由于Ni3Al基高温合金具有抗蠕变强度大、耐腐蚀、抗氧化等优异的高温性能.作为多组元的金属间化合物,合金组分的变化会直接影响到Ni3Al基高温合金的性能表现.为优化合金成分,获得最佳的合金性能,研究了晶界强化元素B含量变化对Ni3Al基高温合金组织和性能的影响.结果表明,合理控制B元素含量,能够增加合金的持久时间和塑性.当B元素含量在0.012％～0.021％时,合金在1100℃的拉伸性能和1050℃/100 MPa及1100℃/60 MPa的持久性能达到最佳.

By designing thin plate castings with different wall thicknesses, the influence of different wall thicknesses on the microstructure and properties of the Ni 3 Al superalloy was studied. As the wall thickness increased,the secondary dendrite wall of the alloy increased, and the segregation of Al, Ti, Hf, Mo, Cr, W and other elements in the structure changed. The tensile strength and tensile ductility of the alloy significantly increased.

Effect of solution and aging heat treatment on microstructures and stress rupture properties of a fourth generation Ni-based single crystal superalloy with content of 4.0wt% Re and Ru was investigated. The results show that the as-cast alloy exists significant composition segregation. Due to less Al and Ti elements, interdendritic gamma/gamma' eutectic content is low. During the solution heat treatment, the eutectic is almost dissolution after 1310 degrees C. However, the differences between dendrite core and interdendritic is completely eliminated until 1340 degrees C and the segregation of other elements except Re is significantly improved. The advantage of the fourth generation Ni-based single crystal is to improve the mechanical properties at high temperature, especially stress rupture properties. After solution and aging heat treatment, the stress rupture life of DD476 is about twice than that of the second generation single crystal superalloy at 950 degrees C / 300 MPa and is more than 10 times compared with the second generation single crystal superalloy MC2 at 1150 degrees C/100 MPa. There is no TCP (topologically close-packed) precipitation during the whole heat treatment because of the addition of Ru element in DD476.