Description:. DESCRIPTION:
Field of the invention:
[0001] The present disclosure generally relates to the technical field of automotive roof panels, and in specific, relates to fabricating an automotive roof panel using carbon fiber reinforced polymer composite with carbon fiber powder to reduce weight of the roof panel and provide bending stiffness and impact strength.
Background of the invention:
[0002] An automotive roof panel is a critical component of any vehicle, and its design and construction are essential to the overall performance and appearance of the vehicle. The automotive industry is constantly seeking innovative ways to improve the performance and efficiency of vehicles. One major disadvantage of automotive roof panels is their weight. The heavier the roof panel, the more fuel the car will consume, which can lead to higher operating costs and increased emissions.

[0003] Additionally, heavy roof panels can negatively impact a car's handling and performance. Another disadvantage is that some types of roof panels, such as glass or plastic ones, may be more prone to cracking or shattering in extreme weather conditions. This can pose a safety risk to passengers inside the car.

[0004] Typically, the automotive roof panel is made of lightweight materials such as aluminum or composite materials, which helps to reduce the overall weight of the vehicle and improve fuel efficiency. In addition to its functional role, the roof panel also plays a significant role in the overall design of the vehicle. It can be shaped and styled in a variety of ways to create a unique and visually appealing look.

[0005] The use of polymer-based composites in the manufacturing of automotive roof panels has been gaining popularity in recent years due to their lightweight and durable properties. The feasibility of replacing heavy-weight roofs with these composites can potentially lead to improved fuel efficiency and reduced emissions. Carbon fiber reinforced polymer is one of the polymers that is used in the manufacturing of automotive roof panels.

[0006] CFRP, or carbon fiber reinforced polymer, is a lightweight and strong material that is commonly used in aerospace and high-performance sports equipment. By using lightweight material, a carbon footprint is reduced to increase fuel efficiency. Reducing the weight of the vehicles can increase the operating range in the case of EV vehicles to achieve extra miles per charge. By incorporating this material into automotive roof panels, manufacturers can reduce the weight of the vehicle, resulting in improved fuel efficiency and handling. The hybrid composite involves combining CFRP with other materials.

[0007] In addition to the practical benefits, the use of CFRP hybrid composite materials also adds a sleek and modern aesthetic to the vehicle. The unique texture and finish of the material can enhance the overall design and appeal of the car. Overall, the use of CFRP hybrid composite materials for automotive roof panels is a promising solution for improving vehicle performance, efficiency, and design.

[0008] However, there are a few disadvantages to using CFRP in automotive roof panels. Firstly, CFRP is an expensive material compared to traditional materials such as steel or aluminum. This can increase the overall cost of the vehicle, making it less accessible to the average consumer. Lastly, CFRP is not as easily recyclable as traditional materials. This can have a negative impact on the environment, as the material may end up in landfills rather than being reused.

[0009] Therefore, there is a need to develop a carbon-fiber-reinforced polymer composite for an automotive roof panel that enhances bending stiffness and impact strength and reduces the weight of the roof panel. There is a need to develop a lightweight carbon-fiber-reinforced polymer composite for an automotive roof panel in place of heavy-weight roof panels by using polymer-based composites instead of conventional materials. Further, there is a need to develop a carbon-fiber-reinforced polymer composite for an automotive roof panel that uses industrial wastes to reduce the manufacturing cost, material cost, disposal problems and mainly environmental pollution issues raised by industrial wastes.

Objectives of the invention:
[0010] The primary objective of the invention is to develop a lightweight automotive roof panel in place of heavy-weight roof panels by using polymer-based composites instead of conventional materials.

[0011] Another objective of the invention is to develop a carbon-fiber-reinforced polymer composite for an automotive roof panel that uses industrial wastes to reduce the manufacturing cost, material cost, disposal problems and mainly environmental pollution issues raised by industrial wastes.

[0012] Further objective of the invention is to develop a carbon-fiber-reinforced polymer composite that reduces the weight of an automotive roof panel and improves the bending stiffness and impact strength of the roof panel.
Summary of the invention:
[0013] The present disclosure proposes a material selection and manufacture of automotive roof panel using CFRP hybrid composite. The following presents a simplified summary in order to provide a basic understanding of some aspects of the claimed subject matter. This summary is not an extensive overview. It is not intended to identify key/critical elements or to delineate the scope of the claimed subject matter. Its sole purpose is to present some concepts in a simplified form as a prelude to the more detailed description that is presented later.

[0014] In order to overcome the above deficiencies of the prior art, the present disclosure is to solve the technical problem to fabricate an automotive roof panel using carbon fiber reinforced polymer composite with carbon fiber powder to reduce weight of the roof panel and provide bending stiffness and impact strength.

