The research aims to improve performance of high-accuracy hole-making in hybrid stacks. The stacks consist of carbon fiber reinforced plastic and Titanium and Aluminum alloys. Holes were made with Atlas Copco PFD-1500, a pneumatic drilling machine with automatic tool feeding. A MAPAL hard-alloy six-toothed reamer with MQL channels was used as a cutting tool. Hole diameters were controlled using Carl Zeiss CONTURA G2. Cutting parameters' variation ranges were identified and the experiment was designed in Statistica 6. The experiment design involves two factors (cutting speed, feed) and an additional block factor describing a reaming allowance. As a result, multi-factor regression analysis models were developed. They describe the effects of cutting parameters on the hole accuracy in hybrid stacks. The cutting parameters were optimized and recommendations were given.

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The article aims to establish the effect of preventive deformation on the accuracy of aircraft parts made from the thermally hardened aluminium alloy 1933T2, after blasting hardening. Determination of the impact of preventive deformation was carried out by analysing structural parts of the "wall" type produced using various technological sequences. Sample 1 was produced using a standard manufacturing sequence: milling – blasting hardening – blasting correction. Sample 2 was produced as follows: milling – preventive deformation – hardening – blasting correction. The deformation of the samples was determined at checkpoints by deviations from flatness based on bending deflections. In sample 2, preventive deformation was performed on its ridges by a rolling device. The calculation of the technological parameters of the rolling device was conducted following the principle of superposition of individual operations, such as rolling and blasting hardening. The definition of the parameters of preventive deformation of sample 2 was based on the results ob tained for sample 1. It was established that, for both samples, the deviation from flatness after milling comprised 2.5 mm. The maximum deviation of sample 1 (without preventive deformation) after blasting hardening was 2.6 mm under a high degree of surface saturation. The maximum deviation of sample 2 (with preventive deformation) after blasting hardening did not exceed 0.4 mm, which corresponds to the acceptable deviation of such structural parts. Thus, the inclusion of the preventive deformation stage in the manufacturing process, with consideration of the deviations resulting from the milling stage, allows minimisation of deviations from the required form after blasting hardening. An analysis of the obtained re[1]sults confirmed that preventive deformation of structural parts reduces distortions after blasting hardening. Therefore, it is advisable to use the following manufacturing sequence: preventive deformation → hardening by a blasting method → correction by a blasting method.

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