VICOTE F808 Natural Aqueous Dispersions for Use on Ferrous and Non-Ferrous Metals
VICOTE is the brand name for the Victrex range of coatings. VICOTE Coatings are available through Victrex or its preferred coater network.
The VICOTE F808 natural grades have been specifically formulated to provide a resilient coating with high wear and abrasion resistance combined with excellent release properties on ferrous substrates such as carbon and cast steels. These properties are retained at high temperatures where other release coatings would potentially fail. VICOTE dispersions have a low level of extractables. Contact Victrex for further details.
VICOTE F808 Natural Dispersions
VICOTE F808 natural dispersions are aqueous based however there are small amounts of solvents present. Refer to the appropriate MSDS sheet for details.
The VICTREX™ PEEK polymer contained in the VICOTE dispersions like other non-coating grades of VICTREX PEEK polymer are thermoplastic in nature and exhibit flow above the melt temperature. When processed using the correct guidelines the coatings will exhibit the excellent properties that VICTREX PEEK polymer is renowned for.
VICOTE products have excellent chemical resistance. Consult the Victrex Chemical Resistance Data brochure for further details.
SUBSTRATES AND PREPARATION
VICOTE F808 can be applied to most ferrous and non-ferrous substrates. A primer is not required. Cast metals need to be de-gassed in an oven to prevent pin holes in the coating surface. Substrates should be free from grease, oils and corrosion prior to coating. Solvent de-greasing and grit blasting with aluminium oxide with final solvent wash should ensure a suitable surface for coating. Note: Phosphate pre-treated substrates are not recommended for VICOTE Coatings grades as the high processing temperatures required for processing can result in de-lamination of the coating.
SPRAYING
A conventional gravity fed spray gun with a nozzle size between 0.7 and 1.0mm has been found suitable for applying VICOTE dispersions. Edges of components should be sprayed first before applying a complete coating. An air pressure to the gun of between 35 and 50 psi has been found to be a suitable spray pressure. Spray at right angles to the substrate wherever possible. The spray gun and cup can be cleaned with water after use.
PROCESSING
For general processing information consult the VICOTE dispersion coating guides. Coated parts should be dried in air for 5 minutes then dried in an oven for 5 minutes at 120°C before placing in an oven at 400°C to melt and fuse the coating.
By following the processing guide smooth coatings should be achievable. Because VICOTE materials are semi crystalline thermoplastics, as with all these types of products shrinkage will take place when the coating cools. Depending on the mass of the substrate, coating thickness and rate of cooling will determine the amount of shrinkage.
Normally processed and cooled coatings should result in crystalline coatings which should not require further post processing treatment. However, an increase in crystallinity may enhance certain properties such as wear and scratch resistance. To anneal the coating the part should be placed in an air circulating oven and the temperature raised at 10°C per minute to 250°C and held at that temperature for 30 minutes to 1 hour.
With coated parts that are subject to a high service temperature it may be beneficial to anneal the parts at 10°C above the maximum service temperature to prevent further volume change of the coating. Note: The colour of the final coating when using VICOTE F808 natural may depend on the substrate. For example VICOTE processing temperatures will turn some steels blue and may impart a blue/grey colour to the final VICOTE Coating.
STORAGE AND HANDLING CONSIDERATIONS
VICOTE drums should be stored in a clean dry environment and should not be stored with the lids removed as this may result in airborne dust contaminating the product, which could cause coating defects.
The VICOTE dispersions will soft settle after prolonged standing. They can be re- dispersed readily by stirring of the liquid suspension. The drums can also be rolled and re-disperse to ensure homogeneity. High shear dispersing should be avoided as the wetting agent is prone to shear thinning. It is recommended that the dispersions are not allowed to freeze. Optimum storage temperature is 5°C – 25°C.
VICOTE F808 natural is packed in 20 kg polythene UN drums enclosed in a strong cardboard box with the VICOTE logo.
SAFETY PRECAUTIONS
Before applying VICOTE dispersions, read the appropriate Material Safety Data Sheet (MSDS) and the Processing Guide, available from Victrex.
VICOTE F808 natural resins contain fluoropolymers which must only be applied where Local Extract Ventilation (LEV) is available with the gasses removed completely from the work area. The hot gasses given off during melt processing can cause flu like symptoms. Care should be taken not to inhale such gasses; also contact of the polymer with tobacco products should be avoided. Washing of hands and good housekeeping are a prerequisite before and after handling these products.
