© Copyright by International OCSCO World Press. All rights reserved. 2009 VOLUME 32 ISSUE 1 January 2009 Research paper 53 of Achievements in Materials and Manufacturing Engineering of Achievements in Materials and Manufacturing Engineering Structure and properties of the laser alloyed 32CrMoV12-28 with ceramic powder L.A. Dobrzański a, *, K. Labisz a , A. Klimpel b a Division of Materials Processing Technology, Management and Computer Techniques in Materials Science, Institute of Engineering Materials and Biomaterials, Silesian University of Technology, ul. Konarskiego 18a, 44-100 Gliwice, Poland b Welding Department, Silesian University of Technology, ul. Konarskiego 18a, 44-100 Gliwice, Poland * Corresponding author: E-mail address: leszek.dobrzanski@posl.pl Received 15.10.2008; published in revised form 01.01.2009 Manufacturing and processing AbstrAct Purpose: The work was performed for the reason to determine the laser treatment parameters, particularly the laser power, to achieve a high value of layer hardness for protection of this hot work tool steel from losing their work stability and to make the tool surface more resistant for work. The purpose of this work was also to determine technological and technical conditions for remelting the surface layer with HPDL. Design/methodology/approach: The main methodology results of new laser treatment techniques applied in metal surface technology are presented and discussed. There is presented laser treatment with remelting of hot work tool steel 32CrMoV12-28 with ceramic powders especially carbide - TaC, as well as results of laser remelting influence on structure and properties of the surface of the hot work steel, carried out using the high power diode laser (HPDL). Special attention was devoted to monitoring of the layer morphology of the investigated material and on the particle occurred. Optical and scanning electron microscopy was used to characterize the microstructure and intermetallic phases occurred. Findings: There was achieved a layer without cracks and defects as well as has a considerably higher hardness value compared to the non remelted material. The hardness value increases according to the laser power used so that the highest power applied gives to highest hardness value in the remelted layer. Research limitations/implications: There were four choused laser powers used and implicated by one process speed rate. Also one powder in form of TaC was used for alloying with the particle size of 10 μm. Practical implications: This work helps to use the laser treatment technique for alloying and remelting of hot work tool steel. Originality/value: The originality of this work is based on applying of High Power Diode Laser for improvement of steel mechanical properties. Keywords: Surface treatment; Heat treatment; Hot work tool steel; Laser melting