An enhanced Ni50A composite coating was formed on the AISI 1045 steel surface using Ti, B4C, and Ni50A powders. The work meticulously examined the effects of various process parameters, including laser power (800, 1200, and 1600 W) and scanning speed (4, 6, and 8 mm/s), as well as different Ti/B4C powder ratios (2:1, 3:1, and 4:1, mol.%) on the defect, hardness, wear resistance, and corrosion resistance of the coating. The microstructure of the coating showed that TiB2 and TiC synthesized in situ were the key phases for coating enhancement, and there were a variety of solid solutions (FeNi3 and Cr2Ni3). TiB2 particles showed dark gray hexagons and long rectangular blocks. The TiC particles mainly appeared in light gray dendritic shapes, occasionally petal-shaped and equiaxial forms, and grew around TiB2. The research results showed that increased laser power and the Ti/B4C ratio decreased coating hardness and wear resistance. When the scanning speed increased, the hardness and wear resistance of the coating were significantly improved. The main wear mechanisms of the TiB2–TiC ceramic phase coating were oxidative wear and abrasive particle wear. Besides, the higher laser power and Ti/B4C ratio reduced the defect rate of the coating and enhanced the corrosion resistance. However, as the scanning speed increased, the defect rate increased, which decreased the corrosion resistance of the coating. The comprehensive performance evaluation showed that under the conditions of the laser power of 1200 W, a scanning speed of 8 mm/s, and a Ti/B4C ratio of 4:1, the coating exhibited optimal performance (dilution rate = 10.928±0.090%, defect rate = 8.657±0.128%, hardness = 63.300±1.159 HRC, wear volume = 0.0149±0.000100 mm3, Ecorr = −0.565±0.001 V, Icorr = 1.058E−06±1.528E−09A⋅cm2). The results provide an important basis for research on the high-quality and efficient strengthening technology and performance of refractory alloys.