Metal matrix composites (MMCs) have many industrial applications in different sectors, e.g.: automobile and aerospace. However, due to hard ceramic reinforcing components in MMCs, difficulties can arise when machining via conventional manufacturing processes. Excessive tool wear is especially problematic. Laser assisted machining (LAM) is one of the technologies that enable machining of hard-to-cut materials. In laser assisted cutting, the workpiece area is heated directly by a laser beam before the cutting edge. The work reported here concentrates on improving Al/SiC composite's machinability by laser assisted machining, when compared to conventional turning process. Influence of laser's beam during laser assisted turning on cutting force, tool wear and machined surfaces roughness was investigated. This research was carried out for cubic boron nitride (CBN) and sintered carbide inserts. The results obtained with the laser assisted machining were compared to those obtained in conventional turning

Laser cladding technology enables the regeneration or manufacturing of machine parts with the improved surface layer properties. The materials applied during the laser cladding processes very often contain hard and wear-resistant tungsten carbide (WC) particles. However, the parts obtained after the laser cladding have usually unsatisfactory surface quality and thus require post-process finishing. In addition, the content of WC particles causes that clad layers are difficult to cut. Therefore, in order to improve their machinability, the laser-assisted machining (LAM) technology can be applied. Nevertheless, the material removal mechanisms during LAM of WC/NiCr clad layers are not recognized. Thus, this study is focused on the estimation of minimum uncut chip thickness and analysis of cutting forces which are important factors describing the chip decohesion process. The proposed method is based on the novel approach dedicated directly to the oblique cutting, considering the zeroth tangential force increment located onto rounded cutting edge. The experimental procedure involves cutting force component (F _c , F _f , F _p ) measurements in the range of variable cutting conditions, as well as the cutting tool’s micro-geometry inspection. On the basis of the measurements carried out, the force regression equations are formulated and subsequently applied to the determination of tangential force expression. Subsequently, the minimum uncut chip thickness is calculated on the basis of the equation derived from the zero tangential force increment condition and presented in function of cutting speed. The obtained results enable the effective selection of the cutting parameters during LAM of WC/NiCr clad layers.

This study concentrates on describing effects of laser heat treatment of Monel 400 and laser alloying its surface with boron. Surfaces without and with initial boron layers of two different thicknesses (100 and 200 μm) were processed using diode laser. Laser beam power density was constant and equal to 178.3 kW/cm². To determine the influence of laser beam scanning velocity on final properties of treated surfaces, laser beam scanning velocity was set on four different values: 5, 25, 50, and 75 m/min. Microstructures of pure Monel 400 and Monel 400 alloyed with 100 μm boron content are composed of dendrites. Areas laser alloyed with 200 μm boron layer contain mainly nickel borides. Boron addition in Monel 400 surface results in microhardness increase in which the level depends on boron content and the laser beam scanning velocity. Increasing the thickness of initial boron layer and speeding up the laser beam lead to obtain higher microhardness. On the other hand, areas laser alloyed with 200 μm boron layer using laser beam scanning velocity equal to 75 m/min contain deep cracks which propagate from the surface through the produced layer. Furthermore, it was found that the depths of laser heat-treated areas depend significantly on the boron content. As the result of differences in thermal properties between Monel 400 and boron, depth of re-melted zones in some conditions does not lower with increasing laser beam scanning velocity.