# Evaluation of the Effectiveness of Surface Defect Removal by Slide Burnishing
## 3 Results and Discussion
### Surface Roughness  
Figures 8-10 show the influence of the technological parameters of slide burnishing on the 2D surface roughness parameters. All analyzed 2D surface roughness parameters after slide burnishing are lower than those after grinding. The application of a higher burnishing force (F = 150 N) results in more intensive plastic deformation of the material. The plasticized material fills the depression created by grinding. This causes a reduction in the amplitude parameter Ra (Figure 8) and the height parameter Rt (Figure 9). The Ra and Rt parameters are 70% to 87% lower compared to the values after grinding, which may have a positive effect on tribological and fatigue life. An increase in fatigue life, associated with a decrease in surface roughness parameters, was obtained after slide burnishing of C45 steel workpieces in our previous study [31]. Regardless of the applied force F, an increase in burnishing feed causes the parameters Ra, Rt, Rpk, Rk, and Rvk to increase. This can be explained by an increase in the distance between successive passes of the burnishing tool. A larger distance between the tool paths results in incomplete deformation of micro-irregularities after grinding.  
Whatever the technological parameters of slide burnishing, the parameters of the Abbott-Firestone curve change (Figure 10). After slide burnishing, the Rpk parameter is lower from 42% to 70%, Rk from 74% to 85%, and Rvk is lower from 80% to 91% with respect to its value after grinding. This means that the performance properties of the workpieces have improved. The reduced Rpk parameter value means an increase in the service life of mating components after the lapping time. The low Rk value allows us to assume an increase in the load capacity of the surface after slide burnishing.  
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\end{table}
Table 4: Surface topography and 3D parameters after slide burnishing conducted with variable technological parameters.  
Figure 8: Influence of the technological parameters of slide burnishing on the surface roughness parameter Ra of a thin-walled C45 steel element. The white bar indicates the surface roughness (parameter Ra) before slide burnishing.  
Figure 9: Influence of the technological parameters of slide burnishing on the surface roughness parameter Rt of a thin-walled C45 steel element. The white bar indicates the surface roughness (parameter Rt) before slide burnishing.  
Compared to the results of previous studies, an analysis of the 2D surface roughness parameters obtained in this work demonstrates that the values of the Ra and Rt parameters are similar to those obtained in [15], but lower than those reported in [12]. All analyzed surface roughness parameters are from 42% to 91% lower than before slide burnishing, which is a better result than in [10]. The minimum value of the Ra parameter was obtained for F = 150 N and f = 0.03 mm/rev (Ra = 0.17 \(\upmu\)m), which is more than 3 times higher than the value obtained after burnishing of D16T aircraft aluminum alloy [32]. As for the Abbott-Firestone curve parameters, the reduction in these parameters is similar to that observed in our previous work [23], despite the lower burnishing force, yet greater than in [24].