Review of Magnesium Wheel Types and Methods of Their Manufacture.

This article provides a detailed review of the types of magnesium wheels available in the industry and the current methods of the wheels' production. The past several years have seen a significant development of magnesium-based lightweight alloys employed as a structural material for modern light vehicles. Magnesium alloys are characterized by their low density while maintaining good mechanical properties. The use of these alloys in the industry enables vehicles' weight reduction while increasing their technical parameters. The first part of the article presents the unique properties of magnesium alloys that determine the application of this material for lightweight vehicle wheels. The advantages of using magnesium wheels over aluminum wheels are also presented. Next, a classification of the types of magnesium wheels was made in regard to their construction, applications, and manufacturing methods. At present, magnesium wheels by construction can be classified according to their geometry as single parts or assembled parts. In reference to geometry, wheels can have different shapes: classic, multi-spoke, with holes, or with frames. Depending on the geometry used, magnesium wheels can have different parameters, such as their mounting hole spacing, wheel diameters, or rim width. Considering the applications in various industries, main distinctions can be made between magnesium wheels for automobiles, motorcycles, bicycles, and wheelchairs. Magnesium wheels can also be categorized in regards to the manufacturing methods: casting, machining, forging, and hybrid manufacturing. The second part of the article focuses on the analysis of magnesium alloy wheel-manufacturing technologies used in the industry and developed by research centers. This article discusses these manufacturing technologies in detail and indicates prospective directions for further development.

Investigation of a New Screw Press Forming Process for Manufacturing Connectors from ZK60 Magnesium Alloy Preforms.

This article discusses a new technology of forming connector forgings from ZK60 magnesium alloy preforms by die forging on a screw press. The purpose of the study was to evaluate the feasibility of using preforms cast from the ZK60 magnesium alloy to forge a connector forging with improved mechanical properties compared to those obtained by casting. It also aimed to establish whether this new forging method has the potential for replacing the multi-stage forging process conducted on hydraulic presses used for high-strength Mg alloys. A numerical analysis of the proposed approach was performed by the finite element method, applying the popular DEFORM computer software for simulating forming processes. The numerical results confirmed that the developed method produces parts with the desired shape. The numerical results also provided information regarding the behavior of the workpiece's material and the screw press forging process, including the distributions of strains and temperatures, the Cockcroft-Latham damage criterion, and energy required to form connector forgings. The proposed screw press forging process for producing ZK60 alloy connectors from cast preforms was verified by experimental tests. The connector forgings produced from the ZK60 magnesium alloy were then subjected to qualitative tests.

The New Technology of Die Forging of Automotive Connecting Rods from EN AB-71100 Aluminium Alloy Cast Preforms.

This article presents a new technology for forming automotive connecting rod forgings by means of die forging from cast performs from EN AB-71100 (EN AB-AlZn10Si8Mg) aluminum alloy. A premise was made that the production process would be carried out on forging presses. The process of forming connecting rod forgings was analyzed considering different deformation rates related to the type of machine used: a crank press and a screw press. The billet in the form of in-house designed, shaped preforms cast into sand molds with two variants of geometry was used in the process. The numerical analysis of the new process was carried out on the basis of the finite element method using Deform 3D, the simulation software for metal forming. The simulations were conducted in the spatial deformation conditions, considering the full thermomechanical analysis. Based on the simulations, certain important findings concerning the novel process were acquired, including the distribution of stress, deformation, temperatures, cracking criterion and energy parameters. The results of numerical tests confirmed the possibility of producing defect-free forgings of connecting rods from EN AB-71100 aluminum alloy on forging presses by means of the proposed technology. The proposed process of forging using crank and screw presses was verified in the course of tests conducted in industrial conditions. The properly formed connecting rod forgings were subjected to quality tests in terms of their structure and mechanical properties.

The Analysis of Deformability, Structure and Properties of AZ61 Cast Magnesium Alloy in a New Hammer Forging Process for Aircraft Mounts.

This article presents the analysis of the deformability, structure and properties of the AZ61 cast magnesium alloy on the example of a new forging process of aircraft mount forgings. It was assumed that their production process would be based on drop forging on a die hammer. Two geometries of preforms, differing in forging degree, were used as the billet for the forging process. It was assumed that using a cast, unformed preform positively affects the deformability of hard-deformable magnesium alloys and flow kinematics during their forging and reduces the number of operations necessary to obtain the correct product. Numerical analysis of the proposed new technology was carried out using DEFORM 3D v.11, a commercial program dedicated to analyzing metal forming processes. The simulations were performed in the conditions of spatial strain, considering the full thermomechanical analysis. The obtained results of numerical tests confirmed the possibility of forming the forgings of aviation mounts from the AZ61 cast magnesium alloy with the proposed technology. They also allowed us to obtain information about the kinematics of the material flow during forming and process parameters, such as strain intensity distribution, temperatures, Cockcroft-Latham criterion and forming energy. The proposed forging process on a die hammer was verified in industrial conditions. The manufactured forgings of aircraft mounts made of AZ61 magnesium alloy were subjected to qualitative tests in terms of their structure, conductivity and mechanical properties.

Analysis of the New Forming Process of Medical Screws with a Cylindrical Head of 316 LVM Steel.

The originality of this paper lies in the presentation of a new, innovative method for manufacturing medical screws with a cylindrical head of 316 LVM. This method is unique on a global scale, and its assumptions have been granted patent protection. The paper presents selected results of theoretical and experimental research on the developed process of forming of medical screws based on new technology. In the first part of the study a review of the types of screws used in the medical industry is made and the previous methods of their manufacture are described. The second part of the paper presents the assumptions and analysis of the elaborated process of metal forming of medical screws with a cylindrical head and ring thread made of 316 LVM austenitic steel. The theoretical analysis of the new process of forming a screw selected for testing was performed on the basis of numerical simulations. The experimental verification of the proposed theoretical solutions was carried out on the basis of laboratory tests, industrial research and qualitative research. The positive results obtained from computer simulations and experiments confirmed the effectiveness of the developed technology and the validity of its use in future in industrial practice.

The effect of pre-emptive analgesia on the level of postoperative pain in women undergoing surgery for breast neoplasm.

AIM OF THE STUDY: Dynamic development of research on pain has resulted in the formulation of the concept of pre-emptive analgesia, which involves administration of analgesics before the first pain-producing stimulus appears. It is meant to prevent increased sensitivity to pain in the postoperative period. The aim of this study was to assess the possibilities of modifying the intensity of postoperative pain evaluated with the visual analogue scale (VAS) in patients after surgical treatment for breast neoplasm offered by pre-emptive analgesia. MATERIAL AND METHODS: The intensity of postoperative pain was measured immediately after the surgery as well as 6, 12, 18, and 24 hours later in 100 women who had undergone surgery for breast tumour. The correlation between experienced pain and the type of analgesic administered pre-emptively, including metamizole, tramadol, ketoprofen, and placebo was examined. The effect of other correlates such as the extensiveness of surgery, systolic and diastolic blood pressure, and heart rate on the level of experienced pain as well as the usefulness of physiological parameters for its assessment were also analysed. RESULTS: The conducted study demonstrated the effectiveness of tramadol (p = 0.004) and ketoprofen (p = 0.039) administered half an hour before the beginning of surgery, but there was no similar effect in the case of metamizole (p = 1.0). A positive correlation was observed between the level of experienced pain and blood pressure values (p < 0.001). Heart rate does not seem to be significantly linked with the intensity of experienced pain (p = 0.157).