| 摘要 |
A system is disclosed for casting rollers having an external cylindrical surface defined by firmly-held carbide particles. As disclosed, a cylindrical mold is revolved about a central horizontal axis and heavy, tungsten-carbide particles are released within the mold to accumulate as a layer on the internal cylindrical surface of the mold. Molten metal of specific characteristics is injected into the mold; being lighter does not displace the particles at the mold surface yet forces and characteristics are such that the metal wets the particles and fills the interstices therebetween to provide an effective matrix upon solidification. Heat treatment overcomes the problem attendant the inherent rapid cooling, after which the metal may be machined. Requisite characteristics of the metal for the disclosed process include: dimensional stability, high compressive yield strength, high shock and impact resistance, and good casting characteristics as high fluidity and low surface tension to "wet" the tungsten-carbide particles.
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