含二硫化钼镍铬基高温复合材料的高温氧化行为

Oxidation Behavior of Ni-Cr Based Powder Metallurgy Composites Containing MoS_2 at High Temperatures

采用粉末冶金方法制备了添加质量分数为6%二硫化钼的镍铬基复合材料;对其在800,900和950℃的高温氧化行为进行了研究,绘制了氧化动力学曲线;用扫描电镜对其氧化表面形貌和横截面组织进行了观察。结果表明:该镍铬基复合材料在800℃以及900℃氧化100 h后,其氧化动力学符合抛物线规律,在材料表面生成了Cr2O3和NiCr2O4氧化膜,具有一定的抗氧化性能;在950℃氧化时,表面氧化膜出现剥落。

Ni-Cr based composite material containing 6wt% MoS2 and 15wt% tungsten was prepared by powder metallurgy method. Oxidation behavior of the composite was studied in air at 800, 900 and 950 ℃ and oxidation kinetics curves were gained. The oxide morphology and mierostructure were analyzed by X-ray diffraction （XRD） and SEM. The scales formed at 800 and 900 ℃ were complicated, with a layer mainly composed of Cr2O3 and a small amount of NiCr2O4. The oxidation kinetics of the composite nearly followed the parabolic oxidation law. At 950℃, the oxide scales formed on the oxidized composite were found to be loose.