Experimental and numerical investigation of interface and mechanical properties of Al0.3CoCrFeNi/304L explosively weld composite plate

High entropy alloys (HEAs) have gained attention for their excellent properties, but research on combining them with conventional metals is limited. This study manufactured Al0.3CoCrFeNi/304L composite plates using explosive welding. Welding parameters were determined based on the theoretical weldability window. The detonation process and interface were analyzed using an advanced SPH-FEM algorithm. Interface morphology was characterized using OM, EDS, and EBSD, and mechanical properties were tested. Materials near the interface experienced extreme conditions, resulting in severe plastic deformation and wave interface generation. Interface inhomogeneity was caused by unsteady detonation and inclined collision. Collision velocity predicted by the SPH-FEM model matched theoretical calculations, and the predicted interface agreed with experimental results. Increased explosive charge led to more intense interface undulation and a thicker diffusion layer. EBSD showed a single-phase structure with non-uniform elements at the nanometer scale. The interface exhibited the highest deformation and grain recrystallization, along with plastic deformation and texture. Mechanical tests revealed that larger wave interfaces had higher hardness, improved tension, bending, and impact toughness, but worse shear performance. Explosive welding proved effective for achieving high-quality bonding between HEAs and conventional metals, offering promising possibilities for HEA and traditional metal composites.