摘要
为探究熔体处理时间对K488合金显微组织及力学性能的影响规律,对不同时间的熔体处理[1625℃×(7~17 min)]的K488合金分别开展了900℃/270 MPa高温持久性能测试。此外,为获悉熔体处理时间影响合金持久性能的微观机制,还利用扫描电镜(SEM)和透射电镜(TEM)对持久性能测试前后的K488合金显微组织进行了系统表征。结果表明:K488合金在12 min×1625℃熔体处理条件下析出均匀、尺寸较大且立方度较高的γ′相。且相较于7 min和17 min熔体处理条件下的持久寿命,12 min×1625℃熔体处理后合金的持久寿命最高,达到204.9 h,表明12 min是K488合金的最优熔体处理时间。SEM和TEM分析认为,12 min下晶粒细化,提高晶界的强度。并且较高的γ′相尺寸和体积分数有效地抵抗了位错的切割,从而提高了K488合金的持久寿命。
In order to investigate the influence law of melt treatment time on the microstructure and mechanical properties of K488 alloy,the present work carried out 900℃/270 MPa high-temperature persistence tests on K488 alloy with different time of melt treatment[1625℃×(7–17 min)],respectively.In addition,in order to be informed of the microscopic mechanism by which the solid solution treatment temperature affects the mechanical properties of the alloy,this work also systematically characterized the microstructure of the K488 alloy before and after the mechanical property tests using scanning electron microscopy(SEM)and transmission electron microscopy(TEM).The results showed that the K488 alloy precipitated a uniform,larger-sized and more cubicγ′phase under the melt treatment condition of 12 min×1625°C.Compared with the endurance life under 7 min and 17 min melt treatment conditions,the endurance life of the alloy after 12 min×1625℃melt treatment reaches 204.9 h,indicating that 12 min is the optimal melt treatment time for K488 alloy.SEM and TEM suggest that the grain refinement under 12 min improves the strength of grain boundaries,and the higherγ′phase precipitates uniformly under 12 min×1625℃melt treatment.The higherγ′phase size and volume fraction effectively resisted the dislocation cutting,which improved the endurance life of K488 alloy.
作者
曲天壬
肖旋
李志涛
QU Tianren;XIAO Xuan;LI Zhitao(School of Materials Science and Engineering,Shenyang Ligong University,Shenyang Liaoning 110159,China)
出处
《辽宁化工》
2025年第9期1504-1508,共5页
Liaoning Chemical Industry
基金
国家自然科学基金(项目编号:51571191)。
