A four-fold-degenerate three-dimensional (3D) Dirac point, represents a degenerate pair of Weyl points carrying opposite chiralities. Moreover, 3D Dirac crystals have shown many exotic features different from those of Weyl crystals. How these features evolve from 3D Dirac to Weyl crystals is important in research on 3D topological matter. Here, we realized a pair of 3D acoustic Dirac points from band inversion in a hexagonal sonic crystal and observed the surface states and helical interface states connecting the Dirac points. Furthermore, each Dirac point can transition into a pair of Weyl points with the introduction of chiral hopping. The exotic features of the surface states and interface states are inherited by the resulting Weyl crystal. Our work may serve as an ideal platform for exploring exotic physical phenomena in 3D topological semimetals.

四倍简并的三维（3D）Dirac点代表带有相反手性的简并的Weyl点对。此外，3D Dirac晶体显示出许多与Weyl晶体不同的奇异特征。这些特征如何从3D狄拉克晶体演变为Weyl晶体对于3D拓扑物质的研究非常重要。在这里，我们通过六角形声晶体中的带反转实现了一对3D声学狄拉克点，并观察了连接狄拉克点的表面状态和螺旋界面状态。此外，随着手性跳跃的引入，每个狄拉克点都可以转变为一对Weyl点。表面态和界面态的奇异特征被生成的Weyl晶体继承。