Analysing the selection method of plastics vacuum plating for aluminum and other metals and coatings
[Alcoa.com] Although plastic can replace metal in many applications, it is obviously lacking in the texture of metal. For this reason, certain methods need to be applied to coat the plastic surface with a layer of metal (aluminum, zinc, copper, silver, gold, etc.). One method is to use electroless plating and electroplating, and the other is to vacuum-sputter the metal directly on the surface of the plastic—that is, to melt the metal in a vacuum state and deposit it in the form of molecules or atoms in the plastic. A 5-10 μm metal film is formed on the surface.
The vacuum metallizing needs to be well matched with the plastic surface primer. The thickness of the primer is usually 10-20 μm. The main function is to prevent the water in the plastic, the organic solvent and the plasticizer from affecting the metal adhesion. The coating is required to have a high hardness, the primer has a plastic defect that can be modified, and can provide a smooth, flat surface to facilitate the vacuum plating performance, and adheres firmly to the plastic substrate and the plated metal. Usually used two-component normal temperature curing polyurethane and epoxy coatings, low temperature baked amino coating and thermoplastic acrylic coating.
The metal coating is easily oxidized and darkened in the air, and there are also minor vacuum defects, so it is necessary to apply a protective layer of 5-10 μm. The requirements for facing paints are: transparency, excellent water resistance, abrasion resistance, weather resistance, no operation of metallized film, and firm adhesion to metal plating. Acrylic varnish, polyester varnish, polyurethane varnish, etc. are usually used. When the primer is a thermoplastic acrylate coating, in order to prevent the topcoat solvent from eroding the primer through coating defects, a weak solvent, quick-drying topcoat can be used. Such as acrylic modified alkyd varnish, polyvinyl butyral varnish, urethane oil and so on.
The process of vacuum metallization is: plastic surface treatment (purification, activation) → priming → drying → vacuum metallization → surface coating → drying. The process flow is briefly introduced: product surface cleaning -> static electricity -> spray primer -> baking primer -> vacuum coating -> spray paint -> baking finish -> packaging .
In the entire process flow, the following points determine the success or failure of the process:
The surface condition of the part to be machined, including whether the product has defects, surface conditions, surface contaminants, etc.
The presence of surface defects can lead to a more aesthetic appearance of the appearance part. Of course, for the presence of minor defects, the spraying process can be masked. However, batch defects caused during injection molding or stamping must be removed before the incoming inspection.
The surface state, which relates to whether it is a transparent part, has a special surface roughness design. When designing the state of appearance, it is necessary to consider the overall process route before the process is formulated, otherwise it is difficult to obtain the desired appearance after completion.
Surface contaminants, for batch products, how to remove residual contaminants from previous processes is the key to quality and efficiency. For example, removal of mold release agent produced during injection molding.
The design of the fixture, including whether the fixture is adapted to the entire process flow, can ensure surface uniformity and mounting efficiency.
Link Pin is a device used for fastening/connecting objects or material together, mostly the Link Pin which QFAP supplied are applied in diggers, excavators, trucks, or railway equipments.
Most of our customers were from North America, Europe and Chinese domestic market.
Annual Production Capability: 200,000pcs
Materials: carbon steel, stainless steel, alloys steel, steel tube, etc.
Surface treatment: painting, zinc plating, blackening, passivation, nickel plating, oiled, etc.
Heat treatment: according to customer`s requirement.
QFAP have specialized in producing high precision Agriculture Parts more than 10years, Because of the long term cooperation, we could supply our customers not only the products but also our recommendation on the designs to saving costs.
Link Pin,Linking Pin Model,Link Pin Kit,Link Pin Code
SHAOXING QIFENG AUTO PARTS CO., LTD. , https://www.sxqfap.com