A higher yield strength of parent phase in shape memory alloys is necessary for achieving a higher recovery stress. Fe alloying combined with grain boundary engineering (GBE) were investigated to improve the yield strength of ductile Cu17Al11Mn alloy. Results showed that the precipitation of low strength ductile α phase through the GBE remarkably enhanced the ductility while not obviously reducing the yield strength in the step-quenched Cu17Al11Mn4.5Fe alloy due to the precipitation of nanoscale κ phase inside them. Compared to the Cu17Al11Mn alloy, a 200 MPa higher yield strength and better ductility could be realized in the Cu17Al11Mn4.5Fe alloy step-quenched into two-phase region between 993 K and 1003 K. The recovery strains of ∼6.5% could be guaranteed in the step-quenched Cu17Al11Mn4.5Fe alloy. The Fe alloying combined with the GBE through the step-quenching will be a direction for developing ductile CuAlMn based alloys with both high strength and recovery strain.

形状记忆合金中母相较高的屈服强度是实现较高恢复应力的必要条件。研究了Fe合金化结合晶界工程（GBE）以提高韧性Cu17Al11Mn合金的屈服强度。结果表明，通过GBE析出的低强度韧性α相显着提高了阶梯淬火Cu17Al11Mn4.5Fe合金的延展性，但由于内部析出纳米级κ相，其屈服强度没有明显降低。与 Cu17Al11Mn 合金相比，Cu17Al11Mn4.5Fe 合金在 993 K 和 1003 K 之间逐步淬火成两相区，可以实现 200 MPa 更高的屈服强度和更好的延展性。在 6.5% 的恢复应变可以保证阶梯淬火的Cu17Al11Mn4.5Fe合金。