BMC is manufactured by mixing strands (Greater than 1/8” and less than 2"[2][3]) of chopped glass fibers, styrene, an initiator, and filler in a mixer with an unsaturated thermoset resin (commonly polyester resin, vinyl ester resin or epoxy resin). The mixing is done at room temperature and stored at low temperatures to slow down curing prior to molding. The concentration of the mixture can vary depending on application, but is typically 30% glass fibers, 25% filler, and 45% resin, styrene, and initiator.[2] The material is provided in bulk or in logs approximately 4" in diameter.[2][3] The glass fibers in BMC increase the strength properties of the product to be higher than standard thermoplastic products.
The viscosity of BMC dictates how effectively it can fill a mold. When at high viscosity, the pressure applied to the BMC is not enough for it to flow, and when at low viscosity, the fibers will stay in one place while the rest of the material flows without them. The viscosity constrains the amount of each component that can be used when mixing BMC. Having a large amount of fibers or longer fibers improves mechanical properties but makes the BMC more viscous. Adding fillers can lower the cost of the BMC or improve a certain property, but causes the BMC to become more viscous. Adding more styrene lowers viscosity but causes the moulded BMC to become brittle. When at an optimal viscosity to allow flow, components made using BMC can be up to 16" in their longest dimension before the components of the mixture begin to separate.[2]
^ abIndustrial minerals and their uses : a handbook and formulary. Ciullo, Peter A., 1954-. Westwood, N.J.: Noyes Publications. 1996. ISBN1591241944. OCLC 49708409.{{cite book}}: CS1 maint: others (link)
^ abcdBrent., Strong, A. (2008). Fundamentals of composites manufacturing : materials, methods and applications (2nd ed.). Dearborn, Mich.: Society of Manufacturing Engineers. ISBN9781613449677. OCLC 799881324.{{cite book}}: CS1 maint: multiple names: authors list (link)
^ abV., Rosato, Dominick (2003). Plastics engineered product design. Rosato, Donald V. Oxford: Elsevier Advanced Technology. ISBN9780080514079. OCLC 162130578.{{cite book}}: CS1 maint: multiple names: authors list (link)
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bulk, moulding, compound, bulk, moulding, composite, dough, moulding, compound, ready, mold, glass, fiber, reinforced, thermoset, polymer, material, primarily, used, compression, moulding, well, injection, moulding, transfer, moulding, typical, applications, i. Bulk moulding compound BMC bulk moulding composite or dough moulding compound DMC 1 is a ready to mold glass fiber reinforced thermoset polymer material primarily used in compression moulding as well as in injection moulding and transfer moulding 1 Typical applications include demanding electrical applications corrosion resistant needs appliance automotive and transit Manufacturing editBMC is manufactured by mixing strands Greater than 1 8 and less than 2 2 3 of chopped glass fibers styrene an initiator and filler in a mixer with an unsaturated thermoset resin commonly polyester resin vinyl ester resin or epoxy resin The mixing is done at room temperature and stored at low temperatures to slow down curing prior to molding The concentration of the mixture can vary depending on application but is typically 30 glass fibers 25 filler and 45 resin styrene and initiator 2 The material is provided in bulk or in logs approximately 4 in diameter 2 3 The glass fibers in BMC increase the strength properties of the product to be higher than standard thermoplastic products The viscosity of BMC dictates how effectively it can fill a mold When at high viscosity the pressure applied to the BMC is not enough for it to flow and when at low viscosity the fibers will stay in one place while the rest of the material flows without them The viscosity constrains the amount of each component that can be used when mixing BMC Having a large amount of fibers or longer fibers improves mechanical properties but makes the BMC more viscous Adding fillers can lower the cost of the BMC or improve a certain property but causes the BMC to become more viscous Adding more styrene lowers viscosity but causes the moulded BMC to become brittle When at an optimal viscosity to allow flow components made using BMC can be up to 16 in their longest dimension before the components of the mixture begin to separate 2 See also editSheet moulding compound SMC Fibre reinforced plastic Thermoset polymer matrixReferences edit a b Industrial minerals and their uses a handbook and formulary Ciullo Peter A 1954 Westwood N J Noyes Publications 1996 ISBN 1591241944 OCLC 49708409 a href Template Cite book html title Template Cite book cite book a CS1 maint others link a b c d Brent Strong A 2008 Fundamentals of composites manufacturing materials methods and applications 2nd ed Dearborn Mich Society of Manufacturing Engineers ISBN 9781613449677 OCLC 799881324 a href Template Cite book html title Template Cite book cite book a CS1 maint multiple names authors list link a b V Rosato Dominick 2003 Plastics engineered product design Rosato Donald V Oxford Elsevier Advanced Technology ISBN 9780080514079 OCLC 162130578 a href Template Cite book html title Template Cite book cite book a CS1 maint multiple names authors list link nbsp This material related article is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title Bulk moulding compound amp oldid 1166125738, wikipedia, wiki, book, books, library,
