Fender Design

IM:

The aim of these project is to design fender and the main design requirements for Drip area, Bumper, A pillar and Sill mounting areas.

INTRODUCTION:

Aluminum automotive components made using a hot blow forming process are reducing vehicle weight and increasing the fuel efficiency of today’s cars. However, before General Motors (GM) and the Department of Energy (DOE) sponsored research in this technology, blow forming of aluminum was not a viable process for automakers. The prior blow forming process called superplastic forming (SPF), was not suitable for the industry’s high-production-rate demands, and the materials required for SPF were too expensive three times the cost of standard, non-SPF, aluminum sheet metal. Therefore, bringing SPF to the automotive industry required developing low-cost SPF alloys and faster forming cycles. Reducing the cost of SPF alloys also required demonstrating the viability of SPF to both the automotive and aluminum industries. DOE initiated a program of joint-funded research between GM and Kaiser Aluminum, with the Pacific Northwest National Laboratory (PNNL) providing a catalyst to encourage GM to develop aluminum blow forming processes. Based on early research, General Motors recognized the inherent limitations of superplastic forming and moved forward with the commercialization of an advanced blow forming process, called Quick Plastic Forming. The result is cost effective, higher-volume manufacturing technology that is producing lightweight components for today’s automobiles. With the recognition of environment, all the governments have the strict standard of the letting epilogue. So, reducing the heavy is becoming the key of automobile development. One of the means of reducing the heavy of automobile is using the aluminum alloy and magnesium alloy. Aluminium, for its low density compared to steel, is the most promising material for achieving weight savings in future automotive body structure. Aluminum alloy has larger spring back and the lower plasticity; all of characters are difficulty for the stamping of complex shape of aluminum alloy car. As well known, Aluminum alloy is one of the superplastic materials which have longer elongation and no spring back under the superplastic state . These advantages of superplastic forming (SPF) process are the possibility to realize very complex part in one single operation and the low tooling costs . According to the capability of aluminum alloy and the advantages of SPF, a study of Finite Element Analysis (FEA) of superplastically formed front fender of aluminum alloy has been carried out. Considering the cost of the formed part, a commercial aluminum alloy sheet 5182 i.e. its material properties, which are used in FEA of stamping process of car panels, is selected as analytical material. The front fender of an all aluminum micro car . The dimension of the front fender is 916mm×181mm×710mm.

Outer of car :

Fender :

Fender is a front outer side member of a car which covers the wheel side. Fender purpose is to prevent sand, mud, rocks, liquids and other particles.

Fender is a closure component, closing the engine compartment and other compartments. The major role of the fender is to avoid the chipping inside the engine compartment. During the motion the wheel picks a sand mud and small stone particles and throws it inside the car and these fenders will be helpful in preventing them by hitting inside the engine compartment and car body. These fenders will have a plastic part which lies on wheel arch area. The fender plays a major role to avoid problems for pedestrian also.Fender are typically rigid and can be damaged by contact with the road surface. It is often also called as Mudguard.

Types of fender :

• Full Bumper Type.
• Half Bumper Type.

Full Bumper type :

It is not used now a days because they requires bigger size blank to produce the part and the large scrap is also produced.

Half Bumper Type :

Half bumper types are used in present and future also because the blank size is less and the wastage or scrap is less comparing to full bumper type fenders.

Uses of car Fenders :

• Car Fender limit the exposure of your car's body and engine to external elements that are harmful.
• Fender flares are attached to ensure that both the body and engine have minimal contact with corrosive elements
• Car Fenders provides safety to the driver and the passengers at the time of accidents or collisions. They are manufactured in a way to provide bend during front and side collisions.
• Car Fenders are designed to avoid wind resistance and make your car more aerodynamic.
• Car Fender enhance the overall look of your cars. Fender flares are available in distinctive designs in the market. Mostly you find universal Fender flares, but you can get customized cars Fenders to fit your car wheels.

