Durable high friction coating (DHFC) for brake application
Technologies are described for a durable high friction coating (DHFC), which may be manufactured by mixing a binder, a filler, and one or more additives in liquid form, loading the liquid mixture onto a coil material (metal substrate) and curing for subsequent cutting and/or stamping. The metal substrate with cured DHFC layer(s) may be cut to shape to form brake shims. Water-based binders may be used for environmentally friendly chemicals. In some examples, the binder(s) in the DHFC may be in a range from at least 70 weight % to less than 95 weight % and the filler(s) in a range from at least 5 weight % to less than 30 weight % with an elastomeric polymer in a range from at least 1 weight % to less than 8 weight % and a rheology modifier in a range from at least 0.5 weight % to less than 2 weight %.
1 . A durable high friction coating (DHFC) for a brake system, the DHFC comprising:
one or more binders in a range from at least 70 weight % to less than 95 weight %, wherein the one or more binders comprise phenoxy in aqueous solution, polyurethane in aqueous solution form, melamine formaldehyde, bisphenol A epoxy, urea-formaldehyde, or a combination thereof;
one or more fillers in a range from at least 5 weight % to less than 30 weight %;
an elastomeric polymer in a range from at least 1 weight % to less than 8 weight %; and
one or more additives in a range from at least 0.5 weight % to less than 2 weight %, wherein the one or more binders, the one or more fillers, the one or more additives, and the elastomeric polymer are mixed in liquid form and are cured into a layer of DHFC.
2 . The DHFC of claim 1 , wherein the one or more fillers comprise silicon carbide, (SiC), aluminum oxide (Al 2 O 3 ), boron nitride (BN), titanium dioxide (TiO 2 ), or a combination thereof.
3 . The DHFC of claim 1 , wherein the one or more additives comprise a rheology modifier, an antifoam agent, a plasticizer, a pigment, an adhesion promoter, or a combination thereof.
4 . The DHFC of claim 1 , wherein a thickness of the layer of DHFC is in a range from about 0.020 mm to about 0.060 mm.
5 . The DHFC of claim 1 , wherein the layer of DHFC is formed on a layer of elastomer and the layer of DHFC and the layer of elastomer are cured together.
6 . The DHFC of claim 5 , wherein the layer of elastomer comprises synthetic polyisoprene, polybutadiene, chloroprene rubber, polychloroprene, neoprene, butyl rubber, halogenated butyl rubber, styrene-butadiene rubber, nitrile rubber, hydrogenated nitrile rubber, or a combination thereof.
7 . The DHFC of claim 1 , wherein the elastomeric polymer comprises synthetic polyisoprene, polybutadiene, polychloroprene, neoprene, or a combination thereof.
8 . A brake shim comprising:
a metal substrate;
a first durable high friction coating (DHFC) layer deposited on a first surface of the metal substrate; and
a second DHFC layer or an adhesive layer deposited on a second surface of the metal substrate opposite the first surface, wherein the first and second DHFC layers comprise:
one or more binders comprising phenoxy in aqueous solution, polyurethane in aqueous solution form, melamine formaldehyde, bisphenol A epoxy, urea-formaldehyde, or a combination thereof in a range from at least 70 weight % to less than 95 weight %;
one or more fillers in a range from at least 5 weight % to less than 30 weight %;
an elastomeric polymer in a range from at least 1 weight % to less than 8 weight %; and
one or more additives in a range from at least 0.5 weight % to less than 2 weight %, wherein the one or more binders, the one or more fillers, the one or more additives, and the elastomeric polymer are mixed in liquid form and are cured to form the first and second DHFC layers.
9 . The brake shim of claim 8 , wherein a thickness of the metal substrate is in a range from about 0.350 mm to about 0.400 mm, and a thickness of the first and second DHFC layers is in a range from about 0.020 mm to about 0.060 mm.
10 . The brake shim of claim 8 , wherein the metal substrate comprises stainless steel, nickel, nickel-aluminum alloy, iron-nickel-chromium-molybdenum alloy, or a combination thereof.
11 . The brake shim of claim 8 , further comprising:
an elastomer layer deposited on the first surface or the second surface prior to deposition of the first or second DHFC layers, wherein the first or second DHFC layers are deposited onto the elastomer layer.
12 . The brake shim of claim 11 , wherein the first or second DHFC layers and the elastomer layer are cured together.
13 . The brake shim of claim 8 , wherein the metal substrate and the first or second DHFC layers are cut to shape to form the brake shim.
14 . The brake shim of claim 8 , wherein the one or more fillers comprise silicon carbide, (SiC), aluminum oxide (Al 2 O 3 ), boron nitride (BN), titanium dioxide (TiO 2 ), or a combination thereof.
15 . A method to manufacture a durable high friction coating (DHFC) for a brake system, the method comprising:
mixing a binder, a filler, an elastomeric polymer, and an additive in liquid form to form a mixture, wherein the binder comprises phenoxy in aqueous solution, polyurethane in aqueous solution form, melamine formaldehyde, bisphenol A epoxy, urea-formaldehyde, or a combination thereof and is in a range from at least 70 weight % to less than 95 weight %, the filler is in a range from at least 5 weight % to less than 30 weight %, the elastomeric polymer is in a range from at least 1 weight % to less than 8 weight %, and the additive is in a range from at least 0.5 weight % to less than 2 weight % in the mixture;
loading the mixture onto a coil material to form a layer of DHFC; and
curing the layer of DHFC on the coil material through heat treatment.
16 . The method of claim 15 , wherein mixing the binder, the filler, the elastomeric polymer, and the additive in liquid form comprises:
mixing, in a water-based media, the binder; the filler selected from silicon carbide, (SiC), aluminum oxide (Al 2 O 3 ), boron nitride (BN), titanium dioxide (TiO 2 ), or a combination thereof; the elastomeric polymer; and the additive selected from a rheology modifier, an antifoam agent, a plasticizer, a pigment, an adhesion promoter, or a combination thereof.
17 . The method of claim 15 , wherein loading the mixture onto the coil material to form the layer of DHFC comprises:
loading the mixture onto the coil material using a blade; or
rolling the mixture onto the coil material using one or more rollers.
18 . The method of claim 15 , wherein curing the layer of DHFC through heat treatment comprises:
applying heated air, direct heat, or infrared heat to the layer of DHFC.