The article presents the results of research on abrasive and tribocorrosion wear of boron steel. This type of steel is used in the automotive and agricultural industries for the production of tools working in soil. The main goal of the article is the evaluation of tribocorrosion and abrasive wear for hot-formed 22MnCrB5 steel and a comparison of the obtained results with test results for steel in a cold-formed state. The spinning bowl method to determine the wear of samples working in the abrasive mass was used. Furthermore, a stand developed based on the ball-on-plate system allows to determine the wear during the interaction of friction and corrosion. After the hot-forming process, 22MnCrB5 steel was three times more resistant for the abrasive wear than steel without this treatment. The average wear intensity for 22MnCrB5 untreated steel was 0.00046 g per km, while for 22MnCrB5 hot-formed steel it was 0.00014 g per km. The tribocorrosion tests show that the wear trace of hot-formed 22MnCrB5 steel was about 7.03 µm, and for cold-formed 22MnCrB5 steel a 12.11 µm trace was noticed. The hot-forming method allows to obtain the desired shape of the machine element and improves the anti-wear and anti-corrosion properties for boron steel.

Inseparable joints are widely used in machine and vehicle construction. Hybrid joints include bonding with sheet metal clinching. This combination reduces costs as well as the time of production compared to welded joints. Tests on the samples made of DC01 sheets were carried out. A case study was conducted on four research series. For each series, the shear forces of the joint were measured. The first series consisted of adhesive bonding, and the second and third series consisted of hybrid bonding, during which the sheet metal clinching joint was developed immediately after the completion of adhesive application and after full joint formation. The last test series only includes sheet metal clinching. In the series where bonding was used, the homogeneity of the prepared joints was analysed using the ultrasonic echo technique. The shear strength of the bonded joints was 476 N, whereas the shear strength of sheet metal clinching was 965 N. For the hybrid joint, the average forces were 1085 N (for the specimens in which the lap joint was made after the joint was fully cured) and 1486 N (for the specimens in which the lap joints were made immediately after the adhesive was applied). It was discovered that the clinching of the steel sheets significantly increases the strength of the joint. The stabilisation of the joint causes better crosslinking conditions. This results in an increase in the strength of the hybrid joint.

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Abstract. The paper presents technology of forming of a face gear cooperating with cylindrical worm in spiroid gear drive application for rotation table. The method is based on application of a disc tool instead application of a hob. The solution is possible after application the CNC milling machine with five axis numeric system control. The method of forming face gear proposed in this article is based on application of the disc tool with a single blade edge and CNC milling machine. The method of forming the face gear cooperation with cylindrical worm on CNC milling machine with continuous divide and the scheme of the process kinematics have been presented in the paper. IntroductionInvention of face worm gear drives with conical worm by Saari [1] was a substantial contribution. Face gear cooperating with cylindrical worm in spiroid gear drive can be cut with conical or cylindrical hob cutter [1,2,3,4]. Litvin and coworkers [5] had proposed a tilted head-cuter for forming of face gear with cylindrical worm. Grajdek [6] developed a new technique of cutting a face gear on a CNC machine. He used the 4-axis vertical CNC milling machining incorporate a rotary table and a NC spindle. The generations are performed by a tilted tool edge with straight line profiles of blades.The authors of the paper [5] point out to big problems with sharpening hobbing cutters with small radius blades used for forming face gear and hob scale error that are transferred onto the gear. There is also a possibility of cutting the face gear with the use of a disc tool with a single blade tool [7,8,9]. For generation face gear used the 5-axis vertical CNC milling machine incorporate a rotary table and a NC spindle. The generations are performed by a tilted tool edge with straight line profiles of blades. Due to addition two rotational axes in 5-axis machining enables forming face gear and taken high surface quality. For numerically controlled milling machine a face gear can be shaped with different front lines of teeth [7]. While notching the teeth, workgroups of machine performs movements at a constant speed, the tracks are rectilinear or rotary (NC rotary table, spindle tool).Face gear cooperating with cylindrical worm in spiroid gear drive may have different type of involute teeth line used (elongated, shortened) with a modification of the teeth line and profile, in order to avoid edge contacts. All those involute teeth lines in face gear variations can be cut with the use of a disc tool on CNC machine tools.The Company Tool Works in Illinois -USA manufacture different types of spiroid gears. Figure 1 illustrates the idea of construction of a spiroid gear drive type duplex with two face gears cooperation with cylindrical worm application for rotation table.

