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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 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.

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.

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.

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.

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.

In automotive Body-In-White (BIW) structures, stiffness and the fatigue behavior is greatly influenced by the properties of its joints. Spot welding is one of the most widely used process for joining of sheet metals in BIW. Spot weld fatigue life under Accelerated Durability Test (ADT) is crucial for durability performance of BIW structures. Experience of BIW validations highlighted more number of spot weld failures in CAE when compared to actual tests. Hence, lot of iterations in the form of design modifications are required to be carried out to make these spot welds meet the targets which increases design & development time as well as cost. Current practice uses force-based approach for predicting spot weld fatigue life in CAE. To improve the spot weld fatigue life correlation, extensive study has been carried out on the approaches used for calculating spot weld fatigue life, namely force & stress-based approaches.

A major challenge to automotive industry is to protect the vehicle from corrosion in varying environments with respect to different service conditions. One of the main types of corrosion that affects aesthetic look is edge corrosion on sheet metal. Mostly edge is acting as starting point of corrosion due to unprotected metal exposed to environment. Special attention needs to be given to exposed edges to protect from rust formation. Samples were prepared as per design of experiments with respect to manufacturing process condition, material usage, and design. These samples were tested for corrosion test and painting process compatibility. In this study effect and limitation of burr and optimum solution with respect to corrosion was evaluated and results will be discussed.

In sheet metal painting for various applications like tractor and automobiles, most attractive coating is metallic paints. It is widely applied using 3 coat 2 bake or 3 coat 1 bake technology. Both options, results in high energy consumption, higher production through put time and lower productivity in manufacturing process. During various brainstorming and sustainability initiatives, paint application process was identified to reduce burden on environment and save energy. Various other industry benchmarking and field performance requirement studies helped to identify critical quality parameters. There was collaboration with supplier to develop monocoat system without compromising any performance and aesthetic properties. This resulted in achieving better productivity, elimination of two paint layers, substantial reduction in volatile organic content, elimination of one baking cycle and energy saving.

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.

Piston is a critical component of the engine as it exposed to high inertial and thermal loads. With the advent of high performance engines, the requirement of the piston to perform in extreme conditions have become quintessential. Piston scuffing is a common engine problem where there is a significant material loss at the piston and the liner, which could drastically affect the performance and the longevity of the components. This detrimental phenomenon would occur if the piston is not properly designed taking into consideration the thermal and structural intricacies of the engine. A water-cooled gasoline engine which had significant wear pattern on its piston skirt and liner was considered for this study. The engine block was made of aluminum alloy with a cast iron sleeve acting as liner. The piston-liner system was simulated through a commercially available numerical code which could capture the piston's primary and secondary motion.

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.

This study on optimum magnification at which Retained austenite to be evaluated by comparing the difference in determining the retained austenite in low carbon carburizing alloy steel using the optical metallurgical micrographic method and X-ray diffraction method. The retained austenite phase will be in surface and color is white in nature also its presented in between the martensite needles. It can be distinguished as separate micro-constituents by using image analyzing software. In another method the RA measurements were carried out on the surface by PROTO iXRD Retained austenite measuring system using Cr K radiation. The (211) and (200) reflections of Martensite and (220) and (200) reflections of Austenite were made for this estimation. However, the calculated values of retained austenite by metallurgical microscope in different magnifications are not identical.

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.

This paper deals with new trends in materials & heat treatment in automotive transmission shafting. The material is S48C a low carbon alloy steel and material for automotive shaft special significance as it reduces overall cost in vehicle transmission shafts. Conventional method of shaft heat heat-treatment is case hardening for 20MnCr5. S48C is low-carbon alloy steel. This is an alternate proposal to 20MnCr5.There are lot of advantages in induction hardening over case hardening. Also induction hardening process with S48C material becomes cheaper than case-hardening with 20MnCr5.Strength and resistance to stress must therefore be carefully considered during the material selection and heat-treatment process. We have done Static torsion test for 20MnCr5 (case hardened steel) and S48C (induction hardened shaft). Test results were comparable with 20MnCr5 (case hardened steel). Also after test a metallurgical inspection was done on an S48C (induction hardened shaft).

Shift quality of a manual transmission is a critical characteristic that is requires utmost care by the designers while structuring the transmission. Shift quality is affected by many factors viz. synchronizer design, shift fork design, shifter design, gear design, transmission oil selection etc. Designers have realized that shift fork is critical element for improving shift feel of a transmission. This paper focuses upon the reduction in weight of the overall transmission shift system by using steel inserts in aluminum shifter forks. No compromise on the stiffness and strength of the shift fork of a manual transmission is done. Stiffness and strength of shifter fork is optimized using contact pattern analysis and stiffness analysis on MSC Nastran. All the subsystem (i.e. synchronizer and the shift system component) are constrained to optimize the shift fork stiffness. A 5-speed manual transmission is used as an example to illustrate the same.