS) 224 (Specification for Retreading of Pneumatic Rubber Tires for Passenger Car and Commercial Vehicle) in addition to United Nations R108 (Retreaded Pneumatic Tires) and R109 (Retreaded Pneumatic Tires for Commercial Vehicles). Besides, statistics of road accident released by Royal Malaysian Police shows that only 8 of 30,458 road accident cases in 2013 involving problem of retreading [2]

The application of calcium oxide from waste cockle for biodiesel production from used cooking oil via microwave heating system

An experimental investigation was conducted to explore the heterogeneous catalytic performance of activated waste cockles derived CaO on the biodiesel production of used cooking oil via microwave heating system. The catalyst was characterized by Xray diffraction (XRD), scanning electron microscope (SEM) and X-ray fluorescence (XRF) method. The effects of reaction parameters such as reaction time, methanol to oil molar ratio, catalyst concentration, and microwave exit power on the yield of biodiesel were investigated. It is clearly observed that the catalyst activity still sustained up to three successive cycles. The fuel properties of the biodiesel produced were compared with the ASTM D6751 and were in accordance with the standard method. More than 95% yield concentration was recorded through the microwave irradiation method which shows that it can be employed as an energy source due to its ability in accelerating the transesterification process

Proceeding Of Mechanical Engineering Research Day 2016 (MERD’16)

This Open Access e-Proceeding contains a compilation of 105 selected papers from the Mechanical Engineering Research Day 2016 (MERD’16) event, which is held in Kampus Teknologi, Universiti Teknikal Malaysia Melaka (UTeM) - Melaka, Malaysia, on 31 March 2016. The theme chosen for this event is ‘IDEA. INSPIRE. INNOVATE’. It was gratifying to all of us when the response for MERD’16 is overwhelming as the technical committees received more than 200 submissions from various areas of mechanical engineering. After a peer-review process, the editors have accepted 105 papers for the e-proceeding that cover 7 main themes. This open access e-Proceeding can be viewed or downloaded at www3.utem.edu.my/care/proceedings. We hope that these proceeding will serve as a valuable reference for researchers. With the large number of submissions from the researchers in other faculties, the event has achieved its main objective which is to bring together educators, researchers and practitioners to share their findings and perhaps sustaining the research culture in the university. The topics of MERD’16 are based on a combination of fundamental researches, advanced research methodologies and application technologies. As the editor-in-chief, we would like to express our gratitude to the editorial board and fellow review members for their tireless effort in compiling and reviewing the selected papers for this proceeding. We would also like to extend our great appreciation to the members of the Publication Committee and Secretariat for their excellent cooperation in preparing the proceeding of MERD’16