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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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

This paper aims at working out an innovative technology of aircraft brackets with a rib of a triangular outline manufacturing from magnesium alloy AZ31 based on forging process.

Theoretical analysis of the assumed forming process of brackets with a rib of a triangular outline was made on the basis of computer simulations in software Deform 3D, basing on finite-element method. Research works were conducted for a magnesium plate from magnesium AZ31 alloy. Considering calculations, the scope of technological parameters guaranteeing the process proper course and good quality of the product was determined. Theoretical results were verified using a three-slide forging press.

The experiment’s results confirmed the effectiveness of the worked-out technology and the rightness of its application at manufacturing of brackets from non-ferrous metals used in the aircraft industry.

The main aim of the worked-out method is manufacturing of aircraft brackets from light metals alloys, e.g. magnesium alloys. This technology can be applied for plastic forming of flat parts with ribs of a triangular outline. Manufacturing of aircraft brackets, basing on that worked out by the author’s technology, will allow for the improvement of products’ quality and reduction of their manufacturing costs.

The originality of this paper is based on the presentation of a new, innovative manufacturing technology of brackets with a rib of a triangular outline. The presented method is a unique one at a national (Poland) and global scale, and its assumptions underwent patent protection.

The purpose of this research is working out of a new forming technology of flat parts with ribs from magnesium alloys with the application of a three-slide forging press (TSFP) for the aircraft industry.

New possibilities of forming aviation parts with ribs gives the application of a prototype TSFP. This press consists of three moveable tools and has wider technological possibilities than typical forging machines. It was assumed that this machine (press) application would allow for obtaining ribbed flat forgings from magnesium alloys of good functional and resistance qualities. A characteristic feature of such forgings forming is the working movement of two side tools, which upset the billet in the form of a plate; the result of their action is forming of one or more ribs in the plane central part. It is possible to use the upper punch to form appropriate rib outline. Theoretical research works based on simulations by means of finite element method were conducted for three cases of the process: semi-free forging of parts with one rib, semi-free forming of forgings with two ribs and forging in closed impression of parts with one rib of triangular outline. The first experimental tests were made on a TSFP for the variant of semi-free forging of parts with one rib.

Research results show that there exists the possibility of realization of forming process of parts with ribs according to the conception assumed by the authors. Positive results of theoretical analyses justify the purposefulness of conducting experimental verification for the proposed theoretical solutions of the forging processes of parts with one rib of triangular outline and with two ribs.

Production of flat parts with ribs from magnesium alloys basing on the worked out by the authors’ technology will allow for improving functional and mechanical properties of parts and for lowering their manufacturing costs. At present, such aviation parts are imported to Poland in the form of casts, which are expensive and not always fulfill the requirements. Additionally, large amount of machining at manufacturing of this type of parts generate larger price at their production.

Forging technology of parts with ribs in a TSFP is unique on a world scale. The advantages of this technology are the process material savings and better resistance properties of the formed forgings with ribs than parts obtained in a traditional way.

The purpose of research was to work out manufacturing technology of plane rim from 2618A aluminium alloy based on hammer forging process.

It was assumed that the manufacturing process consists of die hammer forging and machining. The first stage of the research works was based on designing of the forging process and on numerical simulations in which finite element method was used. On the basis of calculations results, analysis of deformation parameters in the drop forging was made and the rightness of the worked out technology was verified. The second stage of the research works concerned experiments conducted in industrial conditions. Forging dies were constructed and the forging process of a series of drop forgings was carried out. Next machining was done to obtain finished parts.

The conducted research works on the forging process on hammer of the rim drop forging from 2618A aluminium alloy showed that the application of this technology allows for obtaining the product of good quality. Manufactured rims were destined for exploitative research works, aiming at getting certificate that would allow for their implementation in planes.

The rim is being prepared for implementation in small planes of considerably large wheels load.

The presented hammer forging method of plane rim has not been used so far. In the case of applying the rims in planes building, not only industrial plants with large forging presses but also forgeries with die hammers will be able to produce these parts.

The purpose of the present paper is to develop a new technology for producing magnesium alloy twin-rib aircraft brackets by the forging method.

An overall description of magnesium alloys is given, with particular emphasis placed on magnesium wrought alloys that are used in the aircraft industry. Methods for producing ribbed brackets are discussed and the location of these parts in aircraft structure is described. The forging process for producing AZ31 magnesium alloy twin-rib brackets was modelled numerically, and selected results of the simulations performed are presented. The simulation results were then verified under laboratory conditions using a three-slide forging press equipped with three movable working tools. It was assumed that the use of this machine would allow for obtaining twin-rib aircraft brackets with improved both functional and strength properties compared to the production methods used so far.

The results demonstrate that the method developed by the present authors permits the production of twin-rib brackets. Positive theoretical results and preliminary experimental results prove that it is justified that the research on magnesium alloys used in the aircraft industry be continued.

The production of twin-rib aircraft brackets from magnesium alloys by the technology developed by the present authors would lead to enhanced product quality with simultaneous reduction in production costs (reduced labour costs and material consumption as well as increased process efficiency). At present, magnesium alloy aircraft parts, mainly obtained from semi-finished products imported to Poland, are produced by casting and machining methods. They exhibit, however, much worse properties than elements produced by metal forming methods. In addition to that, the application of machining in the production of these part leads to higher production costs.

The originality of this study stems from the presentation of an innovative metal forming technology for producing twin-rib brackets. This method is unique on a global scale, and its basic assumptions have been granted patent protection. Also, the originality of the study stems from the fact that brackets are made from magnesium alloys, as these light metals are considered the future of structural materials used in the aircraft industry. Given the above, the research on developing the technology for producing parts made from these alloys using a three-slide press is justified.