What Is The Difference Between FRP And GRP?
GRP: Fiberglass Reinforce plastic, also known as FRP, Chinese name: Glass-reinforced thermosetting plastic or glass fiber reinforced plastic.
It is a composite material, including the matrix and the reinforcement of two parts. The matrix of GRP material is resin, which plays the role of bonding, accounting for 30% -40% of the total volume. Resin is a thermosetting plastic, including epoxy (EP), phenolic (PF), etc., while the resin is also organic non-metallic material. GRP material reinforcement is glass fiber, plays a role in strengthening. Glass fiber is a kind of inorganic and nonmetal artificial inorganic fiber, such as glass fiber, carbon fiber, Kevlar fiber B, etc., accounting for 60% ~ 70% of the total volume. Therefore, GRP is an organic non-metallic and inorganic non-metallic composite plastic matrix composites.
GRP has good electrical insulation properties and bonding properties, high mechanical strength and heat resistance, textiles, resistance to acid and alkali and organic solvents, and mold-resistant bacteria. Molding shrinkage is small, the volume shrinkage of 1% to 5%, after adding curing agent to be pressurized heating molding, can also be cured at room temperature contact pressure.
FRP (Fiber Reinforced Plastics) fiber-reinforced plastics, generally refer to glass fiber reinforced unsaturated polyester, epoxy resin and phenolic resin matrix, commonly known as glass steel.
1,What is FRP?
FRP is a plastic, glass fiber reinforced plastic, available in English letters FRP said. Plastic, literally, refers to the plasticity of the material, now generally refers to the artificial plastic, that is made of resin plus various additives, if the resin does not add any additives can not be called plastic, can only be called resin. Due to the thermoplastic resin and thermosetting of the points, the plastic is also divided into two types thermoplastic and thermosetting. If glass fibers are used to reinforce thermoplastics, they can be called thermoplastic FRP: thermosetting FRP, if glass fiber reinforced thermosetting plastics, is used. The current production of FRP mainly refers to the thermosetting terms. FRP is a composite material if it is used from a material point of view, and FRP can be considered as a structure from its own composite structure.
2, FRP what are the characteristics and deficiencies?
A: FRP has the following characteristics.
(1) light and strong
Relative density of 1.5 to 2.0, only the carbon steel 1/4 ~ 1/5, but the tensile strength is close to, or even more than carbon steel, and the specific strength can be compared with the advanced alloy steel. Therefore, it has excellent results in the applications of aviation, rockets, space vehicles, high-pressure vessels and other products requiring weight reduction. Some epoxy FRP tensile, bending and compressive strength can reach more than 400Mpa. Note Specific strength, ie strength divided by density.
(2) good corrosion resistance
FRP is a good corrosion-resistant material that has good resistance to the atmosphere, water, and acids, alkalis, salts, oils and solvents in general concentrations. Has been applied to all aspects of chemical preservation, and is replacing carbon steel, stainless steel, wood, and non-ferrous metals.
(3) good electrical properties
Is an excellent insulating material used to make insulators? High frequency can still protect the good dielectric. Microwave permeability is good and has been widely used in radar radome.
(4) good thermal performance
FRP has a low thermal conductivity of 1.25 to 1.67 kJ / (m · h · K) at room temperature, and only 1/100 to 1/1000 of the metal, which is an excellent thermal insulator. Ideal for thermal protection and ablation materials at transient ultra-high temperatures, it protects the spacecraft from erosion of high-velocity airflow above 2000 ° C.
(5) design is good
① According to the need for the flexibility to design a variety of structural products to meet the requirements can make the product has very good integrity.
② can fully select the material to meet the performance of the product, such as you can design a decay-resistant, instantaneous high temperature, the product has a special high strength in one direction, good dielectric properties, and so on.
(6) Good workmanship
① According to product shape, technical requirements, use and quantity to flexibly choose the molding process.
② simple process can be a molding, economic results are outstanding, especially for complex shapes, not easy to shape a small number of products, but also highlight its superiority of the process.
Can not ask for an FRP to meet all the requirements, FRP is not a panacea, FRP also has some shortcomings.
Low modulus of elasticity
FRP has a modulus of elasticity twice that of wood but is ten times smaller than that of steel (E = 2.1 x 106), so it is often underestimated and easily deformed in the product structure.
