Crclic Oxidation Behavior of W - Mo - ( 29 - 48wt% ) Cr alloys
윤국한Kook Han Yoon, 최주Ju Choi
Abstract
Effects of Cr content on the cylic oxidation behavior of W-Mo-(29-48w%)Cr alloys have been studid by measuring weight changes and observing oxide scales during an oxidation test at 1000, 1100, and 1200℃ in air. The W-Mo-Cr alloy ingots were prepared by a plasma are melting process. The oxidation resistance was found to improve as the Cr content increased but to decrease repidly as the temperature increased. The observed optimum Cr contents for oxidation resistance were more than 35% at 1000℃ and 48% at 1100℃. The W-26Mo-48Cr ally showed good oxidation resistance by forming an abherent and thin continuous layer of Cr₂O₃ at 1100℃ up to 100cycles. This is believed due to the formation of a new Cr₂O₃ healing layer laterally grown from the Cr₂O₃ layer was was damaged. However, an accelerated oxidation ocurred by first forming the porous multilayers of Cr₂O₃ and Cr₂WO_6 and then by spalling of these layers at 1200℃.