| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to impart a shape to an obtained bulk body by coating the surface of an ingot or a compacted powder comprised of only Al with Ca or a Ca-compound and then heat treating the coated material in an atmosphere containing gaseous nitrogen in order to nitride it. SOLUTION: A coated layer 2 containing Ca is formed by coating the surface of a metal Al ingot or a compacted powder 1 of Al powder with Ca or a Ca compound. Then, the metal aluminum ingot or the compacted powder 1 having the Ca-containing coated layer 2 on its surface is heat treated in an atmosphere containing gaseous nitrogen at 900 to 1,200 deg.C to form an AlN-bulk body 3 on the ingot or compacted powder 1. Though the Ca or the Ca-compound remains (Ca-containing layer 2') between the formed AlN-bulk body 3 and a porous body 1, which is formed from the Al ingot or the compacted powder 1 by supplying a portion of Al, a portion of the Ca or the Ca-compound is also present(Ca- containing layer 2") on the surface of the AlN-bulk body 3, after nitriding reaction. Heat treatment is preferably carried out in a non-oxidizing atmosphere containing gaseous nitrogen in an amount of >=1,000 ppm. |
