Composites FAQ's
Q. What is a composite?
A. A Composite is a combination of two or more materials yielding properties superior to the individual ingredients. One material is in the form of a particulate or fiber (called the reinforcement or discrete phase). The other is formable solid (called the matrix or continuous phase). The region where the reinforcement and the matrix meet is called the interface. Composite properties are determined by chemical mechanical interaction at the interface as well as the properties of the combined materials. Fiber glass reinforced plastic (FRP or GRP) combines fiber glass (the reinforcement) with thermoplastic or thermosetting resins (the matrix).
Q. What are the advantages of composite?
A. While materials like metal are strong, this strength is equal in all directions. The advantage of composites is that strength characteristics can be custom tailored in a specific direction. Placing more material where needed and less where it is not, is one of the major advantages of composites over other materials.
Q. How do we design with FRP?
A. The variation in design options, resins and reinforcement selection, and molding process that give composite materials an advantage over other materials can also make working with them a bit more complicated, especially when one needs to maximize the quality and reduce costs. The key is to match the correct variables with the application.
Q. Where are the majority of Composites used today?
A. Fiberglass Composites are used in virtually every major industry worldwide, being too numerous to identify. Some of the most visible would be Heavy Transportation, Agriculture, seating, bathware, communications,military, aerospace and wind energy.
Q. What types of reinforcements are available?
A. Fiberglass represents the overwhelming majority. There are also aramids, carbon, UHMWPE, crystalline PP, basalt, steel and a variety of natural fibers.
• Glass fibers come in a variety of grades and sizes, but all rely upon the inherent strength of highly pure engineered strands to provide an economical reinforcement to the most prevalent composite, fiberglass.
• Carbon fibers also come in a variety of grades and sizes, and were once limited to the aerospace industry due to their high cost. Carbon fiber imparts significantly more stiffness to a composite than glass fibers, at a lower weight, and as the cost of the fibers have decreased, the utilization of carbon fibers have made their way into other industries.
• Aramid fibers, recognized more commonly by their trade names of Kevlar and Twaron, are very strong, lightweight, and heat resistant fibers. Aramid fibers are most commonly used in high-end composites that require optimal strength-to-weight performance.
• Thermoplastic fibers are strands of thermoplastic resin, from polypropylene to ultra-high molecular weight polyethylene, that are lightweight, chemical resistant, and very tough.
• Natural Fibers have been in "composites" for thousands of years, dating back to the use of straw in mud bricks for primitive buildings. In more recent times, with a focus on renewable resources, there has been increased use of natural fibers in composites, focused mostly in thermoplastic composites. As with any natural resource there is natural variation in material and performance, variation that has thus far been too great for many composite manufacturing processes. As agri-tech and manufacturing process continue to evolve and expand with a focus on such.
• Fabrics are produced from all of the above fibers in a multitude of weaves. These fabrics, from unidirectional to three-dimensional weaves, are all designed and engineered to optimize particular mechanical properties in specific directions within the composite.
• Cores are materials that have been encapsulated within a composite laminate, typically designed to increase the stiffness or increase the insulative properties of the composite, without significantly increasing the weight of the system. The use of cores are even used to "tune" a composite's transparency to specific electromagnetic radiation (i.e. various radar bands). Examples of core material include a wide range of materials, from polyurethane foam to thermoplastic or even aluminum honeycomb structures.
Q. How does the cost of Composite moldings compare to other materials?
A. The cost of a part depends on many factors like how many are made, how expensive the tooling is, the cost of design, testing and fabrication, shipping costs, insurances, and so forth. The cost of using a part includes its impact on the environment, how long it will last, how it recycles, how much maintenance is necessary and much more. Composites constituent materials are more expensive than common materials like steel and wood but often a composite product has the lowest total lifecycle cost.
Q. How much and what kind of design assistance do you offer?
A. The MFG Design Center can provide various levels of design assistance. We assist customers by providing cost effective designs or changes to existing designs for composites manufacturability. This design assistance is communicated through MFG Cad developed (CATIA) 3D Models and reviewed via online meetings, including evaluating customer Cad design proposals. MFG develops complex 3D design models from initial concept through production release for tooling. Various cases when timing is critical and Customer’s Engineers & Designers are not familiar with design for composites MFG provides 3D designs for customers for their review and final approval. Additionally MFG provides online DFMA (Design For Manufacture & Assemble) education and develops composite design proposals that replace exiting metal structures, MFG proposals consolidate parts, reduce weight & cost.
Design Costs are evaluated on a project basis. MFG provides a certain level of value add on projects awarded to MFG. Design rates range from $85-$125 should we include a range?
We offer help regarding practicality and economic feasibility, design for manufacturability, packaging, assembly methods, tolerances and fit, structural engineering, materials suitability, etc.
Q. What are the advantages of designing in composites, over other materials?
A. Corrosion Resistant, High Strength to lightweight ratio, Dimensional Stability, Parts Consolidation and Tooling investment, High Dielectric Strength & Low Moisture Absorption, Minimum Finishing Required, Design Flexibility.
Low tooling costs, parts consolidation, low lifecycle cost, great strength to weight ratio, high dimensional repeatability.
Q. How do composites compare with other materials?
A.
See above and download the Techniqes & Technologies for Effectiveness manual.
Q. How do you choose and recommend various molding processes for my design?
A. Volume of parts required, expected lifetime of current design features , tool budget and part cost are all determining factors in the choice of process. Part design can benefit and be greatly enhanced by early tooling discussions . The correct tool choice will influence the rate of molding and therefore, cost.
Q. What are the environmental (green) advantages of fiberglass composite moldings?
A. Fiberglass composite moldings are widely approved and accepted for use in environmental applications such as Water Treatment facilities, air quality control equipment and alternative energy production sites such as wind and solar energy systems.
The manufacturing process of these products is technologically advanced, meeting stringent air quality standards as established by federal and state agencies.
Q. Do you have a materials research laboratory?
A. Yes, it is certified to ISO 17025 and GL standards, consists of chemists, polymer and chemical engineers, has significant process mimic and materials characterization resources.
Q. What are your most recent material/technical advances?
A. Nano enhanced liquid composite moldings, nano SMC for Pontiac Solstice, LCM using reinforcing fibers from natural and post industrial sources. HAWK and PRIME initiatives dvds are available upon request.