摘要 |
<p>A method of forming a refractory die (1), and a method for forming a metal article using a refractory die (1). The refractory die (1) is formed of a ceramic material by casting a slurry (14) containing particles of the ceramic material onto a mold. Then the mold is vibrated while excess liquid medium from the slurry (14) is simultaneously removed, whereby ceramic particles continue to flow into surface details of the mold. The present method of forming a refractory die minimizes drying and firing shrinkage, and even adjusts for drying and firing shrinkage by inclusion of kyanite in the refractory die. According to the method of forming a metal article, a particulate material (2) containing powdered metal is compressed on a refractory die (1) at an elevated temperature and pressure. The consolidated particulate material is differentially cooled, wherein a first, low mass portion contacting the refractory die is cooled more quickly than an opposing, high mass portion of the consolidated body. According to this method, hot tears are prevented.</p> |