1：Experimental Design and Method Selection:

The study employed selective laser melting (SLM) to fabricate Al2O3/P20 composites from powder mixtures with different Al2O3 contents. The methodology included analyzing surface morphology, densification behavior, microstructure evolution, and mechanical properties.

2：Sample Selection and Data Sources:

P20 mold steel powder and Al2O3 powder were used as feedstock. Three different systems of powder mixture were prepared with 0.5 wt%, 1 wt%, and 2 wt% of Al2O3 reinforcement.

3：5 wt%, 1 wt%, and 2 wt% of Al2O3 reinforcement. List of Experimental Equipment and Materials:

3. List of Experimental Equipment and Materials: Equipment included a vertical planetary ball mill (XQM-0.4, Changsha Tianchuang Powder Technology, China) for powder mixing, a commercially available SLM machine (HBD-100D, Shanghai Hanbang Lianhang Laser Technology, China) for sample fabrication, and various characterization tools like SEM, OM, XRD, and Rockwell hardness tester.

4：4, Changsha Tianchuang Powder Technology, China) for powder mixing, a commercially available SLM machine (HBD-100D, Shanghai Hanbang Lianhang Laser Technology, China) for sample fabrication, and various characterization tools like SEM, OM, XRD, and Rockwell hardness tester. Experimental Procedures and Operational Workflow:

4. Experimental Procedures and Operational Workflow: The powder mixtures were prepared by high-energy ball milling. SLM process parameters were optimized for sample fabrication. Microstructure characterization, phase analysis, hardness, and wear resistance tests were conducted.

5：Data Analysis Methods:

Data from SEM, OM, XRD, hardness tests, and tribological tests were analyzed to understand the effects of Al2O3 content on the composites' properties.