[0015] According to an aspect, the invention provides a lightweight automotive roof panel in place of heavy-weight roof panels by using polymer-based composites instead of conventional materials. In one embodiment herein, the carbon-fiber-reinforced polymer composite for an automotive roof panel uses industrial wastes to reduce the manufacturing cost, material cost, disposal problems and mainly environmental pollution issues raised by industrial wastes. The carbon fiber reinforced polymer composite for the automotive roof panel comprises an epoxy resin, a modifier, a curing agent and one or more carbon fibers.

[0016] In one embodiment herein, the modifier is an industrial waste that includes carbon fiber powder. The modifier is taken in an amount of 5 weight % for fabricating the automotive roof panel as it exhibits a bending stiffness of 20 N/mm as per the ASTM standards. In one embodiment herein, the curing agent is a hardener that includes hardener hy951. In one embodiment herein, the one or more carbon fibers are selected from the list of woven fabric, knitted fabric, braid fabric, unidirectional sheet and fabric of multi-axial sheet.

[0017] According to an aspect, the invention provides a method for fabricating the automotive roof panel using the carbon fiber-reinforced polymer composite. First, at one step, 0 to 10 weight % of the modifier is mixed in the epoxy resin to acquire a mixed solution. At another step, the curing agent is added to the mixed solution so as to obtain an epoxy solution. At another step, the epoxy solution is coated on the one or more carbon fibers through a hand layup process to obtain one or more carbon epoxy fibers. Further, at another step, the one or more carbon epoxy fibers are overlaid to form the automotive roof panel through a compression moulding process.

[0018] In one embodiment herein, the one or more carbon fibers comprise two opposed surfaces and the epoxy solution is coated on both surfaces of the one or more carbon fibers. In one embodiment herein, the hand layup process is followed by a vacuum bagging process for the preparation of flat carbon fiber reinforced polymer composite slabs to know the mechanical properties as per ASTM standards. In one embodiment herein, the hand layup process is followed by the compression moulding process to acquire a desired shape and curvature of the automotive roof panel.

[0019] Further, objects and advantages of the present invention will be apparent from a study of the following portion of the specification, the claims, and the attached drawings.
Detailed description of drawings:
[0020] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate an embodiment of the invention, and, together with the description, explain the principles of the invention.

[0021] FIG. 1 illustrates a systematic procedure to fabricate a flat carbon fiber reinforced polymer composite slab using a hand layup process followed by a vacuum bagging process, in accordance with an exemplary embodiment of the invention.

[0022] FIG. 2 illustrates a systematic procedure to fabricate the automotive roof panel using the carbon fiber reinforced polymer composite by the hand layup process followed by the compression moulding process, in accordance with an exemplary embodiment of the invention.

[0023] FIG. 3 illustrates an exemplary view of surface quality of a carbon fiber reinforced polymer composite for an automotive roof panel, in accordance with an exemplary embodiment of the invention.

[0024] FIG. 4 illustrates a flowchart of a method for fabricating the automotive roof panel using carbon fiber-reinforced polymer composite, in accordance with an exemplary embodiment of the invention.
Detailed invention disclosure:
[0025] Various embodiments of the present invention will be described in reference to the accompanying drawings. Wherever possible, same or similar reference numerals are used in the drawings and the description to refer to the same or like parts or steps.

[0026] The present disclosure has been made with a view towards solving the problem with the prior art described above, and it is an object of the present invention to fabricate an automotive roof panel using carbon fiber reinforced polymer composite with carbon fiber powder to reduce weight of the roof panel and provide bending stiffness and impact strength.

[0027] In one embodiment herein, the lightweight automotive roof panel 101 is developed in place of heavy-weight roof panels by using polymer-based composites instead of conventional materials. In one embodiment herein, the carbon-fiber-reinforced polymer composite 100 for an automotive roof panel 101 uses industrial wastes to reduce the manufacturing cost, material cost, disposal problems and mainly environmental pollution issues raised by industrial wastes. In one embodiment herein, the carbon-fiber-reinforced polymer (CFRP) is a strong and lightweight material that is used to make composites for a variety of applications including aviation, transportation, and machinery. To guarantee driver safety during a rollover, automotive roof panels made of CFRP may have sufficient strength and bending stiffness.

[0028] According to an exemplary embodiment of the invention, FIG.1 illustrates a systematic procedure to fabricate a flat CFRP composite slab 103 using a hand layup process 114 followed by a vacuum bagging process 120. In one embodiment herein, the CFRP composite 100 for the automotive roof panel 101 comprises an epoxy resin 102, a modifier 104, a curing agent 106 and one or more carbon fibers 108. In one embodiment herein, the bending stiffness of automotive roof panels 101 built using CFRP composites 100 is predicted using finite element (FE) analysis to reduce production time and cost. It is observed that a 2.0 mm thickness of the CFRP composite 100 is required to produce the desired bending stiffness of 20 N/mm through FE analysis.

