<p>TA15/AlSi10Mg functionally graded material (FGM) was produced via laser deposition manufacturing (LDM). The microstructural characteristics were analyzed using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and microhardness testing. This study clarified the regularities of phase changes and the mechanisms of crack formation within the graded interface. The TA15/AlSi10Mg FGM designed volume fraction gradient was as follows: Layer I: 100% TA15; Layer II: 75% TA15 + 25% AlSi10Mg; Layer III: 50% TA15 + 50% AlSi10Mg; Layer IV: 25% TA15 + 75% AlSi10Mg; Layer V: 100% AlSi10Mg. It was found that the primary phases in the TA15/AlSi10Mg FGM evolve along the gradient direction as follows: Ti(I) → Ti₃Al(II) → TiAl + Ti₅Si₃(III) → TiAl₂ + TiAl + Ti₅Si₃(IV) → Al + Si(V). Cracks were observed in Layer IV. Macroscopic cracks initiated at the top surface of this layer and propagated downward, perpendicular to the deposition plane. Microcracks predominantly originated at the edges and tips of Ti₅Si₃ precipitates. The formation of macroscopic cracks was primarily driven by transverse tensile stresses induced by constrained solidification in Layer IV. The core mechanism of microcrack formation was stress concentration around Ti₅Si₃ precipitates, induced by accumulated residual tensile stress during cooling and subsequent thermal cycles after the deposition of Layer IV.</p>