【摘要】 对两种离心铸造耐热钢蠕变持久性能进行了研究。结果发现,HP耐热钢具有较低的蠕变断裂强度和低的蠕变速度,而HP-Nb具有较高的蠕变断裂强度和高的蠕变速度,这不符合通常的蠕变速度与蠕变断裂时间之间一般相依关系。产生这种结果的原因是后者在晶界上形成了共晶碳化铌。在晶界上形成形态复杂稳定的碳化物能阻止空洞的连接,从而延长了蠕变第三阶段,增加了断裂时间。更多还原

【Abstract】 Greep rupture properties of two kinds of centrifugally cast heat-resistant steel have beeninvestigated. It is found that HP has lower creep rupture strength and low creep rate, howeverHP-Nb has higher creep rupture strength and high creep rate. It is not consistant with commonrelationship between creep rate and creep rupture time. It is attributed to eutectic carbides NbCformed at grain boundary in HP-Nb. The stable eutectic carbides with complex morphologyprevent coalescence of grain boundary voids and therefore prolong tertiary creep stage and ru-pture time.更多还原