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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.

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.

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The article presents an example of finishing treatment for aluminum alloys with the use of vibration machining, with loose abrasive media in a closed tumbler. For the analysis of selected properties of the surface layer prepared flat samples of aluminum alloy PA6/2017 in the state after recrystallization. The samples in the first stage were subjected to a treatment of deburring using ceramic media. In a second step polishing process performed with a strengthening metal media. In addition, for comparative purposes was considered. only the case of metal polishing. The prepared samples were subjected to hardness tests and a tangential tensile test. As a result of finishing with vibratory machining, it was possible to remove burrs, flash, rounding sharp edges, smoothing and lightening the surface of objects made. The basic parameters of the surface geometry were obtained using the Talysurf CCI Lite -Taylor Hobson optical profiler. As a result of the tests it can be stated that the greatest reduction of surface roughness and mass loss occurs in the first minutes of the process. Mechanical tests have shown that the most advantageous high values of tensile strength and hardness are obtained with two-stage vibration treatment, -combination of deburring and polishing. Moreover the use of metal media resulted in the strengthening of the surface by pressure deburring with metal media.