摘要
采用双籽晶制备第二代镍基单晶高温合金DD5合金双晶试板并加工成力学试样,研究小角度晶界对DD5合金中、高温条件下拉伸、持久性能的影响。结果表明:在760℃拉伸条件下,晶界角度小于14.8°时,试样抗拉强度大于1100 MPa,伸长率大于8%,断面收缩率大于14%,晶界角度大于14.8°后,抗拉强度、伸长率以及断面收缩率随着晶界角度的增大而下降,屈服强度则没有显著变化;在980℃拉伸中,晶界角度小于19.4°时,试样抗拉强度大于760 MPa,屈服强度大于630 MPa,伸长率以及断面收缩率则随晶界角度的增大而快速下降,至19.4°时,伸长率下降至1.4%,断面收缩率下降至2.8%;在870℃/551 MPa持久条件下,当晶界角度小于7.8°时,试样持久寿命大于110 h,伸长率大于19.8%,断面收缩率大于23.1%,当晶界角度大于7.8°后,试样持久寿命、伸长率以及断面收缩率随晶界角度的增大而快速下降。
The effects of low angle grain boundaries on the tensile properties and stress rupture properties of second generation single crystal superalloy DD5 at medium temperature and high temperature were investigated.The test plates were prepared by using seeds and processed into mechanical samples.The results show that the tensile strength at 760℃ is higher than 1100 MPa,the elongation is higher than 8% and the percentage reduction of area is higher than 14% when the angle is below 14.8°.The tensile strength,elongation and percentage reduction of area are decreased when the angle is above 14.8°.But the yield strength shows no difference.The tensile strength at 980℃ is higher than 760 MPa,the yield strength is higher than 630 MPa,the elongation and percentage reduction of area are decreased quickly when the angle is below 19.4°.The elongation is 1.4%,the percentage reduction of area is 2.8% when the angle is 19.4°.The rupture life at 870℃/551 MPa is higher than 110 h,the elongation is higher than 19.8%and the percentage reduction of area is higher than 23.1%when the angle is below 7.8°.But they are decreased quickly when the angle is above 7.8°.
作者
秦健朝
崔仁杰
黄朝晖
QIN Jian-chao;CUI Ren-jie;HUANG Zhao-hui(Key Laboratory of Advanced High Temperature Structural Materials,AECC Beijing Institute of Aeronautical Materials,Beijing 100095,China)
出处
《材料工程》
EI
CAS
CSCD
北大核心
2020年第10期114-122,共9页
Journal of Materials Engineering
关键词
高温合金
小角度晶界
持久寿命
拉伸性能
superalloy
low angle grain boundary
rupture life
tensile property
