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Copper is almost inevitable functional filler in the brake-material and efforts to replace it are continuing since it is now known as a hazard to the aquatic life. It is always desirable to search for ingredients for Cu-free brake-pads, which will be beneficial for friction-related properties and especially fade resistance. Attapulgite, is a mineral which was proven to be an excellent substitute for asbestos in brake-pads long back. However, hardly anything in details is reported on its exact role in controlling tribo-properties of friction materials (FMs). It was of interest, if it can be helpful in enhancing the performance of Cu-free FMs. Hence, in this work a series of brake-pads (five types) was formulated and developed with increasing amount of attapulgite (0, 5, 10 and 15 wt. %) by compensating with inert barite particles in Cu-free FMs. The parent composition was fixed and instead of Cu powder, 10 wt.% stainless steel powder was used.

Metallic particles in brake-friction materials (FMs) play a vital role in improving mainly strength, friction level, thermal conductivity and hence resistance to fade during braking operations. Although Copper was the most efficient and popular metallic ingredient in FMs, it is being phased out because of its proven threat to the aquatic life in the form of wear debris. Hardly any successful efforts are reported in open literature barring few on in the authors’ laboratory. It is well-known that the size and shape of particles affect the performance of composites apart from their type, concentration, etc. In this paper, Ferritic stainless steel (SS 434) particles were selected as a theme ingredient in two forms, first particulate (SSP) with two sizes, larger (30-45 micron) and smaller (10-20 micron) and also in the form of swarf. The aim was to investigate the size and shape effect of these ingredients when used to manufacture the brake-pads on the performance properties.

Graphite plays a crucial role in friction materials, since it has good thermal conductivity, lubricity and act as a friction modifier. The right type, amount, shape, and size of the particles control the performance of the brake-pads. The theme of the study was investigating the influence of size of graphite particles (having all other specifications identical) on performance properties of brake-pads containing graphite particles in the average size of 60 μm, 120 μm, 200 μm and 400 μm. Physical, mechanical and chemical characterization of the developed brake-pads was done. The tribological performance was studied using a full- scale inertia brake dynamometer following a Japanese automobile testing standard (JASO C406). Tribo-performance in terms of fade resistance, friction stability and wear resistance were observed best for smaller graphite particles. It was concluded that smaller size serves best for achieving best performance properties barring compressibility.

Non-Asbestos Organic (NAO) brake- material research has been significant in the last decade in an attempt to replace the conventional semi-metallic and asbestos based materials. Influence of ingredients in this multi-ingredient (generally 10-25 in different proportions) system on performance properties, however, is still not thoroughly researched area because of complexity involved and needs intensive efforts to understand this aspect. Graphite is one of the most important and almost inevitable ingredients in friction materials. A wide variety of graphite varying in origin, particle size, crystallinity, thermal conductivity etc. is used by the industry. An in-depth and systematic study on the influence of size of graphite on tribo-performance, however, is not available.

Phenolics or their modified versions are invariably used as binder materials for friction composites which consist of multiple ingredients. However, phenolics are known for their inherent serious problems such as; poor shelf life, which poses constraints for storage and transportation; evolution of harmful volatiles leading to voids, cracks and environmental pollution etc. In order to overcome these, three new thermoset able resins having oxazine ring were synthesized in the laboratory. These resins proved to be free from the above mentioned drawbacks. These were tribo-evaluated to explore the possibility of replacing currently used phenolics in friction materials. In order to evaluate their tribo-potential as friction materials, friction formulations (non-asbestos organic NAO) based on these resins were developed in the laboratory in the form of brake-pads and tensile specimens.

Fatigue design has to account for the scatter of component geometry, material behavior and loading. Scatter of the first two variables is mainly due to manufacturing and material sourcing. Loading on the other hand depends decisively on operating conditions and customer usage. Loading is certainly most difficult to determine. Tests on proving ground or even long-term real time measurements are used to obtain actual load time histories. Because of the costs of measurements and safety measure, real-time measurements are used exceptionally to gain changes in the usage profile. In this paper, an attempt has been made to find the difference in the extrapolated data to the actual data. A comparison has been made between the actual road distance of 2000 km to the extrapolated data of 100 km, 500 km and 1000 km to 2000 km. The front Axle channel is taken for the study.

