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Automotive suspension system forms the basis for the design of vehicle with durability, reliability, dynamics and NVH requirements. The automotive suspension systems are exposed to dynamic and static loads which in turn demands the highest integrity and performance against fatigue based metallic degradation. The current focus in automotive industry is to reduce the weight of the automotive parts and components without compromising with its static and dynamic mechanical properties. This weight reduction imparts fuel efficiency with added advantages. High-Strength Low Alloy steel (HSLA) offers optimum combination of ductility, monotonic and cyclic mechanical properties. Furthermore, welding processes offer design flexibility to achieve robust and lightweight designs with high strength steels.

Polymers are substituting traditional materials, such as metals, in existing as well as new applications, both for structural and aesthetic applications as they are lightweight, customizable and are easy to mould into complex shapes. With such an extensive use of polymers, there is a need to carefully scrutinize their performance to ensure reliability. This is particularly the case in the automotive and electronic industries where the aesthetic appeal of their products is of prime concern and any visible scratch damage is undesirable. Concern for aesthetics has led to a need for the quantification of visibility due to scratch damage on polymeric surfaces Many painted plastic parts used in vehicles are being replaced with the molded-in color plastics for cost reduction and also due to environmental concerns associated with solvent emissions. There are multiple methods used for scratch evaluation of polymers and paints.

Environmental regulation, operating cost reduction and meeting stringent safety norms are the predominant challenges for the automotive sector today. Automotive OEMs are facing equally aggressive challenges to meet high fuel efficiency, superior performance, low cost and weight with enhanced durability and reliability. One of the key technologies which enable light weighting and cost optimization is the use of fiber reinforced polymer (FRP) composite in automotive chassis systems. FRP composites have high specific strength, corrosion and fatigue resistance with additional advantage of complex near net shape manufacturing and tailor made properties. These advantages makes FRPs an ideal choice for replacing conventional steel chassis automotive components. However, FRP’s face challenges from operating environment, in particular temperature and moisture.

Tailgate stoppers play vital role in exerting preload on the Tailgate latch mechanism and also restrict the relative motion of the Tailgate against vehicle Body in White (BIW). These stoppers act as over-slam dampeners and reduce the transmissibility of vibrations thereby reduce the risk of Squeaks & Rattles (S&R) noises. S&R noises from Tailgate are most annoying to the rear passengers in the vehicle and are recurring in nature. Preventing these issues during design is a challenging task. S&R risk simulations enable us to conduct virtual Design of Experiments (DOEs) and arrive at optimal solutions. This approach helps in reducing the cost of the design changes that are required in the physical prototype at the later stages of product development and save time. The risk evaluation in the simulations is based on the relative displacement at the interfaces of two components.

In recent years, there has been a rapid growing demand for laser brazing in the transportation industry for automotive-Body in White (BIW), steel sheet assembly. Implementation of laser brazing is aimed primarily to improve productivity, quality of joints and cost. Laser brazing works by filling the opening amongst two substrates by melting the filler wire with the help of laser beam (used as a heat source), whereas in conventional resistance spot welding, contacting metal surface points are joined by the heat obtained from resistance to electric current. BIW is essentially a welded metal structure which is meant to provide durability and crashworthiness to the vehicle and is conventionally assembled using resistance spot welding process. The BIW structure comprises of various steel grades having varying thicknesses, compositions, microstructures and mechanical properties.

With the advent of BS VI regulations, automotive manufacturers are required to innovate the powertrains, fuel systems, exhaust and its after treatment systems to meet the regulatory requirements. The exhaust regulations can be met either by reducing the exhaust gases being generated by the engine (attacking the source) or by treating the exhaust gases in after treatment devices. The choice of the opted system varies with the manufacturer. The after-treatment devices such as catalytic converters are generally mounted in the engine compartment to take advantage of high temperature of exhaust gases to yield the reactions. Such an arrangement imposes a lot of thermal load on the peripheral components such as gearshift cables, bearings, oil seals, driveshafts etc. Thermal shields or thermal sleeve are used to address thermal issue and to protect transmission components.

Corrosion testing and simulation has played a critical role in the development of corrosion resistant automobiles. Much has been learned over a period of time with respect to the automotive corrosion protection and its assessment. A range of coatings and platings are being used in the automotive sector. In this field of application, designs are very complex and focus is on enhanced vehicle level corrosion protection, given the high corrosion warranty costs. The objective of the present study was to develop a electrochemical test method to rapidly and quantitatively screen the corrosion performance of automotive coating systems. The present study compares electrochemical results obtained using a linear polarization resistance (LPR) to results obtained via the standard ASTM B117 salt spray test. Salt spray tests were done on a separate series of these coating systems according to ASTM B117, and the results were ranked from 10 (excellent performance) to 1 (very poor performance).