Areas to be considered while designing a fender :

1. Drip area
2. Bumper mounting area
3. Sill mounting area
4. A pillar mounting area

Drip area :

Drip area mounting is the important part in the fender . this mounting is attached to the engine compartment of the car . fender drip area is mounted via weldnuts to the engine compartment .a min of 150mm distance is kept from the front side and a distance 300mm or less can be kept on the rear side . the total length of drip area from the top of fender should be less than 40mm , this is to avoid the springback during the manufacturing . the edge of the mounting should atleast 10mm away from any nearby component in the engine . a rigidity bead is provided at the end to increase the strength of the mounting .

Bumper mounting area :

Sometimes fender is also provided with the cowl area mounting . this mounting is on the top side of the fender .

A-pillar mounting area :

The A-pillar area mounting depends upon the A-pillar of the car . the mounting can also be provided with ribs to strengthen the part . this mounting is critical in design as it has to be mounted on A-pillar properly.

Sill mounting area :

Sill area mounting is also an important mounting part .this mounting point is basically on the bottom of the fender . the mounting part should be created such that the fender is firmly attached to the sill .

FENDER DESIGN:

GIVEN FENDER SURFACE:

The side faces of the fender is splitted to create mouting surface, to create flanges in drip area,sill mounting,A Pillar , bumber and wheel arch area.

Steps done to create the mounting flanges :

• Boundary
• Parallel curve
• Points
• Spline
• Join
• Split

MASTER SECTION FOR DRIP AREA:

Considering the above design constrains we have to design the drip area. Embosses are provided to increase strength, corners of the flanges are smoothen to ease of the production. Uniform wall thickness of 0.75mm.

• Design Consideration for drip area are150mm distance from front end of the fender and the gap is filled with headlamp 200mm distance from rear end of the fender and the gap is filled with wiper motor assembly.
• Initially 3-degree angle and 9mm length is given while creating a drip area because the engine component should not be visible from outside.
• The depth of the drift should be between 40 to 60mm. If the depth exceeds from 60mm then forming is not feasible due to spring back and wrinkles.

Embosses and ribs are given to drip area to give strength. Embosses dimensions are depth 5 mm and 10 degree of angle for all three embosses.

Creat hole along with embosses for mounting with engine compartment using fastners.

A PILLAR AREA:

A Pillar is on the cars either side of the front windshield which is the reason the windshield in the place.

It is Mounted on the A Pillar by means of fasteners and these are covered by outer side view mirrors.

Here, the proper embossing are provided along with holes for fasteners.

Sweep from the split edges in the A pillar area for dimensions are 42mm length and 90 degree of angle.Creating a sketch and extrude should intersect with sweep face and split it.again sweep in splitted edges used 6mm length and 80 degree of angle.Offsetting the sweep face 5mm.Trim sheet to create a hole of 5mm diameter.Edge fillet and surface fillet are 2mm.

SIL MOUNT AREA:

The Sill Mounting area is in the bottom of the fender. It is mostely gets connected with the door region of the car.Here, proper embossing and holes for the fasteners are provided.

Sweep from the egdes of sill mount area for 42mm length and 90 degree of angle.Creating a sketch and extrude should intersect with sweep face and split it.again sweep in splitted edges used 6mm length and 80 degree of angle renference with surface.Offsetting the sweep face 5mm.Trim sheet to create a hole of 5mm diameter.Edge fillet and surface fillet are 2mm.

BUMPER MOUNTING AREA:

In this Mounting, the Fender connects with the bumper.

The Bumper Mounting region must be rigid in order to withstand the force acting upon it during collision. So, the Mounting space can be larger

Sweep from the egdes of bumber mounting area for 50mm length and 90 degree of angle.Creating a sketch and extrude should intersect with sweep face and split it.again sweep in splitted edges used 6mm length and 80 degree of angle renference with surface.Offsetting the sweep face 5mm.Trim sheet to create a hole of 5mm diameter.Edge fillet and surface fillet are 3mm.

BAFFLE AREA:

Creating holes for baffles(wheel arch).

create holes of 5mm in the splitted face in the wheel arch area.

FINAL FENDER SOLID COMPONENT:

MULTI VIEWS OF FRONT FENDER:

CONCLUSION:

Here, developed mounting flanges in Drip area, Sill mount, A pillar and Bumber with given design requirements.