The interface formation and its mechanism of ZG42CrMo/BTMCr26 bimetallic castings, including hammerheads and thin plates, are investigated in this work. By extending the pouring interval, the interface area characteristic changes from local mixing solidification to shrinkage-filling solidification. Both interfaces exhibit high binding and tensile strength, exceeding 500 MPa. The casting bimetallic plates display a straight sequentially solidified interface with a carbide-free zone of approximately 16.5 μm. The interfacial adhesion and tensile strength of the plates also exceed 500 MPa. Based on the obtained results and theoretical basis, over 20 types of crusher hammers weighing between 7 and 250 kg, as well as various wear plates have been produced. Both castings exhibit high pass rate a long lifespan.