Recycle, Reuse, Repair have become a mantra today for cost reduction. More importantly it reduces the demand of natural resources and helps protect environment. There are many ways in which cutting tools can be recycled. Some examples are used up extra long drill [1] and used up crankshaft grinding wheel [2]. Used up indexable inserts can also be reused by grinding a groove to remove the blunt/dull portion [3], selecting an application where the unused portion of a large cutting edge can be put to reuse [4], reuse by grinding a corner radius to remove the blunt/dull portion [5]. This article explains the concept of reuse of used up tangentially mounted plain inserts and shows that such mounting is best suited for the recycling of indexable inserts and can substantially reduce the tool cost. This recycle can reduce the consumption by almost 50% or more depending on the nature of dullness of insert during the initial use. Conserving natural resources is therefore a good possibility.

Low steering effort in mechanical steering system is very essential, besides meeting the regulatory norms, to have driving comfort and easy maneuverability on turns. All the components in steering and suspension system plays important role in the resultant steering effort of the vehicle. Of all the factors affecting steering effort, following are identified as high influencing parameters: 1 Steering geometry. 2 Steering system compliance. 3 Friction in steering system linkages like assembly steering column, assembly steering gear box etc. 4 Tyre static friction torque. Present paper describes the detailed analysis of the influence of each parameter on steering system. The above parameters were studied in isolation as well as in combination, to ascertain their effect on steering effort. In a mechanical steering system, the parameters listed above contribute to 35% on steering effort where-in frictional forces itself contributes to 25%.

Electrical and Series Hybrid Vehicles are generally provided with single speed reduction gearbox. To improve performance and drive range, a two-speed gearbox with coordinated control of traction motor and gearshift actuator is proposed. For a two-speed gearbox, gearshift without clutch would increase the shifting effort. Active Synchronization is introduced for a smoother gearshift even without clutch. The quality of gearshift is considered as a function of applied shift force and time taken. To enhance the quality of the gearshift further, the location of the synchronizer in the transmission system is optimized. To validate the improvement in the quality of the gearshift, a mathematical model of the two-speed gearbox incorporating proposed location of synchronizer assembly along with active synchronization is developed. The qualitative and quantitative analysis of the results achieved is presented.

Comfortable cabin environment from temperature, noise and vibration point of view is one of the most desirable aspects of any vehicle operating in hot or cold environment. Noise generated from HVAC system is one of the most irritating phenomena resulting in customer dissatisfaction and complaints. It becomes absolutely necessary to have low HVAC noise levels when the target market has hot weather all round the year. Balance between control of temperature in desired way with least possible noise and vibration is the key for HVAC performance optimization within constrains posed by design and cost. This paper describes the approach for NVH refinement of front HVAC system proposed for a vehicle with limited off-road capability for which packaging constraints and late changes related to airflow and HVAC unit design for meeting comfort and crash requirements resulted in deterioration of noise and vibrations while operation.

This paper is related to a vehicle with rear engine which is turbo charged and inter cooled. Due to packaging constraints the intercooler was placed in front of turbocharger and was exposed to hot air radiated out from the turbo charger. This was in turn reducing the efficiency of the intercooler. In such scenario, it is essential to shield the turbo charger from the intercooler for proper hot air management. Also rear engine vehicles don't have the benefit of ram air affect. This necessitates increasing the air entering in to the core of the intercooler. Both the above mentioned issues associated with such a vehicle was resolved by ensuring that the hot air from turbo-charge is guided away from the intercooler as well as the air flow to Intercooler is increased. Guiding or throwing out the hot air away from Intercooler was done by introducing a heat shield or a baffle between the two.

Automotive suspension system forms the basis for the design of vehicle with durability, reliability and NVH requirements. The automotive suspension systems are exposed to dynamic and static loads which in turn demands the highest integrity and performance against fatigue based metallic degradation. The growing demand for light-weighting has culminated into numerous designs of rear twist beam suspension systems. However these designs drive their design flexibility by incorporating multiple welding joints into the suspension system. Welding joints helps in designing complex automotive systems. However, these welding joints bring in weak points as welding process itself degrades parent material and introduces areas with high tensile residual stresses. These areas with tensile residual stresses are susceptible to undergo fatigue failure. Thus, there is a need to improve welding process to mitigate harmful tensile residual stresses.

