scholarly journals Increasing the mechanical properties of structural cast iron for machine-building parts by combined Mn – Al alloying

2022 ◽  
pp. 118-130
Author(s):  
Stanislav Popov ◽  
Liliia Frolova ◽  
Oleksii Rebrov ◽  
Yevheniia Naumenko ◽  
Оlenа Postupna ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Cast Iron ◽  
Carbon Content ◽  
Ultimate Strength ◽  
Machine Building ◽  
Factor Space ◽  
Al Content ◽  
All Solutions ◽  
Mn Content ◽  
Input Variables

The object of research in this work was cast iron for machine-building parts, alloyed with Al. The possibility of improving the mechanical properties of cast iron by choosing the optimal Mn – Al combinations, depending on the carbon content in the cast iron, was determined. The study was carried out on the basis of available retrospective data of serial industrial melts by constructing the regression equation for the ultimate strength of cast iron in the three-factor space of the input variables C – Mn – Al. The optimization problem was solved by the ridge analysis method after reducing the dimension of the factor space by fixing the carbon content at three levels: C = 3 %, C = 3.3 %, and C = 3.6 %. It was found that the maximum values of the ultimate strength are achieved at the minimum level of carbon content (C = 3%) and are in the range of values close to 300 MPa. In this case, the Al content is in the range (2.4–2.6) %, and the Mn content is about 0.82 %. With an increase in the carbon content, there is a tendency to a decrease in the content of Mn and Al in the alloy, which is necessary to ensure the ultimate strength close to 300 MPa. The results of the ridge analysis of the response surface also showed that at the upper limit of the carbon content (C = 3.6%), it is not possible to reach the ultimate strength of 300 MPa in the existing range of Mn and Al variation. All solutions are verified for the following ranges of input variables C = (2.94–3.66) %, Mn = (0.5–1.1) %, Al = (1.7–2.9) %. Graphical-analytical descriptions of the optimal Mn – Al ratios are obtained, depending on the actual content of carbon in the alloy, which make it possible to purposefully select the optimal melting modes by controlling the tensile strength of the alloy

scholarly journals ВПЛИВ УМОВ ІЗОТЕРМІЧНОГО ГАРТУВАННЯ НА ПСЕВДОПРУЖНУ ПОВЕДІНКУ БЕЙНІТНОГО ЧАВУНУ

World Science ◽  
2019 ◽  
Vol 1 (1(41)) ◽  
pp. 15-23
Author(s):  
Подрезов Ю. М. ◽  
Романко П. М. ◽  
Холявко В. В. ◽  
Марченко Н. М.
Keyword(s):  
Mechanical Properties ◽  
Cast Iron ◽  
Cost Effective ◽  
Ductile Cast Iron ◽  
Machine Building ◽  
Isothermal Quenching ◽  
Clear Understanding ◽  
Tempering Temperature ◽  
Theoretical Concepts ◽  
Damping Behavior

Application of ductile cast iron ADI is feasible and cost-effective, provided that there is a clear understanding of the mechanisms for the formation of their high complex mechanical properties. The use of such materials for the production of variable parts of machinery, or in other units of automobile and machine building will significantly extend the life of the equipment. It is established that the level of mechanical characteristics of the ADI cast iron varies in full accordance with the theoretical concepts of the influence of the tempering temperature on the formation of mechanical properties of such materials. The previous plastic deformation does not affect the mechanism of formation of pseudo-elasticity. The tendency to dampening increases with an increase in the temperature of isothermal quenching. The damping behavior of a material is a consequence of the formation of pseudo-elastic twins in the structure of the transformed martensite.

scholarly journals Mathematical model of the mechanical properties of Ti-alloyed hypoeutectic cast iron for mixer blades

2021 ◽  
pp. 99-110
Author(s):  
Sergei Kharchenko ◽  
Andriy Barsuk ◽  
Nurlana Karimova ◽  
Alexander Nanka ◽  
Yevhen Pelypenko ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Mathematical Model ◽  
Wear Resistance ◽  
Cast Iron ◽  
Chemical Composition ◽  
Ultimate Strength ◽  
Abrasion Resistance ◽  
Resistance Coefficient ◽  
Regression Equations ◽  
Selection Of

The object of research is hypoeutectic cast iron intended for cast parts operating under abrasive friction conditions. Such parts are mixer blades, the operational properties of which include durability, assessed by abrasion resistance and strength. To give the blades such properties, cast irons, which are materials of the blades, are alloyed with elements that contribute to the formation of carbides of various compositions. The main problem that impedes the targeted selection of materials for mixer blades or finished blades from different materials or different chemical composition is the lack of substantiated selection criteria. If the shipment is carried out only with the provision of data on the chemical composition of the alloy, it is necessary to be able to evaluate the expected mechanical properties, in particular abrasion resistance and strength. Using the methods of regression analysis, a mathematical model has been obtained that includes two regression equations, which allows for a targeted selection of the chemical composition that provides the maximum possible value of mechanical properties – ultimate strength and coefficient of wear resistance. Optimization of the chemical composition, carried out according to this model, made it possible to determine the following chemical composition: C=2.94 %, Ceq=3.3 %, Ti=1.56 %, providing the maximum ultimate strength σb=391 MPa; C=2.78 %, Ceq=3.14 %, Ti=1.61 %, providing a maximum wear resistance coefficient Kwr=12 %. In the case of priority of the strength criterion, the calculated optimal chemical composition makes it possible to reduce the mass-dimensional characteristics of the mixing units of the mixers. A procedure is proposed for using this model to select a batch of blades with the expected best performance properties

