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Plastics (polymers) are nowadays clearly a material of choice in all application sectors including in Automobile sector. Automotive manufacturer have relived on new technology for vehicular accessories which are all made-up of different polymers like Acrylonitrile-Butadiene-Styrene (ABS), Poly Carbonates, Poly Methyl Methacrylate (PMMA), Acrylic, glass, resin etc. Although these components offer an impressive range of attractive properties, the effect of climatic conditions on the durability and performance of these materials is not fully understood. The durability, performance and rate of deterioration of these products are all significantly influenced by both the material composition, as well as the climatic conditions to which they are exposed. The degradation/ variation of the mechanical properties of the specimen treated at different environmental/ atmospheric conditions are a primary concern when recommending such a composite for particular use.

Accurate quantification of residual stresses is critical to predict expected fatigue life of the component. Quantification of residual stresses by X ray diffraction method offers substantial accuracy in results as compared to other methods of stress measurements. Depending on component processing and geometry, various stress measurement techniques are used to analyze stress patterns induced by these processing. This paper describes some of the stress measurement techniques by results obtained on two compressor valve (reed) samples which are undergone different processing. First reed sample is analyzed after blanking operation which is expected to give low compressive or tensile stresses whereas second reed sample is analyzed after tumbling operation which is done to get high compressive stresses.

The effect of different cold- rolling and cryo-rolling routes on the strength and ductility of Al-6061 alloy was thoroughly investigated. Rolling decreased the grain size and increased the strength according to the Hall-Petch relationship. However subjecting the samples to ageing at different temperatures and for different time period increased the strength and improved the ductility. The ductility was improved due to the rearrangement and even decrease in dislocation density due to recovery and recrystallization during ageing while the strength was maintained due to ageing. Evolution of microstructure was investigated by optical microscopy, scanning electron microscopy. Preliminary hardness measurements coupled with tensile tests indicate the improvement of both yield strength and ductility. The disparity in ultimate tensile strength, yield strength and the elongation to failure with different ageing temperatures and for different time period is determined and discussed.

Light weighting is significant in for automotive industry as it helps in less fuel consumption and to achieve better performance. Aluminium is a candidate material for light weighting. To design a component made of aluminium material, it is necessary to understand the fatigue performance of the material. In this paper, a study is carried out to understand the fatigue performance of aluminium 6xxx series alloys at an early stage of design without carrying out comprehensive fatigue testing. Coffin Manson Parameters are used to predict fatigue life. This research focusses on determining the gaps in existing models for aluminium alloys by carrying out comprehensive review of various models developed for 6xxx series which uses monotonic tensile data. Two models are developed and the predicted fatigue properties for this class of material are further compared with experimental fatigue, monotonic data and literature.

Dual fuel operating strategy offers great opportunity to reduce emissions like particulate matter and NOx from compression ignition engine and use of clearer fuels like natural gas. Dual-fuel engines have number of potential advantages like fuel flexibility, lower emissions, higher compression ratio, better efficiency and easy conversion of existing diesel engines without major hardware modifications. In view of energy depletion and environmental pollution, dual-fuel technology has caught attention of researchers. It is an ecological and efficient combustion technology. This paper summarizes a review of recent research on dual-fuel technology and future scope of research. Paper also throws light on present limitations and drawbacks of dual-fuel engines and proposed methods to overcome these drawbacks. A parametric study of different engine-operating variables affecting performance of diesel-CNG dual-fuel engines vis-à-vis base diesel operation is also summarized here.

Automobile industry is shifting towards lighter materials in order to meet the high strength to weight ratio as required for better performance, safety, and environmental concern. The objective of this review is to evaluate and compare the different advanced and light weight materials like advanced high strength steel (AHSS), Magnesium and Aluminium alloys, which will help in selection of appropriate materials for their intended application. In this paper comparison of materials on the basis of their current, applications, limitations, cost, potential future applications and percentage wise use in automotive vehicles are discussed. Solutions and suggestions are discussed to overcome the limitations of materials which will widen their future application. Case studies and charts for cost evaluation of different materials, on the basis of structural properties like stiffness and strength are also discussed.

It is an established fact that virtual knowledge based engineering has revolutionized R & D activities by streamlining processes, ensuring productivity and accuracy. This has resulted in freeing up time for quality interpretational work and decision making for engineering the best of products. Subsequently, homologation is a mandatory requisite activity for product signoff. It certifies the quality of the product and is an important factor in giving the product an authenticity for sale in the market. Homologation entails compliance to regulations existing in form of well-established standards which elaborate systematic and detailed guidelines on conducting physical testing for automotive systems, sub-systems or components for specific vehicle types.

In this work, the effect of tool rake angle and cutting speed on residual stresses of tool was studied, the rake angles of 0°, 5°, 10°, 15°, and 20° and a constant clearance (Relief angle) of 8° were used to turn bright mild steel on the lathe machine, A total of 15 experiments were carried out with three different cutting speeds (37.69, 59.37, 94.24 m/min) for each rake angle, keeping the feed rate and depth of cut constant. During the experimentation, the residual stresses were measured using an x-ray diffractiometer. This is all in order to explore the energy savings opportunities during regrinding of tools, useful production time and energy is being wasted due to regrinding or re-sharpening of tools when cutting tools got worn or blunt, selection of the rake angle which generate the optimum residual stresses in the tool, goes a long way in saving these time and energy.

Dual Phase (DP) steels with their high energy absorbing capacity are fast emerging as materials for automotive body applications with improved crashworthiness. The unique combination of high strength and good ductility associated with the DP steels originates from its specially developed microstructure that consists of martensitic islands in ferritic matrix. The high strength and good ductility are expected to give very good resistance to fatigue crack generation and propagation respectively. This paper discusses the fatigue properties determined for a DP steel grade viz. DP 800. The strain controlled fatigue tests were carried out on the un-notched specimens prepared from 1.2 mm sheets to generate E-N curves. The force controlled axial fatigue tests were carried out on two types of specimens prepared from 1.2 mm sheets to generate S-N curves for two Stress Concentration Factors (SCF) viz. 2.5 and 4.4.

In a developing country like India, Two-wheelers dominate the automotive market with around 80% market shares. In Indian city traffic conditions, driving a two wheeler is a tiresome job. Manual transmission makes this task even further uncomfortable. So an automatic transmission is a better solution. A new automatic transmission system is developed which can reduce fatigue of drivers. Steps of ARIZ (Algorithm for Inventive Problem Solving) were followed. Ideas or concepts for the design were proposed from various fields and were compared for various parameters like size, weight, complexity, manufacturability, feasibility, efficiency and cost. They were also compared with the existing transmission systems. Based upon the results of the comparison, 5 designs were selected and they were analyzed thoroughly. Finally one design was selected.

The acoustical performance of a vehicle dash panel system is rated by the noise reduction, which is calculated from the sound transmission and absorption characteristics. A typical dash insulator consists of a steel panel (vehicle body panel), a porous decoupler and heavy layer in the form of sandwich construction. The use of dash panel is to block engine noise from entering into the interior cabin. In the present study the transmission loss of dash panel has been evaluated in reverberation chambers and the sound absorption of dash panel has been determined in impedance tube. This paper deals with improving over all sound transmission loss and shifting of the double wall resonance well below the engine firing frequencies by changing the decoupler materials such as felt and foams of different density and thickness and heavy layer mass per unit area.