In a significant number of automobile crashes involving pedestrians, the ligaments which control the stability of the knee, often get severely loaded. In lateral impact on knee during automotive crashes, varus-valgus motion results in failure of ligament by avulsion or by rupture in the middle region It is known that properties vary in different regions of the ligament. Experimental measurement of tensile load-elongation behavior of the middle region of bovine medial collateral ligament at strain rates of 10−4 /s to 160/s are reported here. The results show that the stress-strain behavior is linear under quasi-static loading whereas it is nonlinear and strain rate sensitive in dynamic loading conditions.

A single cylinder, direct injection diesel engine was run on water diesel emulsion at a constant speed of 1500 rpm under variable load conditions. Water to diesel ratio of 0.4 on the mass basis was used. Tests indicated a considerable reduction in smoke and NO levels. This was accompanied by an increase in brake thermal efficiency at high outputs. HC & CO levels, ignition delay and rate of pressure rise went up. The heat release rate in the premixed burn period was higher. When the oxygen concentration in the intake air was enhanced in steps up to 25% along with the use of water diesel emulsion, the brake thermal efficiency was improved and there was a further reduction in the smoke level. HC and CO levels also dropped. NO emission went up due to increased temperature and oxygen availability. An oxygen concentration of 24% by volume was optimal as the NO levels were near about base diesel values.

Performance of a Current generation catalytic converter using Pd/Rh (10:1) as binary catalyst impeded on an ultra thin ceramic substrate and alumina wash coat is modeled for performance prediction and parametric optimization. Kinetic rates for the catalyst are reduced after conducting series of experiments on a passenger car engine. A new concept in mass transfer coefficient is introduced for improving accuracy of the model prediction. In order to take care of the precious metal resources and to become independent of precious metal price fluctuation, a new pattern of loading of precious metal is suggested for optimum performance and metal savings about 46 percent was observed. Experimental investigations were carried out to validate the established kinetic rates over a wide range operation of the engine and for the model validation. Satisfactory agreements are observed for the model prediction and experimental results.

Minimum weight and high-efficiency gearboxes with the maximum service life are the prime necessity of today’s high-performance power transmission systems such as automotive and aerospace. Therefore, the problem to optimize the gearboxes is subjected to a considerable amount of interest. To accomplish these objectives, in this paper, two generalized objective functions for two stage spur-gearbox are formulated; first objective function aims to minimize the volume of gearbox material, while the second aims to maximize the power transmitted by the gearbox. For the optimization purpose, regular mechanical and critical tribological constraints (scuffing and wear) are considered. These objective functions are optimized to obtain a Pareto front for the two-stage gearbox using a specially formulated discrete version of non-dominated sorting genetic algorithm (NSGA-II) code written MATLAB. Two cases are considered, in the first with the regular mechanical constraints.

The mechanical and wear behaviour of an alloyed gray cast iron with ausferrite microstructure directly obtained on solidification has been compared with austempered alloyed gray iron. As-cast ausferritic gray iron shows finer ausferrite and graphite flake morphology compared to austempered alloy. The volume of retained austenite is about 30% higher in as-cast ausferritic iron due to higher amount of alloying additions. The mechanical and wear properties of as-cast ausferritic iron are almost similar to austempered alloy.

Copper ion-exchanged X-zeolite with urea infusion was tested for nitrogen oxide (NOx)conversion efficiency in this study. Temperature datapoints were obtained to arrive at peak activation temperatures. Variation of the air/fuel ratio showed the widening of the λ-window(the range of air-fuel ratios over which the NOx conversion efficiency is considerable); a maximum of 62% NOx conversion efficiency was obtained in the lean-burn range. Effects of space velocity variations were also observed. In order to minimise the deactivation of zeolite caused by water, ammonium carbonate and ammonium sulphate were deposited on the copper ion-exchanged X-zeolite and the corresponding NOx conversion efficiencies measured. Ammonia slip (leakage of unreacted ammonia), a prospective pollution hazard, was observed to be more in case of urea infusion than ammonium salt deposition at higher temperatures.

Three catalysts based on X-zeolite have been developed by exchanging its Na+ ion with Copper, Nickel and Vanadium metal ions and tested in a stationary SI engine exhaust to observe their potentialities for NOx and CO controlling. The catalyst Cu-X, in comparison to Ni-X and V-X, exhibits much better NOx and CO reduction performance at any temperature. Maximum NOx conversion efficiencies achieved with Cu-X, Ni-X and V-X are 62.2%, 59.7% and 56.1% respectively. Unlike noble metals, the doped X-zeolite catalysts, studied here, maintain their peak NOx reduction performance through a wider range of A/F ratio. Back pressure developed across the catalyst bed is found to be well within the acceptable limits.

