Page 13 - НАЦІОНАЛЬНА АКАДЕМІЯ НАУК УКРАЇНИ
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               fixed abrasive, the erasure of all phases of the modified layer occurs layer-by-layer

               almost  uniformly  over  the  entire  friction  surface.  In  this  case,  there  were  no  deep

               traces of abrasion and avulsion caused by the grasp of the abrasive wheel with the

               sample surface. This is due to the increased hardness of the matrix around the SiC

               grains,  which  is  micro-reinforced  with  dispersed  carbides  Al 4C 3,  Al 4SiC 4,  and

               therefore less prone to plastic flow as prerequisites for avulsion.

                      The  low  wear  resistance  of  the  alloy  laser-modified  by  SiC  particles  during

               friction with a non-fixed abrasive is since free abrasive falling into the gaps between

               solid  SiC  particles  easily  destroys  the  soft  matrix,  releasing  them.  After  this,  the

               particles are pulled out without a special effort by a rubber circle. The wear resistance

               under  friction  with  a  non-fixed  abrasive  depends  on  the  distance  between  the  SiC

               particles because the modified surface of the aluminum alloy is destroyed primarily

               around these particles.

                      Since the work purpose was to replace galvanic chrome plating, it was found

               that laser modification under friction with a rigidly fixed abrasive increases the wear

               resistance of the output alloy by 40-95 times, and galvanic chrome plating only by


               35 times, however, in case of friction with non-fixed abrasive, laser modification was
               not very effective. Therefore, was justified the choice of another method of surface


               hardening. This method turned out to be the method of thermal spraying, as one of
               the most productive and simple to implement.


                      Therefore,  the  structure  and  wear  resistance  of  the  thermal  coatings  of  the
               FeCr-VC  system  obtained  by  high-speed  flame  spraying  (HVOF)  and  plasma


               spraying in dynamic vacuum (PSCDV) were studied.

                      The structures of the VC-FeCr systems coatings, obtained by high-speed flame

               spraying (HVOF) on equipment in which propane oxygen (Diamond Jet Hybrid gun)

               and kerosene - oxygen (JP5000 gun) served as fuel, were almost identical. They are

               characterized by a typical lamellar structure, when slightly deformed drops of powder

               mixtures  used  to  obtain  coatings  are  crystallized,  lamellas  with  barely  noticeable

               oxide  layers  between  them  form.  Against  the  background  of  the  matrix  phase  of

               ferrochrome,  stochastically  dispersed  precipitates  of  VC  carbides  with  a  size  of
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