在真空条件下,将Ni和Al范加热到620℃，在1MPa压力下原位反应1h，然后再分别加热到750℃、950℃和1150℃、在5MPa的压力进行4h的扩散退火，制造出完全致密的Ni/Ni-Al金属间化合物微层板复合材料.复合材料中塑性的Ni层主要以微裂纹的桥联方式提高室温韧性.经1150℃退火生成的Ni3Al层同NiAl和Ni层界面结合非常牢固，可以有效地阻碍微裂纹的扩展，Ni3Al层可通过滑移与Ni层协调变形，使得复合材料在拉伸时显示出明显的应变强化和塑性流变，其平均的断裂强度和应变分别达到786MPa和12．8％．
Full-dellsity Ni/Ni-Al multilayer composites were successfully fabricated by in-situ reaction of Ni and Al foils at 620℃ for 1 hour under 1 MPa pressure, and then diffusion annealing for 4 hours at 750℃, 950℃ and 1150℃ respectively under 5 MPa pressure in vacuum.Ductile Ni layer in composites can greatly improve room-temperature fracture toughness bymicrocracks bridging and blunting. After annealing at 750℃ and 950℃, Al2O3 at the surface of Al foils before reaction remains at the interface of bilayer Ni2Al3 as inclusions, which makesinterface poorly bonded. But after annealing at 1150℃, Ni3Al layer is well-bonded with Ni and NiAl layer. So, the composites show significantly strain-hardening and plastic flow, its mean fracture strength and strain are 786 MPa and 12.8% respectively.
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