International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

The paper presents the results of research focused on the renovation of worn surfaces. Four progressive welding technologies were used – Cold Metal Transfer, MIG Pulse, TOP-TIG and laser technology. The layers were evaluated by non-destructive tests – visual, capillary and ultrasonic methods. The layers were evaluated under dry-friction adhesive wear conditions by the Ball-On-Disc method. A Si3N4 bead was used. Analyzes confirmed the impact of the renovation method on the quality of the resulting surface.

Molds designed for high-pressure casting of aluminum are exposed to very intense thermal, mechanical but also chemical stress during their operation. This stress leads to a synergistic effect of a combination of high-temperature corrosion processes in molten metals, under real conditions associated with mechanical wear. High-temperature corrosion in the environment of liquid metals occurs in the foundry industry, when casting molten metal most often into steel molds. Repair of worn parts of molds by welding, which can be performed even after their irreversible surface degradation, is a very efficient, cost-effective and envi-ronmentally acceptable form of their maintenance, while the chemical and physical properties are welded layers if they exceed the properties of the original material.

At present, various types of steel grades are used in the production of welded structures and assemblies, resp. combinations of ferrous and non-ferrous metals. In these mutual combinations, it is necessary to know the specifics of weldability of both materials, to choose a suitable welding technology and a suitable filler material. In the experimental part, the quality of heterogeneous welded joints was verified by the GMAW method. A protective gas atmosphere of 82% Ar + 18% CO2 was used for welding (M21 – ISO 14175: 2008). The possibilities of welding and mutual combinations of austenitic stainless steel with structural non-alloy steel, structural alloyed high-strength steel with structural non-alloy steel were assessed. The quality of welds was evaluated using non-destructive and destructive tests in terms of standards: visual test STN EN ISO 17637, capillary penetration test STN EN ISO 22476-12, internal errors were evaluated using radiation tests STN EN ISO 17636-1. The destructive tests used the tensile test STN EN ISO 6892-1, the weld fracture test STN EN ISO 5173 and the Vickers hardness test STN EN ISO 6507-1, the bending impact test STN EN ISO 9016 and the metallographic analysis according to STN EN ISO 17639.

The paper presents the results of research focused on the restoration of functional areas of products by the application of PTA technology. Hardfacing layers intended for the renovation of the surfaces of aluminum alloy injection molds were evaluated. The base material was medium alloy steel X38CrMoV5-1 (H11). Three types of powder additives were applied to form the functional layers: two types based on iron, designated HSS 23 and HSS 30, and one type based on nickel, designated DEW Nibasit 625 -P. The quality of the layers was evaluated using non-destructive and destructive tests. The surface integrity of the layers was assessed by visual and capillary tests. The microstructure of the materials and its hardness were evaluated. The tribological properties of the welds were determined by the pin-on-disc method.

The paper presents the results of research aimed at determining the quality of welds in steel and aluminum alloys. Laser welding technology, fusion-pressure welding in combination with adhesive bonding were used for joining. The present research describes a new bonding technology based on the resistance welding process with a combination of adhesive bonding. Its implementation allows the joining of aluminum and steel sheets at extremely short welding times with a high concentration of energy in combination with adhesive bonding. The quality of the joints was determined on the basis of the tensile shear test according to ISO 12996.

The paper presents the results of the research focused on the determination of the quality of adhesive joints of cold rolled sheets in the automotive industry. DC05 galvanized sheet was used for joints. A progressive type of adhesive used in the automotive industry was chosen. The shear and peel strength of the adhesive joints according to Winter were determined. The strength of the joints was determined depending on the cure temperature of the adhesive. After tests, the character of fracture surfaces of adhesive joints was evaluated.

The advantages of using composite materials are currently manifested in various industries. This creates space for their even greater application in the automotive industry. Car manufacturers strive to constantly reduce the weight of the car, increasing its durability and safety at the same time. Car consumption and associated emissions are closely monitored. Composite materials therefore offer a range of properties that meet today’s automotive requirements to a large extent.