Effect of Ti addition on the Microstructure and Wear Resistance of an arc-melt and surface-laser-remelt AISI H13 Steel

H13 tool steel is used in high-performance applications due to its favorable strength, hardness, and wear resistance. Nevertheless, conventional processing often leads to coarse microstructures and carbide precipitation, which may impair tribological performance. This study investigates the titanium influence additions (0.4 and 0.8 wt.%) on H13 steel produced by arc-melting and subsequently surface-remelted via laser surface modification. Titanium promotes stable carbide formation by binding carbon, potentially reducing retained austenite and tempering the brittleness associated with high carbon content. Microstructure was characterized using optical microscopy, SEM-EDS, and EBSD. Hardness was measured, and wear behavior was assessed through fixed-ball cratering tests (2.825 N load, 300 rpm, up to 120 min) and reciprocating ball-on-flat sliding tests (3–10 N load, 10 mm/s at 1 Hz, up to 60 min). Results show that Ti addition favors TiC formation while suppressing other carbides. Prior-austenite grains decreased with Ti addition, while final martensitic/ferritic increased grain size, from 1.27 ± 0.03 μm in unmodified H13 to 1.37 ± 0.03 μm in H13 + 0.8Ti. Hardness decreased from 767 ± 4 HV to 581 ± 4 HV. Despite lower hardness, Ti-modified alloys displayed reduced friction coefficients and comparable or enhanced wear resistance, especially after laser remelting. This improvement is attributed to a lubricious tribo-oxide layer and TiC particles acting as a third-body, reducing adhesive contact and promoting rolling friction. Laser remelting further refined TiC and stabilized the tribological system. These findings indicate that Ti alloying combined with rapid solidification is a possible strategy to tailor the wear performance of H13 steel.