The paper presents the theoretical and technological aspects of forming magnesium alloy parts for aircraft and automotive applications. The main applications of magnesium alloys in the aircraft and automotive industries are discussed. In addition, the forging technology for magnesium alloys is...

The AZ31 alloy is one of the most popular magnesium alloys with aluminum. Due to its low mass density and good mechanical properties, this structural material offers considerable potential for the aircraft manufacturing industry. The AZ31 alloy is used in the aircraft industry to produce flat parts with ribs, such as brackets. The paper presents the results of a quantitative study on the microstructure and mechanical properties of AZ31 alloy aircraft brackets produced by a new technology of semi-open die forging. The experimental tests of forming these flat ribbed parts were conducted at a temperature of 410°C using a prototype forging press equipped with three moving tools. The microstructure and mechanical properties of the AZ31 alloy were examined at delivery and after hot forging

The purpose of this paper is to determine time-to-ignition of magnesium alloy chips and the ignition-preceding stages as well as to examine chip morphology. The tests were conducted according to the following pattern: directly after a milling operation, after ignition using a special test stand located outside the machine tool and after intensive oxidation which prevented ignition. Milling is a machining process widely used in the manufacturing of various parts that are applied, e.g. in the aircraft industry. Milling is used for both roughing and finishing machining. In the dry machining of magnesium alloys, spontaneous ignition can occur; therefore, the analysis of chip temperature in the cutting area is of great significance. Additionally, time-to-ignition and chip morphology are crucial when considering the safety of magnesium alloy machining processes. The experimental results demonstrate the effect of parameters of the milling process on time-to-ignition of chips made of magnesium alloys AZ31 and AZ91HP. The experiments also involved examining the morphology of a selection of chips produced at the maximum cutting velocity vc and feed per tooth fz. In addition, we analysed the morphology of both ignition products and chips subjected to high temperature where ignition did not occur. Based on the time-to-ignition and chip morphology results, it is possible to indicate both safety levels in machining and the efficient range of parameters in the milling of aircraft parts made of magnesium alloys. The paper presents a new approach to assessing safety in milling operations. The results of the tests of chip flammability (time-to-ignition) which were run at a special test stand placed outside the machine tool enabled determination of both safety and efficiency range of the milling process.

Purpose: The purpose of this study is to report results of the qualitative assessment of AZ31 aircraft brackets with a triangular rib produced by a new forging method with respect to their structure and mechanical properties. Design/methodology/approach: The paper reports the results of qualitative tests for AZ31 magnesium alloy aircraft brackets with a triangular rib produced by a new forging method. These ribbed parts were formed on a forging press equipped with three moving tools. The produced aircraft brackets were subjected to qualitative tests. Their cross-sectional microstructure was examined using the light-field technique. The mechanical properties of ribbed parts were determined in a static tensile test and by hardness measurements on the surface of the part. The following variables were determined: tensile strength Rm, yield strength R0.2, elongation A5 and hardness. Findings: The results of qualitative tests provide significant information about produced aircraft brackets with a triangular rib, i.e. microstructure in three key regions of brackets and their mechanical properties. Practical implications: The method will enable producing magnesium alloy aircraft brackets with a triangular rib. The application of the method for aircraft brackets developed by the authors of this paper will result in higher product quality and reduced production costs. The paper demonstrates the practical application of this technique by presenting a finished aircraft bracket and the results of complete qualitative tests. Originality/value: The originality of this paper lies in the presentation of a new, innovative method for manufacturing aircraft brackets with a triangular rib. This method is unique on a global scale, and its assumptions have been granted patent protection.

Purpose: The aim of this study is to develop a die forging process for producing aircraft components made of magnesium alloy AZ61A using a screw press. Design/methodology/approach: The proposed forging technique has been developed based on the results of a numerical and experimental research. The required forging temperature has been determined by upsetting cylindrical specimens on a screw press to examine both plasticity of the alloy and the quality of its microstructure. The next stage involved performing numerical simulations of the designed forging processes for producing forgings of a door handle and a bracket, both made of magnesium alloy AZ61A. The finite element method based on simulation programme, Deform 3D has been used for numerical modelling. The numerical results revealed that the forgings are free from material overheating and shape defects. In addition to this, the results have also helped determine the regions that are the most prone to cracking. The final stage of the research involved performing forging tests on a screw press under industrial conditions. The forgings of door handles and brackets were made, and then these were tested for their mechanical and structural properties. The results served as a basis for assessing both the viability of the designed technique and the quality of the produced parts. Findings: The experimental results demonstrate that aircraft components made of magnesium alloy AZ61A can be produced by die forging on screw presses. The results have been used to determine the fundamental parameters of the process such as the optimum forging temperature, the method of tool heating, the way of cooling parts after the forging process, and the method of thermal treatment. The results of the mechanical and structural tests confirm that the products meet the required quality standards. Practical implications: The developed forging technique for alloy AZ61A has been implemented by the forging plant ZOP Co. Ltd in Swidnik (Poland), which specializes in the manufacturing of aircraft components made of non-ferrous metal alloys. Originality/value: Currently, the global tendency is to forge magnesium alloys (including alloy AZ61A) on free hydraulic presses using expensive die-heating systems. For this reason, the production efficiency of such forging processes is low, while the manufacturing costs are high. The proposed forging technique for alloy AZ61A is an innovative method for producing forgings using relatively fast and efficient machines (screw presses). The proposed forging method can be implemented by forging plants equipped with standard stocks of tools, which increases the range of potential manufacturers of magnesium alloy products. In addition, this technology is highly efficient and ensures reduced manufacturing costs.