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Material selection is a step in the process of designing any physical object. In the context of product design, the main goal of material selection is to minimize cost while meeting product performance goals. [1] Systematic selection of the best material for a given application begins with properties and costs of candidate materials.
The development of plastics has evolved from the use of naturally plastic materials (e.g., gums and shellac) to the use of the chemical modification of those materials (e.g., natural rubber, cellulose, collagen, and milk proteins), and finally to completely synthetic plastics (e.g., bakelite, epoxy, and PVC).
PAEK plastics are characterized by phenylene rings that are linked via oxygen bridges (ether and carbonyl groups ). The ratio and sequence of ether to ketones mainly affects the glass transition temperature and melting point of the polymer. It also affects its heat resistance and processing temperature.
Draft angle design is an important factor when designing plastic parts. Because of shrinkage of plastic material, injection molded parts have a tendency to shrink onto a core. This creates higher contact pressure on the core surface and increases friction between the core and the part, thus making ejection of the part from the mold difficult.
CAMPUS (acronym for Computer Aided Material Preselection by Uniform Standards) is a multilingual database for the properties of plastics. It is considered worldwide as a leader in regard to the level of standardization and therefore, ease of comparison, of plastics properties.
Polyetherimide (PEI; branded as Ultem [1]) is an amorphous, amber-to-transparent thermoplastic with characteristics similar to the related plastic PEEK.When comparing PEI to PEEK, the former is cheaper but has lower impact strength and a tighter temperature range.
HDPE is known for its high strength-to-density ratio. [4] The density of HDPE ranges from 930 to 970 kg/m 3. [5] Although the density of HDPE is only marginally higher than that of low-density polyethylene, HDPE has little branching, giving it stronger intermolecular forces and tensile strength (38 MPa versus 21 MPa) than LDPE. [6]
The material enters the mold through the sprue bush. Top plate—It is used to clamp the top half of the mold to the moving half of the molding machine and is usually made of mild steel. Cavity plate—The plate used to create a cavity (via a gap) that will be filled with the plastic material and form the plastic component. Usually made of mild ...