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In present study a comparative investigation and correlation attempted on small scale vehicle model for aerody-namic drag performance at small scale wind tunnel test facility in India vs full vehicle tested at globally know and accepted full scale test facility in Pininfarina, Italy. Current investigation aims to assess the small-scale wind tunnel suitable for testing 1:3 small scale car models A scale model of 1:3 scale size was tested in small scale wind tunnel (at IISC,Bengaluru, India) having test section area of 11.68 Sq. m. To understand the overall vehicle aerodynamic drag performance small scale model was test-ed for different configurations such as baseline, spoiler removal, underbody cover and different yaw condition. To understand the correlation between small scale vs full vehicle’s aerodynamic performance one actual vehicle was also tested at full scale wind tunnel Pinifarina Italy.

Foundry industries are very much familiar and rich experience of producing ferrous castings mainly Flake Graphite (FG) and Spheroidal Graphite (SG) cast iron. Grey cast iron material is mainly used for dampening applications and spheroidal graphite cast iron is used in structural applications wherein high strength and moderate ductility is necessary to meet the functional requirements. However, both types of cast iron grades are very much suitable in terms of manufacturing in an economical way. Those grades are commercially available and being consumed in various industries like automotive, agriculture etc, High strength SG Iron grades also being manufactured by modifying the alloying elements with copper, chromium, manganese andcobalt. but it has its own limitation of reduction in elongation when moving from low to high strength SG iron material. To overcome this limitation a new cast iron developed by modifying the chemical composition.

The maximum power produced by the Engine is utilized in overcoming the Aerodynamic resistance while the remaining has been used to overcome rolling and climbing resistance. Increasing emission and performance demands paves way for advanced technologies to improve fuel efficiency. One such way of increasing the fuel efficiency is to reduce the aerodynamic drag of the vehicle. Buses emerged as the common choice of transport for people in India. By improving the aerodynamic drag of the Buses, the diesel consumption of a vehicle can be reduced by nearly about 10% without any upgradation of the existing engine. Though 60 to 70 % of pressure loads act on the frontal surface area of the buses, the most common techniques of reducing the drag in buses includes streamlining of the surfaces, minimizing underbody losses, reduced frontal area, pressure difference between the front & rear area and minimizing of flow separation & wake regions.

Aerodynamics of on-road vehicles has come to the limelight in the recent years. Better aerodynamic design of vehicle would improve vehicle fuel efficiency with increased acceleration performance. To obtain best aerodynamic body, the series of design modifications and different testing methodologies must be involved in vehicle design and validation phase. Wind tunnel aerodynamic force measurement, road load determination and computational fluid dynamics were the common methods used to evaluate the aerodynamic behavior of the vehicle body. As a novel approach, the present work discusses about the on-road (Real time) testing methodology that is aimed to evaluate the aerodynamic performance of vehicle body using surface pressure mapping. A 64-Channel digital pressure scanner has been utilized in this work for mapping the pressure at different locations of the typical vehicle body.

The input shafts are conventionally developed through Hot forging route. Considering upcoming new technologies the same part was developed through cold forging route which resulting in better Mechanical properties than existing hot forging process. It has added benefit of cost as well as environmental friendly. Generally, the part like Input shaft which having gear teeth, splines etc., will be manufactured through Hot forging process due to degree of deformation, availability of press capacity, diameter variations etc., This process consumes more energy in terms of electricity for heating the bar and also creates pollution to the atmosphere. Automotive input shaft design modified to accommodate cold forging process route to develop the shaft with press capacity of 2500T which gives considerable benefit in terms of mechanical and metallurgical Properties, close dimensional tolerances, less machining time, higher material yield when compared to hot forging and metal cutting operation.

This paper deals with an analytical method to calculate the press-fit tolerance and fits between gears and shaft for automotive applications. The relative interferences increase sharply in the small diameter range, therefore one must be especially careful when designing small diameter joints. The strength of press-fit depends on the amount of relative interference; extreme interference leads to excessive contact stresses between the gear and shaft eventually leading to failure. Too little interference leads to slippage of gear on the shaft. In the press fit connection a shaft's spline rolling operation and gear internal broaching is eliminated. It is more economical than a conventional spline connection. Press fit connections are used in various transmission between a shaft and a gear. They are used in 6 speed transmission to 9-speed transmission for (German based Vehicle Manufacturer) heavy and light commercial vehicle company.