In this work methanol was port injected while diesel was injected using a common rail system in a single cylinder non-road CI engine. Experiments were conducted with single (SPI) and double (DPI - pilot and main) injection of the directly injected diesel at 75% load and at a constant speed of 1500 rpm. The effects of methanol to diesel energy share (MDES) and injection scheduling on combustion stability, efficiency and emissions were evaluated. Initially, in the SPI mode, the methanol to diesel Energy Share (MDES) was varied, while the injection timing of diesel was always fixed for best brake thermal efficiency (BTE). Increase in the MDES resulted in a reduction in NOx and smoke emissions because of the high latent heat of vaporization of methanol and the oxygen available. Enhanced premixed combustion led to a raise in brake thermal efficiency (BTE). Coefficient of variation of IMEP, peak pressure and BTE were deteriorated which limited the usable MDES to 43%.

Diesel particulates are mainly composed of elemental carbon (EC) and organic carbon (OC) with traces of metals, sulfates and ash content. Organic fraction of the particulate are considered responsible for its carcinogenic effects. Diesel oxidation catalyst (DOC) is an important after-treatment device for reduction of organic fraction of particulates. In this study, two non-noble metal based DOCs (with different configurations) were prepared and evaluated for their performance. Lanthanum based perovskite (LaMnO3) catalyst was used for the preparation of DOCs. One of the DOC was coated with support material ceria (5%, w/w), while the other was coated without any support material. Prepared DOCs were retrofitted in a four cylinder water cooled diesel engine. Various emission parameters such as particulate mass, particle number-size distribution, regulated and unregulated emissions, EC/OC etc., were measured and compared with the raw exhaust gas emissions from the prepared DOCs.

Composite structures play a vital role in the automobile industry. Use of composites like CFRPs in automobiles poses various problems to engineers. CFRP components are not simple to model in comparison to traditional engineering materials like aluminium, steel etc. One of the main reason is that the composite materials generally do not behave in an isotropic manner but rather behave in an anisotropic or orthotropic manner. These anisotropic and orthotropic mechanical behaviors are more difficult to predict as compared to isotropic behaviors. This problem is solved using finite element analysis (FEA) packages to model complex composite material and predict their behavior. The paper discusses about the propagation of stresses within the composite laminates using FEA in Abaqus for different lamina stacking directions. The results obtained are verified using Theoretical Analysis in MATLAB.

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.

Application of advance composites in place of the various conventional materials such as steel can give significant weight and performance advantages. The application of composites is now finding it’s way in the automotive industry due to the growing requirement of the lightweight solutions and high strength to weight ratio. However, their low mechanical properties have limited their application in automotive structural components. The study presented here is focused on the explicit dynamic analysis of a bumper beam and advance composites are used for the study. Different configurations and designs of the bumper are considered to be able to make a comparative study of the stress and deformation levels. The analysis was done in coherence to the Euro NCAP tests and the offset frontal impact analysis was done. The boundary conditions were aligned with the real time impact conditions for proper prediction of the results.

Formability of metals and alloys in general and aluminium alloys and steels in particular is of paramount importance in sheet metal forming in automobile industry. It is well understood that the evolution of preferred crystallographic orientation of crystallites or texture during prior thermo-mechanical processing of sheets plays an important role in determining formability. The formability of sheet is measured in terms of the Lankford parameter or the plastic strain ratio which is defined as the ratio of strain in width direction to that in the thickness direction (R = εw/εt). The variation of Lankford parameter with the rolling direction and standard and ΔR value is widely used in industry as a standard for estimating the formability of the rolled sheets.

There is a growing need for improved conceptual vehicle designs along with alternative materials to reduce the damage to the passengers and structures in aerospace and automotive industries. The energy absorption characteristics of materials play a major role in designing a safe vehicle for transport. In this paper, compression behavior and energy absorption of aluminum alloy AA6061 and AA7005 tubes in T4 and T6 conditions are investigated by experimental and numerical methods. The AA7005 and AA6061 tubes are solution heat treated and then aged to achieve the final strength in T6 condition. Experimental compression test results have shown improved energy absorption of tubes in T6 condition compared to tubes in T4 condition. There is less variation of energy among the tested samples. The mean load is compared with the results obtained from analytical formulae. Tensile properties have been obtained from tensile tests using UTM for both AA6061 and AA7005 tubes.