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               particle size of SiC, the temperature of heating of the samples immediately before

               surface modification by laser. It was revealed that with increasing linear energy of the

               laser beam, the thickness of the modified layer increases and the volume content of

               SiC  particles  in  it  increases.  With  an  increase  in  linear  energy  of  more  than

               1100 J/cm, SiC particles intensively dissolve in the aluminum melt, which affects the

               characteristics of the layer. Therefore, it was accepted that the linear heat is optimal

               in  the  range  of  740  ...  1100  J/cm.  At  a  linear  energy  of  740  J/cm,  the  uniform

               distribution of SiC particles over the thickness of the modified layer is retained only

               to a depth of less than 0.9 mm, while at 1100 J/cm - up to 1.1 mm.

                      At a linear energy of 1100 J / cm, with an increase in the particle size of SiC

               from  50  to  150  μm,  the  thickness  of  the  modified  layer  increases  from  0.75  to

               1.5 mm, and their volumetric content in it increases from 16 to 20.5%.

                      X-ray  spectral  and  X-ray  phase  analysis  of  the  layers  modified  with  SiC

               particles confirmed the presence of silicon carbide particles and aluminum carbides in

               them. The mechanism of the formation of laser-modified (by SiC particles) surface

               layers on aluminum alloys is disclosed. It has been established that in the upper zone


               of the modified layer, where the melt temperature is the highest, globular Al4SiC4
               particles  and  needle-shaped  Al 4C 3  particles  in  the  lower  zone  are  formed  due  to


               aluminum diffusion into the  SiC surface layer. When the aluminum content in the
               surface  layer  of  SiC  particles  reaches  8  ...  10  wt.%,  due  to  stress,  the  resulting


               particles of aluminum carbides are separated from the surface of SiC particles and
               distributed by the convective flows throughout the volume of the modified layer.


                      It  was  established  that  during  friction,  the  wear  resistance  of  laser-modified

               layers depends on the following factors: the chemical composition of the aluminum

               alloy, the volume content of SiC particles in the modified layer, the linear energy of

               the laser beam, the overlap width of the laser tracks, and the direction of abrasive

               wear.

                      Assessing the effect of the chemical composition of aluminum alloys (АМг1,

               АD35, В95) on the wear resistance of laser-modified (by SiC particles) layers, it was

               found that with an increase the zinc content in the alloy, the wear resistance of these
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