РОЗРАХУНОК ЗУСИЛЬ ФОРМОУТВОРЕННЯ ПАНЕЛЕЙ ПОВІТРЯНОГО СУДНА ПРИ ПОСЛІДОВНОМУ ВІЛЬНОМУ ГНУТТІ НА СПЕЦІАЛІЗОВАНОМУ ОБЛАДНАННІ

Author(s):  
С. А. Бычков ◽  
Б. В. Лупкин ◽  
А. А. Павленко ◽  
Ю. А. Корольков

The design of a modern aircraft provides for a high degree of panelizing of outline elements which can reach up to 80...85%. This allows to increase strength and rigidity with a simultaneous reduction in weight and improved flight performance of the product by reducing the number of fasteners and riveted seams. Also, the improvement of parameters occurs due to the use of high-strength aluminum and other alloys. However, the manufacture of such panels is time consuming and requires special equipment. At a time when technologies and equipment for the manufacture of single-curvature panels are fairly well developed, it is still difficult to manufacture panels with variable twist (washout) of cross-sections on the existing universal equipment with the prescribed accuracy. Basically, for the manufacture of such panels free bending, requiring a large number of finishing works is used. The use of universal equipment such as Sheet Stretch Forming Press is also not sufficiently effective, since the form die produced individually for each part and has a high price. To overcome the existing shortcomings it is proposed to use a multi-point controlled roller punch and a die, the shape of which is set by the CNC device according to information from a digital mock-up. A design diagram for determining the acting forces on the rollers of a multipoint punch during the sequential formation of the workpiece was developed. A method for calculating the technological parameters of the panel forming process is presented. It allows to determine, in particular, the total force required to feed the rollers of multi-point punch, the values of the transverse compensation angle of the rollers of multi-point punch and the number of deformation strokes. The initial data for the implementation of the process are determined, the scheme of the process of forming a panel with variable twist is described. An example of solving the problem of determining the technological parameters of the process of forming a panel on the proposed equipment by the proposed method is given.

2015 ◽  
Vol 799-800 ◽  
pp. 439-442
Author(s):  
Ya Zhang ◽  
Dae Hwan Yoon ◽  
Dong Won Jung

Roll forming is a highly useful and important forming technique for sheet metal. As an economic profile product, roll forming products are widely used in transportation, engineering machinery, and civil construction because of their uniform sections, high strength, and low energy consumption[1]. Roll forming is a rapid processing operation used for transforming flat sheets of material into useful profiled sections. However, a lot of components used in the automobile, railway cars, ship construction, and building industries have variable cross sections. Therefore, flexible roll forming was developed recently to produce variable cross section profiles.


2020 ◽  
Vol 1 (154) ◽  
pp. 67-70
Author(s):  
N. Tsapko

The article analyzes the possibility of developing custom binders with a set of set properties. Particular attention is paid to the development of radiation-resistant barium-containing cements based on aluminates and barium silicates. In order to normalize the radiation situation in Ukraine, it is urgent to develop structural materials with specified high protective properties against the effects of radiation, a high degree of biological protection in combination with high strength and fire resistance. The main components of the technological parameters of synthesis of the presented cements are determined. Test results of physical and mechanical properties of refractory radiation resistant cements are presented and general recommendations on the scope of the developed binder materials are given. It is determined that the resulting refractory cement can be used as a bond in the manufacture of special concretes and materials that have high protective properties while exposed to high temperatures and radiation. Thermal stability of concrete based on silicate alumobarium cement with different fillers was determined (cooling of the samples was carried out in air). As a result of the tests, it was found that all concrete specimens withstood more than 20 cycles (1000 ° C - air), while maintaining more than 80 % of the initial strength. These results confirm the known pattern: the higher the material density, the greater the material's ability to absorb radiation. Thus, the obtained data allow us to conclude that concrete based on silicate alumobarium cement have high absorption rates of brake radiation, which is more than 1.5 times higher than currently used concrete based on Portland cement. Therefore, it can be concluded that the concretes obtained are radiation resistant, with a high degree of attenuation of gamma rays and can be recommended as protective materials. Keywords: cement, composition, synthesis parameters, radiation resistance, property, strength


Author(s):  
O.V. Savvova ◽  
S.A. Ryabinin ◽  
E.A. Svitlichniy ◽  
G.K. Voronov ◽  
A.I. Fesenko

Advanced methods for obtaining high-strength glass-ceramic materials based on lithium aluminum silicate glass for glass and ceramic technologies are identified. Were analyzed  forming methods: pressing, thermoplastic molding and slip casting with the definition the advantages and disadvantages of in each of them. The choice of the base LAS system is substantiated and model lithium-aluminum-silicate glasses and glass-ceramic materials based on β-spodumene are synthesized by the methods of pressing, slip casting and thermoplastic molding. The features of the formation of glass-ceramic materials using various technologies are investigated. Technological parameters were established for pressing: molding powder with a fraction size from 63 to 125 μm − 70 vol. %, from 25 to 63 microns − 15 vol. %, less 25 microns − 15 vol. %, xanthan gum solution in an amount of 10 wt. %; for slip casting: slip specific weight − γ = 1852 kg/m3, pH = 9.90; for the thermoplastic formation: paraffin − 15 wt. %, beeswax − 5 wt. %, oleic acid − 1 wt. %. It has been established that the determining influence on the mechanical properties of the developed glass-ceramic materials has the character of their micro- and macrostructures. It has been established that, for the studied glass-ceramic materials, an increase in porosity and pore size significantly affects the magnitude of their compressive strength. Glass-ceramic materials obtained by wet pressing and slip technology can be recommended as the most technologically advanced in creating composite armor elements and promising in the development of high-strength glass-ceramic materials for the local protection of special equipment and technology. Composite structural materials obtained by thermoplastic processing can be used to create high-strength parts for precision mechanisms and instruments, which are subject to stringent requirements for mechanical strength.


