【摘要】 研究了 Si对 K40 S合金显微组织及 81 5℃ ,2 0 5MPa条件下的力学性能的影响。结果表明 ,随着 Si含量的升高 ,K40 S合金凝固时界面生长由枝晶生长转向明显的内生生长 ;虽然 Si元素主要在枝晶间或晶界偏析 ,但当 Si含量升高到一定程度后 ,枝晶内的浓度逐渐升高而达到显著水平 ;持久拉伸断口呈现明显的枝晶间断裂特征 ,持久寿命下降。更多还原

【Abstract】 WT5BZ]The effect of Si on the microstructure and the stress rupture property at 815℃/205MPa of K40S superalloy was studied It is shown that, with the rise of Si addition, interface grows by way of endogeneous growth instead of dendritic interface growth during the alloy solidification ;Si can not only segregate in interdendritic or intergranular greatly, but also dissolve into the matrix noticeably; the appearance of the fracture surface of stress rupture specimens varies from transcrystalline to interdendritic,and the stress rupture life decreases更多还原