METHOD AND APPARATUS FOR FORMING AMALGAM PREFORM

摘要

A method and apparatus for forming a solid preform body of an amalgam from a thin layer of the amalgam comprises a base plate on which the amalgam in liquid form is spread into a thin layer. The amalgam comprises a mixture of a liquid metal and a powdered metal. A first temperature is applied to the amalgam layer through the base plate. The first temperature may be lower than the melting temperature of the liquid metal in the amalgam to form a frozen solid layer of the amalgam, or may be above the melting temperature of the liquid metal to maintain the amalgam layer in liquid form. A second temperature is applied to a portion of the amalgam layer which is to form the preform body. If the first temperature is below the melting temperature of the liquid metal, the second temperature is above the melting temperature of the liquid metal to form a molten zone in the amalgam layer along the edge of the preform body so as to permit the body to be separated from the remaining portion of the amalgam layer. If the first temperature is above the melting temperature of the liquid metal, the second temperature is below the melting temperature so as to form a frozen solid portion in the amalgam layer which can be removed from the amalgam layer.