【摘要】 对K465和K492合金进行室温拉伸、高周疲劳和差热分析实验,使用扫描电镜和透射电镜观察和分析铸态K465和K492合金中初生碳化物的形态、类型及分布。研究铸态K465和K492合金中初生碳化物对合金强度的影响。结果表明,在K465合金中形成MC型初生碳化物,呈骨架状,对合金室温强度有利;在K492合金中也形成MC型初生碳化物,当碳化物呈尺寸较大的块状时,降低合金的高周疲劳强度;为弥散分布的细小颗粒时,提高合金的高周疲劳强度。更多还原

【Abstract】 Tensile tests, high cycles fatigue tests and DSC analyses were carried out for K465 and K492 alloy. The morphology, distribution and type of primary carbide were investigated by SEM and TEM. Results show that MC-type carbide is formed as Chinese script morphology in K465 alloy. The tensile strength of as-cast K465 alloy is improved because of strengthening of Chinese script MC-type carbide. Primary MC-type carbide is also produced in as-cast K492 alloy. High-cycle fatigue strength of as-cast K492 alloy is decreased when carbide becomes blocky with the large size, while it is improved when carbide is dispersed and fine particles.更多还原