To further reduce the charge amount and improve the bonding quality of titanium/steel composite plates, explosive welding experiments of TA1/Q235 were conducted using a low detonation velocity explosive (53#) under the guidance of the explosive welding lower limit principle, with flyer plate thicknesses of 1, 2, and 4 mm and gaps of 3, 6, and 8 mm, respectively. The weldability window for titanium/steel explosive welding was calculated, and a quantitative relationship between dynamic and static process parameters was developed. A β-Vp high-speed inclined collision model was proposed, and two-dimensional numerical simulations for the explosive welding tests were performed using the SPH algorithm, revealing the growth evolution mechanisms of the typical waveform morphology characteristics. Through microstructural characterization methods such as OM, SEM, EDS, and EBSD, in conjunction with mechanical property tests including shear strength, bending performance, and impact toughness, the microstructural morphology and mechanical properties of the interfaces in TA1/Q235 explosive-welded composite plates were investigated. The results show that the quality of interface bonding is excellent, presenting typical waveform morphology, with an average interface shear strength above 330 MPa and an average impact toughness exceeding 81 J. All samples can be bent to 180° without significant delamination or cracking defects.