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The present study deals with the effects of laser surface treatment on microstructure evolution and wear resistance of AISI H11 hot work tool steel in quenched and tempered condition. The most upper laser-affected zone is characterized by re-melted microstructure consisting of dendrite cells with fresh non-tempered martensite, retained austenite and inter-dendritic carbidic network. The subsolidus microstructure just beneath the re-melted zone represents the most laser surface hardened zone consisting of fresh non-tempered martensite with fine and coarse carbides as a result of overheating the original QT substrate microstructure. The highest microhardness values in the range from 775 to 857 HV were measured for the LSH microstructure and the most softened microstructure exhibited the minimum hardness of 530 HV. The laser treated samples showed the improvement of their surface wear resistance by 35%.

The use of laser ablation phenomenon with the “thermal effect” to produce surface textures, mainly lubricant micro-containers in the form of spherical micro-bowls in the surface layer of 100CrMnSi6-4 alloy of bearing steel. This is interesting research topic. The application the local (zonal) laser hardening of the steel surface layer on the surface of the bearing raceway or casts gives technological opportunities to deploy those technologies in the production process. The article presents the selected results of the own laboratory studies of hardness, microstructure and surface stereometry bearing steel 100CrMnSi6-4 in different states after volume hardening and low tempering, as well as those obtained as a result of laser surface texturing and laser pulsed hardening. The study results can be used to modify the surface layer of 100CrMnSi6-4 bearing steel and in the nearest future use ablative laser texturing of the rolling bearings treadmill surface in the production of lubricanting micro-containers, for improving the wear resistance tribological pair of roller – raceway in the friction conditions.

The present study deals with the effects of laser surface treatment on microstructure evolution and wear resistance of AISI H11 hot work tool steel in quenched and tempered condition. The most upper laser-affected zone is characterized by re-melted microstructure consisting of dendrite cells with fresh non-tempered martensite, retained austenite and inter-dendritic carbidic network. The subsolidus microstructure just beneath the re-melted zone represents the most laser surface hardened zone consisting of fresh non-tempered martensite with fine and coarse carbides as a result of overheating the original QT substrate microstructure. The highest microhardness values in the range from 775 to 857 HV were measured for the LSH microstructure and the most softened microstructure exhibited the minimum hardness of 530 HV. The laser treated samples showed the improvement of their surface wear resistance by 35%. [ABSTRACT FROM AUTHOR]

The paper presents results of research tribological properties laser hardened steel 42CrMo4. Parameter influencing on the quality of the hardened surface was laser head speed. The study was conducted on friction tester pin-on-disc type T-11, and a counter sample disc was silicate. Parameter determining the quality of the surface layer is the intensity of wear. Based on the results we obtain information about the laser head speed to temper steel 42CrMo4 so as to maintain a high resistance to wear. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to show results of laser treatment at cryogenic conditions of the Ti6Al4V alloy used for orthopedic applications. That modification process ought to bring beneficial changes of microstructure and residual stresses in the surface layer. The paper presents the abrasive wear of the base and laser remelted material in association with ceramics Al2O3. Despite the surface cracking after laser treatment the tribological properties in simulated body fluid have been substantially improved. [ABSTRACT FROM AUTHOR]