Piston with cooling cavity partially filled with thermally conductive metal-containing composition

摘要

A piston for an internal combustion engine includes a sealed cooling cavity that extends circumferentially around a central axis below the bowl rim of the upper crown. A metal-containing composition having high thermal conductivity fills a portion of the sealed cooling cavity and dissipates heat. The metal-containing composition includes a base material having a melting temperature less than 181 degrees Celsius and a plurality of metal particles having a thermal conductivity greater than that of the base material. For example, the metal-containing composition can include copper particles dispersed in silicone oil or copper particles dispersed in a mixture of alkali metals. During high temperature operation, as the piston reciprocates in the cylinder bore, the base material is a liquid that flows through the cooling cavity and dissipates heat from the upper and lower crowns.