The sunrise vision for hydrogen economy lies in efficient, lightweight and durable devices which can convert hydrogen energy into electrical energy. Proton Exchange Membrane fuel cell (PEMFC) is a key hydrogen energy conversion system for transport sector. The efficiency and durability of PEM fuel cell largely depends on cathode electrode and membrane and Bipolar plates (BP Plates) plays an important role in it. BP plates perform the important functions of transporting fuel gases to reactive sites, collecting charges and thus conducting electricity from cell to cell, moisture adjustment of membrane, transport of produced water and provides essential mechanical strength to fuel cell stack. It makes BP plates the backbone of PEM Fuel cell power stack. For BP plates to perform intended functions, it is highly desirable BP plates to possess excellent properties on corrosion resistance, electrical conductivity, thermal conductivity, water wettability, weldability and formability.

Reckoning today's environmental rules, legislative regulation and market requirements- the automotive industry of late has witnessed an increased vigor and enthusiasm by auto makers towards electrification of vehicles across all platforms in a bid to improve fuel economy and performance. Hybridization of a vehicle often involves the use of expensive high performance motors and large battery packs. However due to the challenges associated with the packaging of bulky battery and motor systems in existing drive train, mild hybrid systems have been preferred over strong or full hybrids especially in current production models as they don't entail any major change in architecture and the reduced battery size, both of which provide for easier packaging of components.

The automotive industry is facing a challenge as efficiency improvements are required to address the strict emission norms which in turn requires high performance downsized, lightweight IC engines. The increasing demand for lightweight engine needs high strength to weight ratio materials. To meet high strength to weight ratio, castings are preferable. However due to strength limitations for critical crankshaft applications, it forces to use costly forgings such as micro alloyed forging steel and Martensitic (after heat treatment) forging steel. To reduce the cost impact, high strength Austempered Ductile iron (ADI) casting is developed for crankshaft applications to substitute steel forgings. Austempered Ductile Iron is having an excellent mechanical properties due to aus-ferritic structure. The improved properties of developed ADI Crankshaft over steel forged crankshaft offers additional weight advantage.

Corrosion in automotive industry is broadly categorized into cosmetic & perforation corrosion. Cosmetic corrosion comprises of superficial red rust which is deleterious to the overall aesthetic appeal of the vehicle but can be rectified. Perforation corrosion involves complete erosion of the panel, compromising structural integrity of the respective part. Perforation corrosion demands part replacement. In order to tackle this menace, automotive OEMs have formulated varied corrosion strategies in terms of selection of appropriate substrate, part design & surface protection scheme. Validation of various corrosion strategies become pivotal during the development phase of various parts and assemblies. Traditionally, Salt Spray Test (SST) has been used to determine corrosion life of materials/parts/assemblies. This test however does not simulate real-world conditions.

Structural automotive components are subjected to fatigue damage under cyclic stresses and strains. The fatigue damage initiates at stress levels lower than the elastic limit of the material and results in cracks. The Initial fatigue cracks are difficult to detect, such cracks can develop rapidly and cause sudden and brittle failure in structures. Many structural automotive components are fabricated involving weld induced local conditions such as geometry of weld toe and localized tensile residual stresses. These conditions are favorable for initiation of fatigue damage at weld toe. In current work, sever plastic deformation (SPD) which is based on high frequency impact treatment using ultrasound energy was applied on weld toe of representative weld joints. The effect of SPD on weld toe geometry modification, microstructure and residual stresses were evaluated. Microscopic and X-ray diffraction techniques were used to study the effects of SPD.

A lightweight multi-material combination of steel and aluminium alloy (Al) is becoming a novel approach towards environmentally sustainable transport systems. Studies show that 10% reduction of vehicle weight results into 3-7% reduction in specific fuel consumption in IC engines and a 13.7% improvement in electric range for electric vehicles. However, dissimilar welding of Al/steel is a key challenge because of incompatible thermo-physical properties (melting point, thermal conductivity, and coefficient of thermal expansion) and low miscibility between Al and steel. The formation of brittle and hard Al-steel intermetallic compound (IMC) at the joint interface is the major concern for dissimilar welding of Al/steel. In this work, efforts are made to check the feasibility of Ni interlayer to control IMC formation at the interface of Al/steel dissimilar welded joint. Resistance spot welding is used to join low carbon steel CR01 and Al AA6061-T6 with pure Ni interlayer.

The usage of forging a preformed, near net shape, compacted and sintered metal powder has been widely accepted since the eighties and is now one of the mainstays for producing Connecting rods in North America. However, its use in Indian subcontinent is limited as its counterpart i.e. conventional steel forging is still the most dominant. Powder metallurgy route has many advantages like good dimensional accuracy; minimum scattering of weight etc. Despite these advantages, the Powder metallurgy process is still not preferred predominantly due to technical (endurance) and infrastructural limitations. This work envisages combining the benefits of powder metallurgy process with the required mechanical properties viz. tensile and fatigue strength alongside design modifications to meet the requirements of a connecting rod for a 2-cylinder diesel engine. The connecting rods met the fatigue life at the required FOS equaling the performance of a conventionally forged connecting rod.