Geometrical dimensions could play a potential role in the function of laser cladding of nickel-base powder on the cold-rolled carbon steel substrate. The geometrical dimensions and their impact on the efficiency of the process of laser cladding of nickel-base powder (Ni -10wt% Al) on cold rolled 0.2% carbon steel substrate was investigated. This work focused on the effect of laser-specific energy input of CO2laser. The geometrical dimensions of cladding regions are including cladding width, cladding height, depth of dilution, contact angle, dilution area, cladding area, and heat-affected zone dimensions determinations. The laser power (1.8 kW) was used at different traverse speeds (1.5, 3.6, 5, 7.1, 8.6, 12.5 mm/s) with (3mm) laser beam diameter. The feed rate was kept constant after many preliminary claddings at approximately 11 g/min. Fluence values ranged from (48-400J/mm2), and the power density value was (255W/mm2). A minimum dilution percentage (25%) was obtained at the highest fluence value (400 J/mm2). Observations were measured using an optical microscope, scanning electron microscopy, and Image software. Obtained results indicated that the increase in the fluence leads to an increase in height of cladding, HAZ region but lower depth of dilution

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In this article a 1.8kW continuous wave of high power CO2 laser was used to clad of a titular composition of Ni – 10 wt% Al powder on cold rolled 0.2% carbon steel substrate. The feed rate was kept constant after many preliminary claddings at approximately 11 g/min.  In order to produce clads with different specific energies and interaction times, different traverse speeds were used in the range of 1.5 to 12.5 mm/s. The microstructure of substrate was changed at the heat affected zones under the variety of specific energies. The cladded coatings showed the presence of ɣ solid solution and β (NiAlFe) phases. A strong metallurgical bonding produced between the substrate and the clad coat at fluence higher than 48 J/mm2. The changing in microstructure were observed using both microscope and SEM. The microhardness was evaluated using Vickerʼs microhardness test. The microstructure of the substrate was ferrite and pearlite transformed to martensite at the region adjacent to the clad interface. It followed by a three regions can be classified, a grain growth zone (large grains of austenite/ferrite and pearlite), recrystallization zone (fine grains of austenite/ferrite and pearlite) and recovery zone (the structure has a little changes from the structure of low carbon steel). The microhardness testing result showed higher values for the clad regions compared with substrate. This study emphasize the possibility to develop a temporary new graded material.