The paper presents the scope of applicability and the usefulness of the method of predicting crystalline structure of castings using a commercially available system called Calcosoft CAFE. The influence of individual values of the parameters of the thermal model and the model predicting the structure (phenomenon of nucleation and crystal growth), and the method of interpretation of the results were identified. In simulation studies, it is important to use reliable and validated material database, under appropriate conditions. It is necessary to predict the properties of castings with a comprehensive, new and practical approach to modelling the formation of phase components of structure in terms of both macroscale and microscale phenomena (Multiscale and Multiphysics). Therefore, in this paper, the experimental-simulation validation of the CAFE code was undertaken. The tests were carried out on castings solidifying under various heat transfer conditions controlled by mould materials such as: a homogenous mould made of moulding sand, moulding sand with chill, and mould made of insulating mass with chill. These conditions directly influence the structure formation. The method of validation of the structure was determined in terms of its three parameters, i.e., the degree of refinement of the crystals, the location of the columnar-to-equiaxed transition zone—CET and the angle of the crystals. The above tests enabled to extend the content of databases, which often lack the necessary values of parameters used in modelling, e.g., crystallization of a specific alloy under given conditions (sand casting, chills or laser surface treatment). On this basis, the basics of correlating the simulation results on a micro- and macroscale were generalized, the limits of the application of individual parameters (mould, alloy materials) and their impact on the structure formation were determined. It resulted in the extension of the database for simulation calculations.

Abstract. The paper presents the investigations of selected chemical and mechanical properties as well as macro-and microstructure of materials formed using thermal drilling process (Flow drill). The aim of this study was to determine the microstructure of the coatings produced using laser cladding with powder technology. The coatings were produced on the lowcarbon steel using 1 kW disc laser. After modification of surface, the thermal drilling process was applied. To produce all coatings, the pure copper powder was used. In this study the laser power equal of 500, 700 and 900 W were used. The microstructure, chemical composition (EDS) and microhardness were investigation. It was found that the surface modification of low carbon steel and next conducted thermal drilling process caused change the surface properties on the hole flange. It was found that surface modification of steel using laser cladding with cooper powder and next Flow drill process contributes to the change in microhardness and chemical composition on hole flange.

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The paper presents the study results of Fe-B coatings produced on C45 steel using laser cladding with powder technology. For this purpose, 5-axis CNC laser machining center equipped with Yb:YAG disk laser with a power rating of 1 kW and three streams powder feeding system. The powder that was used to produce Fe-B coatings was subsequently modified by the particles of boron carbide B 4 C and Si particles. The resulting powder mixture to the particles included 25 wt % respectively 20% B 4 C, 5% Si. During these studies a laser beam power of 600 W and variable scanning speed 600 mm/min, 800 mm/min and 1000 mm/min were used. Thickness and microhardness of coatings were investigated and relationship between these properties and microstructure of the applied production parameters were described. The microstructure of producing coatings was characterized by dendritic shape. It was found that boron carbide particles and silicon particles have significant influence on increase the microhardness of produced coatings. Coatings were produced using the prepared powder mixture allowed to obtain more than twice greater microhardness than in case of coatings produced using only the Fe-B powder. Phase composition was examined by XRD. Phases of Fe 3 B, Fe 5 Si 3 , Fe 2 Si and SiB 6 were identified. The influence of B 4 C and Si particles in the mixture of powder on the corrosion resistance of produced coatings were discussed. It was found gradual reduction of corrosion resistance with decreasing scanning speed of laser beam. Less scanning speed result in less intense interaction of laser beam on the material. As a result of this, the remelting degree of powder material with steel substrate was smaller. The surface condition after corrosion tests were examined using a scanning electron microscope. This paper also shows a calculation related to the power density of the laser beam, interaction time of beam on material and fluence.