【摘要】 采用力学压缩试验、扫描电镜和X射线衍射方法研究了Nb元素对于Ti50Ni42Al8合金的力学性能和微观组织结构的影响。结果表明,Nb能够显著提高合金从室温到700℃之间的强度。在600℃时,Ti50Ni40Al8Nb2合金的压缩屈服强度和比强度分别为1237MPa和216MPa/(g.cm-3),超过Rene95高温合金。微观组织观察及成分分析表明,Nb元素在基体和强化相Ti2Ni(Al)中固溶,促进强化相的弥散析出和细化,并导致高强富Nb相的析出,从而提高了合金的强度。更多还原

【Abstract】 The effects of Nb on the microstructure and properties of Ti50Ni42Al8 alloys are studied through compressive test,scanning electronic microscopy and X-ray diffraction measurements.The results indicate that the compressive strength of Ni42Ti50Al8Nb2 in the range from room temperature to 700 ℃ significantly increases with the Ni content.The compression strength and specific strength at 600 ℃ are 1 237 MPa and 216 MPa/(g·cm-3),respectively,exceeding those of superalloy Rene95.The results of microstructure observation and composition analysis show that the addition of Nb induces the solution strengthening,accelerates the precipitation and refinement of Ti2Ni(Al)phase,and forms Nb-rich phase with high strength,leading to the strengthening of the alloy.更多还原