[0029] In one embodiment herein, the systematic procedure to fabricate the flat CFRP composite slab 103 with the obtained raw materials is as followed. Experimentally the required thickness of 2.0 mm is achieved by taking one or more carbon fibers 108 along with the addition of industrial waste as the modifier 104 i.e., carbon fiber powder at 0 weight %, 2.5 weight %, 5 weight %, 7.5 weight % and 10 weight % in the epoxy resin 102 to obtain carbon epoxy fibers 116. In one embodiment herein, the curing agent 106 is added to the mixed solution 110 of the epoxy resin 102 and the modifier 104. Later, the carbon epoxy fibers 116 are overlaid to obtain the flat CFRP composite slab 103 through the vacuum bagging process 120.

[0030] In one embodiment herein, after the successful fabrication of the flat composite slab 103, it is tested for its mechanical characterization. As per ASTM Standards, the mechanical qualities of CFRP composite slab 103 are generally determined by performing tests on the flat CFRP composite slab 103 made using the hand layup process 114, which is followed by the vacuum bagging process 120. In one embodiment herein, the mechanical characterization of the composites at 5 compositions is done as per the ASTM Standards like ASTM D638-III, ASTM-D 790 and ASTM D256 for tensile strength properties, flexural or bending strength and impact strength properties respectively. Later, the best suitable composite with respect to mechanical characteristics and that composition is used to prepare the automotive roof sheet by wet layup process followed by compression moulding to get the desired curvature for roof sheet using die arrangement.

[0031] According to an exemplary embodiment of the invention, FIG.2 illustrates a systematic procedure to fabricate the automotive roof panel 101 using the CFRP composite 100 by the hand layup process 114 followed by the compression moulding process 118. In one embodiment herein, it is observed from the results that the flexural strength is maximum for the composite filled with 5 weight % of the modifier 104 i.e., the carbon fiber powder. So, the composition with 5 weight % of the modifier 104 is selected to fabricate the automotive roof panel 101 through the compression moulding process 118.

[0032] In one embodiment herein, the systematic procedure to fabricate the automotive roof panel 101 using the CFRP composite 100 with the obtained raw materials is as followed. First, 5-weight % of the modifier 104 is mixed in the epoxy resin 102 to acquire a mixed solution 110. Later, the curing agent 106 is added to the mixed solution 110 so as to obtain an epoxy solution 112. Later, the epoxy solution 112 is coated on carbon fibers 108 through the hand layup process 114 to obtain carbon epoxy fibers 116. In one embodiment herein, the carbon fibers 108 are cut into 1800 mm 1200 mm rectangle shapes from a woven roving carbon fiber type of 50 weight %.

[0033] In one embodiment herein, the carbon epoxy fibers 108 are placed on a lower die of a compressing moulding machine. In one embodiment herein, the lower die may be in a desired shape of the automotive roof panel. In order to prevent the carbon epoxy fibers 116 from being stuck to the die, a high-temperature liquid release agent is spread to the upper and lower die surfaces. The carbon epoxy fibers 116 are heated at 60°C to soften the epoxy resin 102 and the modifier 104 i.e., the carbon fiber powder mixture, increasing their formability.

[0034] In one embodiment herein, the temperature of the carbon epoxy fibers 108 is maintained at 80°C for a few minutes to ensure that the mixed solution 110 of the epoxy resin 102 and the modifier 104 i.e., the carbon fiber powder flowed uniformly during compression moulding within the dies. Later, after undergoing curing for 90 minutes at 130°C, the curing temperature of epoxy resin 102, a cooling process is conducted. In one embodiment herein, the temperature variation at the die surface is maintained at less than 5°C.

[0035] In one embodiment herein, the fabrication of the automotive roof panel 101 using the carbon fiber reinforced polymer composite 100 is completed. Later, the automotive roof panel 101 is taken from the compression moulding machine after it is dried at a temperature that is lower than 80°C. In one embodiment herein, the fabricated automotive roof panel 101 is tested again for its bending stiffness.

[0036] According to an exemplary embodiment of the invention, FIG. 3 illustrates an exemplary view of surface quality of the carbon fiber reinforced polymer composite for the automotive roof panel. In one embodiment herein, the carbon fiber reinforced polymer composite has 5 regions to identify the surface quality of the carbon fiber reinforced polymer composite for the automotive roof panel. Region 1 and region 2 are defected regions with unfilled resin. Region 3, region 4 and region 5 are normal regions with no defects.

