论文部分内容阅读
采用大塑性变形法制备氧化物弥散强化铂铑(Pt5RhODS)复合材料,对材料进行了高温蠕变试验。结果表明,复合材料在高温低应力条件下,表现出的名义应力指数随温度变化较小,名义激活能高于纯Pt和Pt10Rh合金,而且比常规合金材料具有更好的高温蠕变性能。复合材料的高温蠕变性能用晶界反应控制来解释,说明复合材料的蠕变受到扩散蠕变机制控制。复合材料的蠕变断裂行为符合连续蠕变损伤中的内截面损伤模型,蠕变断裂特征为沿晶断裂。
A large amount of plastic deformation method was used to prepare the oxide dispersion strengthened platinum-rhodium (Pt5RhODS) composites, and the materials were subjected to high-temperature creep test. The results show that the nominal stress exponent changes little with temperature under high temperature and low stress, and the nominal activation energy is higher than that of pure Pt and Pt10Rh alloys, and has better high temperature creep properties than the conventional alloy materials. The high-temperature creep properties of the composites are explained by the grain boundary reaction control, indicating that the creep of the composites is controlled by the diffusion creep mechanism. The creep rupture behavior of the composites conforms to the model of internal cross-section damage in continuous creep damage, which is characterized by intergranular fracture.