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Influence of heat treatment on the corrosion resistance of the aluminum-copper (Al-Cu) coating on the aluminum substrate was investigated. The coating was produced by the electrical discharge alloying (EDA) method. The surface and microstructure of the specimens were observed by a scanning electron microscope (SEM). The phase analysis of the composite materials by X-ray diffraction (XRD) and energy-dispersive spectroscopy (EDS) indicated that intermetallic compounds (i.e., CuAl2 and Cu9Al4) were formed through reactions between Al and Cu. during the EDA process. A significant increase in the hardness of the Al-Cu coating was affected by the improvement of the alloy structure. The heat treatment of materials was carried out at 400 °C or 600 °C in the air atmosphere. A corrosion test of materials was carried out by using electrochemical methods. The corrosive environment was acidic chloride solution. After heat treatment at 400 °C the mechanical properties of the Al/Cu alloy increased significantly and the oxide layer protect of the alloy surface against corrosion. However, after heat treatment at elevated temperature, i.e., 600 °C it was found that the (Al2O3)ads and (CuO)ads coatings were destroyed. The mechanical properties of the Al/Cu alloy decreased, and its surface has undergone deep electrochemical corrosion.

The paper presents the production problems related to casting using precision casting methods. The essential adverse effect of the casting process is the presence of burrs understood as oversize material necessary to remove the next finishing operations. In addition, the surfaces of the cast often characterized by a porous structure. One of the methods to improve the smoothness of the area proposed by the authors is the use of vibro-abrasive finishing. This type of treatment is widely used in the treatment of finishing small objects as well as complex shapes. Objects in the form of casting in the first step was treated with aggressive deburring polyester matrix abrasive media. The second stage was polishing, with using smoothing porcelain media. The study evaluated the effect of vibro-abrasive machining typical cast on the basic parameters of the geometric structure of the surface. Observations using optical microscope Nicon Eclipse MA 200 compared changes in surface microstructure and the effect of deburring. Clearly we can say that vibro-abrasive machining an effective way of reducing the size of burrs, smoothing and lightening the surface of objects made by casting.

The authors have presented a new method of electro-discharge mechanical dressing of ultra-hard abrasive tools with metal bonds in which brush electrodes were used. This kind of machining is denoted as EDMD (electro-discharge mechanical dressing) and combines features of electro-discharge machining with mechanical treatment so that thin layers of the bond are removed. Moreover, the brush electrode offers the additional possibility of introducing the advantageous (having the anchorage of the abrasive grains in mind) state of compressive stress and strain hardening of the outer layer of the bond.

This article considers effects of local heat transfer taking place insteel cutting by abrasive water jet machining (AWJM). The influence of temperature changes during AWJM has not been investigated thoroughly. Most studies on AWJM suggest that thermal energy has little or no effect on the material cut. This study focused on the analysis of the material microstructure and indentation microhardness in the jet impact zone and the adjacent area. The structure features revealed through optical metallography and scanning microscopy suggest local temperature changes caused by the impact of the abrasive water jet against the workpiece surface. From the microscopic examinationand hardness tests, it is clear that, during the process, large amounts of energy were transferred locally. The mechanical stress produced by the water jet led to plastic deformation at and near the surface. This was accompanied by the generation and transfer of large amounts of heat resulting in a local rise in temperature to 450 °C or higher.