[0037] According to an exemplary embodiment of the invention, FIG.4 illustrates a method for fabricating the automotive roof panel 101 using carbon fiber-reinforced polymer composite 100. First, at step 402, 5-weight % of the modifier 104 is mixed in the epoxy resin 102 to acquire the mixed solution 110. At step 404, the curing agent 106 is added to the mixed solution 110 so as to obtain an epoxy solution 112. At step 406, the epoxy solution 112 is coated on the one or more carbon fibers 108 through the hand layup process 114 to obtain one or more carbon epoxy fibers 116. Further, at step 408, the one or more carbon epoxy fibers 116 are overlaid to form the automotive roof panel 101 through the compression moulding process 118.

[0038] In one embodiment herein, the carbon fibers 108 comprise two opposed surfaces and the epoxy solution 112 is coated on both surfaces of the carbon fibers 108. In one embodiment herein, the hand layup process 114 is followed by the vacuum bagging process 120 for the preparation of flat carbon fiber reinforced polymer composite slabs 103 to know the mechanical properties as per ASTM standards. In one embodiment herein, the hand layup process 114 is followed by the compression moulding process 118 to acquire a desired shape and curvature of the automotive roof panel 101.

[0039] Numerous advantages of the present disclosure may be apparent from the discussion above. In accordance with the present disclosure, the fabrication cost of the composite is reduced by the utilization of the industrial waste as the modifier 104 i.e., carbon fiber powder with the reduction in usage of carbon fiber mat and amount of epoxy resin 102. Environmental pollution and disposal problems arising from carbon fiber powder can be reduced to some extent with its usage in CFRP composite 100 manufacturing.

[0040] The lightweight automotive roof panel 101 is developed in place of heavy-weight roof panels by using polymer-based composites instead of conventional materials. The proposed carbon-fiber-reinforced polymer composite 100 for the automotive roof panel 101 uses industrial wastes to reduce the manufacturing cost, material cost, disposal problems and mainly environmental pollution issues raised by industrial wastes.

[0041] It will readily be apparent that numerous modifications and alterations can be made to the processes described in the foregoing examples without departing from the principles underlying the invention, and all such modifications and alterations are intended to be embraced by this application.

, Claims:CLAIMS:
I/We Claim:
1. A carbon fiber reinforced polymer composite (100) for fabricating an automotive roof panel (101), comprising:
an epoxy resin (102);
a modifier (104);
a curing agent (106); and
one or more carbon fibers (108).
2. The carbon fiber reinforced polymer composite (100) as claimed in claim 1, wherein the modifier (104) is an industrial waste that includes carbon fiber powder.
3. The carbon fiber reinforced polymer composite (100) as claimed in claim 1, wherein the modifier (104) is taken in an amount of 5 weight percentage for fabricating the automotive roof panel (101) as it exhibits a bending stiffness of 20 N/mm as per the ASTM standards.
4. The carbon fiber reinforced polymer composite (100) as claimed in claim 1, wherein the curing agent (106) is a hardener that includes hardener hy951.
5. The carbon fiber reinforced polymer composite (100) as claimed in claim 1, wherein the one or more carbon fibers (108) are selected from the list include woven fabric, knitted fabric, braid fabric, unidirectional sheet and fabric of multi-axial sheet.
6. A method for fabricating an automotive roof panel (101) using a carbon fiber-reinforced polymer composite (100), comprising:
mixing 0 to 10 weight % of a modifier (104) in an epoxy resin (102) to acquire a mixed solution (110);
adding a curing agent (106) to the mixed solution (110) so as to obtain an epoxy solution (112);
coating the epoxy solution (112) on one or more carbon fibers (108) through a hand layup process (114) to obtain one or more carbon epoxy fibers (116); and
overlaying the one or more carbon epoxy fibers (116) to form the carbon fiber-reinforced polymer composite (100) for fabricating the automotive roof panel (101) through a compression moulding process (118).
7. The method as claimed in claim 6, wherein the one or more carbon fibers (108) comprises two opposed surfaces and the epoxy solution (112) is coated on both surfaces of the one or more carbon fibers (108).
8. The method as claimed in claim 6, wherein the hand layup process (114) is followed by a vacuum bagging process (120) for the preparation of a flat carbon fiber reinforced polymer composite slab (103) to check mechanical properties of the flat carbon fiber reinforced polymer composite slab (103) as per ASTM standards.
9. The method as claimed in claim 6, wherein the hand layup process (114) is followed by the compression moulding process (118) to acquire a desired shape and curvature of the automotive roof panel (101).