Alloy Digest ◽  
1985 ◽  
Vol 34 (1) ◽  

Abstract UNILOY 13-8 has high strength, ductility and toughness in large cross sections in both longitudinal and transverse directions. The alloy has excellent mechanical property uniformity; this is the result of a well-balanced chemical composition. Because of its excellent general corrosion resistance (nearly equal to AISI Type 304 stainless steel) and its high degree of resistance to stress-corrosion cracking, it is used in a variety of environments. Typical uses are aircraft structural components, shafts, valve parts and fittings. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on low and high temperature performance, and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: SS-457. Producer or source: Cytemp Cyclops.


Author(s):  
O. Yu. Kichigina

At production of stainless steel expensive alloying elements, containing nickel, are used. To decrease the steel cost, substitution of nickel during steel alloying process by its oxides is an actual task. Results of analysis of thermodynamic and experimental studies of nickel reducing from its oxide presented, as well as methods of nickel oxide obtaining at manganese bearing complex raw materials enrichment and practice of its application during steel alloying. Technology of comprehensive processing of complex manganese-containing raw materials considered, including leaching and selective extraction out of the solution valuable components: manganese, nickel, iron, cobalt and copper. Based on theoretical and experiment studies, a possibility of substitution of metal nickel by concentrates, obtained as a result of hydrometallurgical enrichment, was confirmed. Optimal technological parameters, ensuring high degree of nickel recovery out of the initial raw materials were determined. It was established, that for direct steel alloying it is reasonable to add into the charge pellets, consisting of nickel concentrate and coke fines, that enables to reach the through nickel recovery at a level of 90%. The proposed method of alloying steel by nickel gives a possibility to decrease considerably steel cost at the expense of application of nickel concentrate, obtained out of tails of hydrometallurgical enrichment of manganese-bearing raw materials, which is much cheaper comparing with the metal nickel.


Alloy Digest ◽  
1969 ◽  
Vol 18 (9) ◽  

Abstract IN-102 is a nickel-chromium-iron alloy designed for long service at temperatures up to 1300 F. It combines high strength and high ductility at the elevated temperatures with a high degree of structural stability. It is used for aerospace, power and steam turbine components. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as creep. It also includes information on low and high temperature performance, and corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: Ni-147. Producer or source: International Nickel Company Inc..


2021 ◽  
Vol 11 (5) ◽  
pp. 2142
Author(s):  
Trung-Kien Le ◽  
Tuan-Anh Bui

Motorbike shock absorbers made with a closed die employ a tube-forming process that is more sensitive than that of a solid billet, because the tube is usually too thin-walled to conserve material. During tube forming, defects such as folding and cracking occur due to unstable tube forming and abnormal material flow. It is therefore essential to understand the relationship between the appearance of defects and the number of forming steps to optimize technological parameters. Based on both finite element method (FEM) simulations and microstructural observations, we demonstrate the important role of the number and methodology of the forming steps on the material flow, defects, and metal fiber anisotropy of motorbike shock absorbers formed from a thin-walled tube. We find limits of the thickness and height ratios of the tube that must be held in order to avoid defects. Our study provides an important guide to workpiece and processing design that can improve the forming quality of products using tube forming.


Procedia CIRP ◽  
2014 ◽  
Vol 18 ◽  
pp. 203-208 ◽  
Author(s):  
J. Enz ◽  
S. Riekehr ◽  
V. Ventzke ◽  
N. Sotirov ◽  
N. Kashaev

Author(s):  
D.J. Sordelet ◽  
P. Huang ◽  
M.F. Besser ◽  
E. Lepecheva

Abstract A brief feasibility study was performed to produce thermal spray coatings using gas atomized powders of Cu47Ti34-xZr11Ni8Six, where x=0 and 1. These alloys have previously been shown to be capable of forming metallic glasses having thick (1-2 cm) cross sections because they can be cooled from the melt at relatively low cooling rates (e.g., 100-102Ks-1). The properties of these metallic glasses include high strength, high elasticity and high fracture toughness. Amorphous plasma arc sprayed coatings were produced which were close in composition to the starting powders, and exhibited comparable glass transition and crystallization behavior. The amorphous structure of the as-sprayed coatings was used as a source for forming a range of partially devitrified and fully crystallized structures. The average hardness of the coatings increased from around 6 GPa to near 10 GPa as the degree of crystallization increased.


Metals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 792 ◽  
Author(s):  
Panos Efthymiadis ◽  
Khalid Nor

Laser welding of dissimilar high-strength steels was performed in this study for two different geometries, flat and circular samples with material thicknesses of 5 and 8 mm. The material combinations were a low carbon to a medium or high carbon steel. Three different welding systems were employed: a Nd:YAG, a CO2 and a fiber laser. The process stability was evaluated for all the experiments. The resulting full penetration welds were inspected for their surface quality at the top and bottom of the specimens. Cross sections were taken to investigate the resulting microstructures and the metallurgical defects of the welds, such as cracks and pores. Significant hardening occurred in the weld region and the highest hardness values occurred in the Heat Affected Zone (HAZ) of the high carbon steel. The occurrence of weld defects depends strongly on the component geometry. The resulting microstructures within the weld were also predicted using neural network-simulated Continuous Cooling Transformation (CCT) diagrams and predicted the occurrence of a mixture of microstructures, such as bainite, martensite and pearlite, depending on the material chemistry. The thermal fields were measured with thermocouples and revealed the strong influence of component geometry on the cooling rate which in term defines the microstructures forming in the weld and the occurring hardness.


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