Plastics are prone to photo oxidative and thermal oxidative degradation under usage conditions due to their chemical nature. From sustainability and cost standpoint, there is an increasing focus on Mold-In-Color (MIC) plastic materials. Simultaneously customer’s expectations on the perceived quality of these MIC parts has been increasing with attractive color and glossy appearance. A study was conducted to analyze the product quality and durability aspects over a prolonged exposure to accelerated weathering condition. Material selected for this study were injection molded specimens of ABS and PC-ABS used in automotive passenger vehicles. Comparative analysis was conducted before and after weathering exposure at defined intervals by using Fourier Transform infra-red spectrometer (FTIR), differential scanning colorimetry (DSC), universal testing machine (UTM), Izod impact tester and microscope to understand the impact on their chemical and mechanical properties.

With increasing road traffic and pollution, it becomes responsibility for all OEM to increase fuel efficiency and reduce carbon footprint. Most effective way to do so is to reduce weight of the vehicle and more use of ecofriendly recyclable material. With this objective we have come up with Light weight, cost effective sustainable design solution for Injection moulded RQT (Rear quarter trim). It is an interior plastic component mounted in the III row of the vehicle. This is required to ensure inside enhanced aesthetic look of the vehicle and comfort for 3rd row passengers. Conventionally RQT of vehicle with 3rd row seating is made using plastic material (PP TD 20). With the use of plastic moulded RQT there is a significant weight addition of around 6 kg per vehicle along with reduced cabin space, huge investment and development time impact.

Utility or Off-road vehicles are characterized with their higher ground clearances. Higher ground clearance of vehicle requires the vehicle to have footsteps for easy entry and exit of passengers from the vehicle. A typical foot step construction consists of structural steel brackets with an Aluminum or plastic top panel. Conventional steel construction is heavier to meet weight bearing capacity and durability requirements. Our objective of this work is to explore lightweight materials which can meet these performance requirements with a lighter construction. We chose to study the continuous glass fiber reinforced plastic as an alternative to the metal construction.

The spoiler is functional as well as aesthetic part fitted on the vehicles to improve the vehicle aerodynamic performance and better aesthetic appeal. The improvement of aerodynamics performance of the vehicle at higher speeds is achieved by reducing the overall vehicle coefficient of drag. This helps in better handling and improved fuel efficiency of the vehicle thus contributing to development of greener vehicle. In this project, our main focus is to reduce overall vehicle coefficient of drag, Design a light weight spoiler and improve the vehicle aesthetic appearance.

Mechanical and wear properties of Al alloyed gray cast iron (0.5% and 1.0%) were compared with that of Mo (1.0%) and Cu (0.77%) alloyed gray cast iron in this investigation. All the alloys showed pearlitic microstructure. The graphite morphology varied due to varying chemistry. The fracture surface showed “cabbage” like dimpled morphology indicating the predominant ductile fracture. It was found that the Mo containing cast iron show 25 to 30% higher strength and 6 to 7 times better wear resistance compared to Al containing cast irons. The worn surface showed oxide formation during sliding.

Tensile Testing is one of the most used and highly reliable method of mechanical testing to evaluate the tensile properties of the material. However, there is a large scope for discussing the behavior of the metals based on the direction of rolling and the tensile specimen size used for testing. This paper discusses the variation observed in the tensile values along the direction of rolling and traverse to the direction of rolling for S460MC. It also evaluates the variation observed in the values based on the various gauge lengths (GL) commonly used in testing as per international standards (80mm, 50mm and 25mm GL). It is observed that perpendicular to the direction of rolling, the Yield and Tensile strength of the material increase marginally while the Elongation percentage (%E) decreases by a small margin irrespective of the gauge length taken into consideration.

Automotive steel wheel is a critical component for human safety. For validating steel wheel various tests will be performed at component and vehicle level. Cornering test performed at vehicle level is one of the tests, where wheel will be validated for high cornering loads. Cornering test performed at vehicle level consists of three different events i.e., rotations of vehicle in track1, rotations of vehicle track 2 and rotations of vehicle in track3. As wheel will experience different loading in each of the events of cornering test, correlating the virtual Finite Element Analysis (FEA) with physical test is quite challenging. If in FEA we can predict the damage and life very near to the physical validation, we can create a safe wheel for high cornering loads without any test concerns. Vent hole shape and Hat depth are two important aspects in wheel disc design. Vent hole shape and size will influence the heat dissipation of braking.

