| 摘要 |
Zr(1-x)XxW2O8 in which x represents a substituent element for zirconium Zr, and 0<=x<<1, having negative thermal expansion coefficient synthesized previously is heated and melted, or a starting material formed by mixing 2 mols of tungsten trioxide WO3 and 1 mol of the sum of zirconium oxide ZrO2 and a substituent element X in accordance with a substitution amount x at a stoichiometrical ratio and then quenching the same by being placed in a casting mold of an arbitrary shape and annealing the obtained castings by being heated at 120 to 500° C., whereby negative-thermal-expansion ceramics can be molded to arbitrary size and shape without press molding the starting powder and with no formation of voids and crackings in the inside.
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