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

The paper presents the results of an investigation focused on the analysis of the wear of moulds for high-pressure casting with Al alloy. In order to repair and refurbish the mould parts of moulds for high-pressure casting of aluminium alloys, samples of experimental welds were prepared on the base material of grade 1.2343 (Dievar) of dimensions 150x130x30 mm refined to the hardness value of 44-48 HRC. A TruDisk 4002 solid-state disk laser with BEO D70 focusing optics was used for surfacing. Mat.No.1.2343 (Dievar), Mat.No.1.6356 (Dratec) and Mat.No.1.6356 (UTPA 702 and NIFIL NiCu7/Dievar) wires were used as additional material. Light microscopy technique was used to inspect the microstructures on the cross-sections of the welds. Microhardness measurements were performed with a Vickers indenter at a load of 500 g and a mutual indentation distance of 0.4 mm between the indenter impressions.

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.