Multi-metal additive manufacturing enables the creation of multi-metal architectures that exceed the intrinsic property limits of single alloys by spatially combining complementary materials within a single component. Such capability is critical for next-generation aerospace systems, energy technologies, biomedical devices, and national defense applications. Despite its promise, the widespread use of multi-metal additive manufacturing is limited by cracking at dissimilar-metal interfaces, which undermines reliability and discourages industrial adoption. This Faculty Early Career Development Program (CAREER) project addresses this fundamental challenge by developing a science-based understanding of how and why interfacial cracks form during processing and how they can be avoided. By enabling defect-free multi-metal components, the project supports U.S. competitiveness in advanced manufacturing while contributing to workforce development. Integrated research, education, and outreach activities engage K–12 students, undergraduates, and graduate researchers through hands-on design-to-manufacture challenges and a new forensic learning framework that emphasizes evidence-based reasoning, creativity, and critical thinking. The research objective is to develop a rigorously validated multi-physics framework that predicts process-induced interfacial cracking in multi-metal additive manufacturing. The project integrates multicomponent heat and mass transport, grain-scale crystal plasticity, and coupled fracture mechanics to capture the interactions among residual stress evolution, liquid-metal embrittlement with Kirkendall porosity, and brittle intermetallic layer formation. Two representative alloy systems, Cu-10Sn/904L stainless steel and Ti-6Al-4V/AlSi10Mg, are studied to isolate distinct cracking mechanisms and validate the framework across different metallurgical regimes. Model predictions are validated using in-operando synchrotron X-ray imaging and diffraction and hig