| 摘要 |
PURPOSE:To form a good stuck layer having durability with a method for thermally spraying a mixture composed of an easy oxidizable metal and refractory oxide by specifying the compsn. of the mixture. CONSTITUTION:The mixture composed of 5 to 25wt.% Al having >=50mu grain size, <=40% Al2O3 and 30 to 80% MgO is carried to the tip of a nozzle by gaseous CH3H8 or a gaseous mixture composed of the gaseous C3H8 and gaseous N2 and gaseous O2 is ejected at the tip of the nozzle to heat and blow the gaseous mixture by the high temp. combustion flame of the gaseous C3H8-O2. A repair layer consisting of the compsn. composed of 30 to 72% Al2O3 and 28 to 70% MgO is formed in the repair part. The heat generated by the oxidation of the Al powder is used and the conversion of the Al powder itself to the Al2O3 can be utilized in the process of the heating and spraying by this method. The fusion of the refractory particles is, therefore, facilitated and the fused stuck layer forms MgO.Al2O3 spinel. The layer having the excellent resistance to a molten steel and slag are thus obtd. |
