Fig. 1. Morphologies of mixed powder and schematic of laser alloying process. (a) Schematic of laser alloying process; (b) pre-placed powder morphology of LA1 sample ; (c) pre-placed powder morphology of LA2 sample ; (d) pre-placed powder morphology of LA3 sample

Fig. 2. XRD patterns of LA1, LA2, and LA3 samples

Fig. 3. Thermodynamic calculation results of in‑situ reactions in melt pool. (a) ΔG_T in chemical reactions (1) and (2); (b) ΔG_T before and after formation of 1 mol reactants

Fig. 4. Cross-sectional morphologies of alloyed layers. (a) Cross-sectional morphology of alloyed layer of LA1 sample; (b) element distributions; (c) cross-sectional morphology of multi-lap alloyed layer

Fig. 5. SEM morphologies of microstructures in alloyed layers of samples. (a)‒(c) Top; (d)‒(f)middle part; (g)‒(i) bottom

Fig. 6. Typical microstructures and compositional analysis of alloyed layer of LA1 sample. (a)(b) Typical microstructures; (c)‒(f) EDS analysis results

Fig. 7. Composite structure in alloyed layer. (a) SEM morphology; (b) EDS line scanning area; (c) EDS line scanning result

Fig. 8. Calculation process and statistical results of orientation relationship for α-Al, TiC, and TiB₂. (a) Schematics of crystal plane and crystal orientation and calculation data; (b) statistical graph of f_r and f_d calculation results

Fig. 9. Hardness and friction wear test of alloyed layers and substrate. (a) Microhardness distribution; (b) friction coefficient curve

Fig. 10. Wear abrasion profiles and morphologies of substrate and specimen. (a)(e)(i) Substrate; (b)(f)(j) LA1; (c)(g)(k) LA2; (d)(h)(l) LA3