The superplastic forming/diffusion bonding (SPF/DB) process has been widely applied to manufacture the multi-layer components. In this paper, a four-layer hollow structure with squad grid was fabricated by SPF/DB process. The superplastic behavior of TA15 alloy was investigated by the uni-axial tensile tests at high temperature, and the maximum elongation of 911 % was obtained at 920 °C/0.001 s^− 1. The finite element method (FEM) of the four-layer structure was conducted, and the results showed that TA15 alloy was appropriate for fabricating this complex-shaped structure. Then the four-layer hollow structure was successfully fabricated by SPF/DB process at 920 °C with the target strain rate of 0.001 s^− 1. Finally, the microstructure, thickness distribution and mechanical property of the four-layer hollow structure were investigated. The grain size increased from 5 μm to 10 μm and the sound bonding interface was achieved. The thickness distribution was symmetrical in height direction. The compressive strength and the maximum bending load of the four-layer hollow structure was 50 MPa and 64.4 kN, respectively.

超塑性成形/扩散结合（SPF / DB）工艺已广泛应用于制造多层组件。本文采用SPF / DB工艺制造了具有方格结构的四层空心结构。通过高温下的单轴拉伸试验研究了TA15合金的超塑性行为，并在920°C / 0.001 s ^-1下获得了911％的最大伸长率。进行了四层结构的有限元方法（FEM），结果表明TA15合金适合于制造这种复杂形状的结构。然后通过SPF / DB工艺在920°C下成功制备了四层空心结构，目标应变率为0.001 s ^-1。最后，研究了四层空心结构的组织，厚度分布和力学性能。晶粒尺寸从5μm增加到10μm，并实现了声音键合界面。厚度分布在高度方向上对称。四层空心结构的抗压强度和最大弯曲载荷分别为50 MPa和64.4 kN。