This paper presents the effects of modeling the stress in the burnished layer of a complex spatial surface that was previously milled. A spatial kinematic-geometric model of the surface structure after milling is used. This paper presents the results of a numerical experiment on the synergic influence of the technological milling and burnishing parameters responsible for the final state of the geometric structure of a surface on the post-machining stress in the surface layer. The stress in the surface layer plays an important role because it is frequently responsible for the development of cracks, corrosion, and cavitation (in the surface area of injection aluminum molds, press tools, and core cutters). A proper understanding of the mechanisms responsible for the origin and development of residual stress will be conducive to the improvement of functional properties and longer tool life.

Miniaturization is a dominant trend in machine building which requires the use of advanced techniques of manufacturing and control. Apart from dimensional and shape precision of miniaturized components, surface geometry, particularly roughness and so-called microroughness that results from the use of advanced treatment techniques, plays an important role in correct assembly, reliable operation and durability of the whole machine. The selection of filtration method in surface geometry of micro-objects can be a substantial problem. The authors of the paper propose to use wavelet filtration in digital processing of a point cloud to remove measurement noise and not to change the surface character of the measured object. Also, the authors propose, in this paper, some criteria for selecting the number of wavelet filtration levels based on minimalization of the RMS value. It is supposed to improve the efficiency of low-pass filtration of small areas of the surface, particularly compared to traditional λs Gaussian filtration.

The paper extends the concept of cut edge quality and examines the fibre laser cutting process. A Prima Power Platino Fiber Evo device with a reference speed (RS) of 3500 mm/min was used for laser cutting. In order to analyse the influence of the laser cutting speed on the cut edge quality of X5CrNi18-10 stainless steel sheets, macroscopic studies were conducted on a stereoscopic microscope and surface stereometry on a confocal microscope. The obtained results were analysed to evaluate 2D and 3D parameters. These parameters make it possible to determine the cut edge quality and the susceptibility to the application of protective coatings. It was observed that the value of the Sa parameter is the highest for a cutting speed equal to 130% of RS. The Sz parameter is similar, while the Sk, Spk and Svk parameters rise as the speed increases, which is a negative phenomenon. Comparative tests were also conducted for four specimens made at cutting speeds of 70%, 85%, 100% and 115% of RS, respectively. It was found that the laser cutting speed has a significant impact on the cut edge quality and that stainless steel can be cut while maintaining the technological regime at 115% of RS.

Manufacturers of adhesives for industrial use determine the strength of adhesive joints during shear tests. Most often, components made of the same material are joined. In contrast, the roughness of the surfaces to be joined results from the use of a specific surface treatment technology. In adhesive manufacturers’ recommendations for metal-to-metal joints, surface technologies can be found without specifying numerical requirements for roughness. Modern techniques for shaping the geometric accuracy of components allow the formation of determined irregularities on the surface, which are characterised by their height and mutual distribution. Furthermore, regular irregularities can be obtained by using the appropriate tool and technological machining parameters. In this way, surfaces with similar load-bearing capacity, core volume, texture or expected hydrophobic properties can be produced by various methods. However, a basic prerequisite is the careful definition of the numerical requirements, both for the basic roughness indices and those of a complementary nature. As a rule, the strength of the adhesive joint is also lower than the strength of the adhesive itself. The strength of an adhesive joint depends on the ‘mechanical anchorage’ of the adhesive and the adhesion phenomenon on the surface. The research assumes that it is possible to induce an interaction between the geometric state of the surface and the properties of the adhesive, so as to guarantee the maximum strength of the adhesive joint. To verify this, a series of experimental tests were developed and carried out for two different adhesives characterised by different viscosities and offered bond strength. Based on the tests carried out, recommendations were made to the designers of adhesive joints, where, in addition to the height of the surface irregularities, the properties related to fluid retention and the shape of the irregularities in the valleys should be determined.

Hybrid techniques for surface treatment should ensure compliance with exterior layer state and stress requirements. The more factors which influence final treatment effects, the more difficult it is to conduct a technological process combining different treatment methods. A combination of shaping milling with finishing burnishing can provide very good smoothness and satisfactory stress conditions. However, implementation of predefined geometric surface specifications (GPS) is very difficult. This article presents the results of the effect of technological parameters of both treatments combined into a single operation on surface topography. A new surface geometry evaluation approach, combining both relative and absolute changes of isotropy and surface roughness, enabling an objective efficiency comparison of machining operations combined in a single operation, is presented.