# Evaluation of the Effectiveness of Surface Defect Removal by Slide Burnishing
## 1 Introduction  
Burnishing is one of the methods for shaping the surface texture and physical properties of the surface layer of manufactured objects. In the burnishing process, the tool is pressed against the workpiece with a specified force, and the tool component, in direct contact with the workpiece surface, the so-called burnishing component, moves along this surface in a rolling or sliding manner [1, 2]. Depending on the shape of the burnishing element rolled over the workpiece surface, a distinction is made between ball burnishing and rolling burnishing [3, 4]. In slide burnishing, the burnishing element usually has a spherical cup with a defined radius on its end [5]. Slide burnishing is used as a finishing operation for workpieces of various shapes. In work by [PERSON] et al. [6], it was shown that a reduction in the roughness of the machined surface could be achieved by sliding burnishing of the cylindrical surface of an EN AW-2011 aluminum alloy workpiece. A study by [PERSON] and [PERSON] showed that the combined ball-end milling and burnishing processing of additively manufactured prismatic objects made of AlSi10 Mg aluminum alloy, performed on a 5-axis CNC machine tool, made it possible to reduce surface roughness and shape compressive residual stresses [7]. A study by [PERSON] et al. demonstrated that slide burnishing of valve stems made of 317 Ti steel led to improved surface roughness, increased microhardness, and the generationof compressive residual stresses, which resulted in an approximately 4-fold increase in the failure-free operation time of the valves [8]. Research by [PERSON] et al. showed that slide burnishing of 42 CrMo4 steel discs with a hardness of 40 \(\pm\) 2 HRC improved the surface layer and tribological properties of the workpieces [9]. The effects of slide burnishing greatly depend on the technological conditions of this process, such as the shape, dimensions, and material of a burnishing element, burnishing parameters, and lubricating liquids. According to [PERSON] et al., diamond elements with a spherical cup are most often used for slide burnishing (84%), while hard alloy (11%) and hardened steel (4%) elements are used to a lesser extent [5]. [PERSON] et al. used burnishing elements with the radius R = 1 \(\div\) 2.5 mm and made of synthetic diamond composite for slide burnishing of X19 NiCrMo4 steel samples, which resulted in a 23.8% increase in their fatigue strength compared to turned samples [10]. A special tool with a spherical diamond tip for damping vibrations generated by the technological machine bed was used in the cryogenic diamond burnishing process of 17-4 PH steel [11]. [PERSON] et al. obtained a significant reduction in surface roughness and increased microhardness of the surface layer of HV250 normalized carbon steel samples by subjecting them to slide burnishing using non-rotating silicon nitride ceramic balls with the diameters of 6.35 mm and 12.7 mm [12]. [PERSON] et al. investigated the surface texture of 3.1645 aluminum alloy samples after slide burnishing using a burnishing element in the form of a sliding pin made of DLC-coated cemented carbide ended with a 10 mm diameter spherical surface [13]. The results of a study investigating the effects of selective laser melting parameters of Ti6 Al4V titanium alloy samples and slide burnishing parameters of these samples on the hardness of their surfaces were reported in [14]. A study by [PERSON] et al. showed that slide burnishing performed using a 2.5 mm radius diamond tool on X2 CrNiMo17-12-2 corrosion-resistant steel specimens resulted in reduced roughness and increased surface hardness of these specimens, with the burnishing effects depending on the feed rate and burnishing force [15]. The beneficial effect of diamond slide burnishing on the surface roughness of aluminum matrix composites samples was also found in [16]. [PERSON] et al.