The brass synchronizers are not resistant to abusive conditions of gearbox operations, but they are very durable and cheap when used on their favorable material property working limit. The main failure which can occur in the gearbox due to the synchronizer is crash noise. During gear shifting the gear crash will create high discomfort for the driver and must apply high force to change the gears. The main factors which contribute to the crash phenomenon are the insufficient coefficient of friction, high drag in the system, and high wear rate of the synchronizer rings before the intended design life of the synchronizer. The brass synchronizers were tested on the SSP-180, ZF synchronizer test rig to know the effect of the synchronizer performance parameters like the coefficient of friction, sleeve force, slipping time as well as durability parameters like wear rate when the operating temperature of the oil is changed.

In most cases, the properties of a metal are evaluated in their as rolled condition, prior to any work hardening or bake hardening. But in the Automotive World, these steels get work hardened during the forming process and bake hardened in the paint shop. The goal of this paper is to evaluate the variations in the performance of Dual Phase (DP) steels and understand the most optimized method of testing and property generation. This method can then be used to extrapolate to real automotive components. Dual Phase Steels or DP Steels contain a mixture of Ferrite & Martensite from which they derive their name. They are a part of the advanced high strength and ultra-high strength steels steel family according to World Auto Steels. The Ferrite phase, with its iron content contributes to the material displaying an increased level of ductility whilst, the martensitic phase provides the steel with increased mechanical strength.

Weight reduction in automotive applications have led to the processing of thermoplastic polymers by foam injection molding. The density of the foamed polymer can be reduced up to 20%. Whilst, work has been reported on the weight reduction of the foamed polymer by using different types of blowing agent technologies, there has been limited studies in the areas of the sound transmission loss and sound attenuation properties of these materials. The present study is intended to understand the effect of chemical blowing agent (CBA) on the properties of polypropylene. The molded specimens were characterized using density, Differential scanning colorimetry (DSC), Thermogravimetric analysis (TGA), Fourier transform infra-red spectroscopy (FT-IR) and sound transmission loss (STL) measurements. Specimens were also tested for tensile properties, flexural properties, Izod impact strength and Heat deflection temperature (HDT) as per standard test protocol.

Restraint systems in automotives are inevitable for the safety of passengers. Seat belts are one such restraint system in automotives that prevent drivers and passengers from being injured during a crash by restraining them back. Seatbelt on automotives has interface with Body-in-white (henceforth called as BIW) and Trim parts in-order to serve its purpose at vehicle level. One such interface part of seat belt is the web guide, which assists and ensures the nylon web’s smooth motion at different seat track positions. Web-guides on automotives ensure the flawless motion of seat belt web at pillar trim areas. In this paper, we are discussing alternate ways of assisting the seat belt web without the web-guide as a separate part. In-order to assist and ensure the motion of nylon web in its trajectory, we have extended the flange of the pillar trim involved.

The strength and wear resistance of four alloyed cast irons with elements like Ni. Mo, Cu, Cr and Al have been compared and analyzed. The increased hardness is reducing the wear resistance of the alloy due to graphite flakes. Higher carbon produces more graphite flakes which act as weak points for reducing strength and wear resistance. The wear rate increases for harder cast iron sample with more graphite flakes. Wear rate drastically increases with increase in carbon equivalent. Strength was found to decrease for samples with higher graphite flakes. The wear debris consisted of graphite flakes in platelet like morphology along with iron particles from the matrix. The presence of carbon at the sliding interface also sometimes decreases wear rate.

In this paper, mold in color diamond white ASA material has been explored for front bumper grill, fender arch extension, claddings and hinge cover applications. Other than aesthetic requirements, these parts have precise fitment requirement under sun load condition in real world usage profile. Structural durability of the design was validated by virtual engineering. Part design and material combinations with better tooling design iterations were analyzed by using mold flow analysis. Complete product performances were validated for predefined key test metrics such as structural durability, thermal aging, cold impact, scratch resistance, and weathering criteria. This part met required specification. This mold in color ASA material-based parts has various benefits such as environmentally friendly manufacturing by eliminating environmental issues of coating, easily recycled, and faster part production because intended color achieved in one step during molding.

Aesthetics contribute significantly to the customer’s buying decision of an automobile. This is traditionally achieved through painting. Sustainability and cost challenges have led automakers to look at substituting painting through molded-in color polymers in decorative bezels like pillar appliques. These appliques and bezels have a unique mix of material requirements that include color tone, gloss, stiffness, scratch resistance and weathering. Polycarbonates are an interesting class of polymers that has the potential to meet these challenging requirements. This paper reports the work done in evaluating a polycarbonate compound in piano black shade to meet the functional and aesthetic requirements. The results prove that the material can substitute painting thereby resulting in significant cost savings. This is a ready to mold material used in injection molding process. This modified polycarbonate material has been explored for thin wall appliques and bezels with thickness of 2.7 mm.