摘要 |
Improved resin-bonded powdered metal components are protected against corrosion and reduction of crush strength during contact with corrosive fluids such as alcohols, ethanol-containing fuels, glycols and peroxide-containing fuels by a resin system coating that, when cured, provides a relatively high crosslink density and relatively few hydrolysable radicals. Magnetic properties of resin-bonded powdered metal magnets are protected from heat degradation by the cured resin coating. The coating can be a heat-cured resin system comprising a phenol novolac resin and a compatible hardener. In one embodiment magnetizable powdered materials have an uncured resin system coating to provide a B-stage material that can be cured after compression shaping.
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