Effect of Carbon Content on Microstructure and Properties of Gray Cast Iron

2014 ◽  
Vol 971-973 ◽  
pp. 44-48
Author(s):  
Ya Li Sun
Keyword(s):  
Mechanical Properties ◽  
Cast Iron ◽  
Carbon Content ◽  
Liquid Iron ◽  
Gray Cast Iron ◽  
Gray Cast ◽  
Carbon Equivalent ◽  
Microstructure And Properties ◽  
Metallographic Observation ◽  
Equivalent Control

Though the study of carbon content on the microstructure and properties of gray cast iron, mechanical properties test as well as metallographic observation, we could see that the mobility of molten iron is the best when carbon equivalent control at around 4.3%; Liquid iron tend to precipitate A or B type graphite and enhance the casting organization and property when carbon content was increased properly.

Teknologi Inokulasi Besi Cor Kelabu FC-250 Untuk Mencegah Pengerasan Pada Dove Tale Produk Ragum Tipe 125

2019 ◽  
Vol 16 (2) ◽  
Author(s):  
Amin Suhadi ◽  
Seodihono
Keyword(s):  
Mechanical Properties ◽  
Cast Iron ◽  
Treatment Process ◽  
Gray Cast Iron ◽  
Spare Parts ◽  
Gray Cast ◽  
Micro Structure ◽  
Control Factors ◽  
Seed Inoculation ◽  
Casting Industry

Production technology of metal casting industry in Indonesia needs to be improved, especially in the manufacturing of spare parts and box engine made of gray cast iron which has various wall thick such as dove tale construction. Microstructure of gray cast iron is influenced by cooling rate during casting, chemical composition and melting treatment process (inoculation). The part which has the thinnest thickness has the fastest cooling therefore, the grain boundary is smaller compared to other section. As a result this part has highest hardness and difficult to be machined. This research is conducted to solve this problem by modifying melting and solidification treatment process. The research starting from micro structure analysis, composition and mechanical properties tests on the product, and then conducting modification treatment through Taguchi method approach. Experimental results obtained show that the best level settings to control factors which affect to the uniformity of the microstructure and mechanical properties in gray cast iron is the addition of seed inoculation super ® 75, as much as 0.25% with the method of inoculation material entering into the Transfer Ladle.Teknologi produksi pada industri pengecoran di Indonesia masih membutuhkan perbaikan terutama dalam pembuatan komponen mesin perkakas dan peralatan pabrik yang terbuat dari besi tuang kelabu yang mempunyai variasi ketebalan yang besar seperti konstruksi ekor burung (dove tale). Pada pengecoran, struktur mikro dari besi tuang kelabu sangat dipengaruhi oleh kecepatan pendinginan, komposisi kimia dan proses perlakuan pada logam cair (inokulasi). Bagian yang mempunyai ukuran paling tipis mempunyai kecepatan pendinigan paling tinggi karena itu ukuran butirnya jauh lebih kecil dari bagian lain, akibatnya bagian ini mempunyai kekerasan lebih tinggi dan sulit dilakukan pengerjaan mesin. Penelitian ini bertujuan untuk memperbaiki hal ini yang terjadi pada dove taledengan cara memodifikasi proses perlakuan pada cairan besi dan proses pendinginan. Penelitian dimulai dari analisa struktur mikro, pengujian komposisi kimia, pengujian sifat mekanis pada produk kemudian dilakukan modifikasi menggunakan pendekatan metode statistik Taguchi. Hasil penelitian menunjukkan bahwa pengaturan terbaik yang dapat diperoleh untuk mendapatkan keseragaman struktur mikro dan sifat mekanis pada pengecoran besi tuang kelabu adalah penambahan seed inoculation super ® 75, sebesar 0.25% dengan metode pemasukan inokulasi kedalam Ladle pengangkut logam cair.Keywords: carbon, micro structure, hardness, inoculation

Determination of mechanical properties of two-phase and hybrid nanocomposites: experimental determination and multiscale modeling

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mahmoud Haghighi ◽  
Hossein Golestanian ◽  
Farshid Aghadavoudi
Keyword(s):  
Mechanical Properties ◽  
Ultimate Strength ◽  
Multiscale Modeling ◽  
Filler Content ◽  
Hybrid Nanocomposites ◽  
Dynamics Simulation ◽  
Strength Increase ◽  
Two Phase ◽  
Macro Scale ◽  
Elongation To Failure

Abstract In this paper, the effects of filler content and the use of hybrid nanofillers on agglomeration and nanocomposite mechanical properties such as elastic moduli, ultimate strength and elongation to failure are investigated experimentally. In addition, thermoset epoxy-based two-phase and hybrid nanocomposites are simulated using multiscale modeling techniques. First, molecular dynamics simulation is carried out at nanoscale considering the interphase. Next, finite element method and micromechanical modeling are used for micro and macro scale modeling of nanocomposites. Nanocomposite samples containing carbon nanotubes, graphene nanoplatelets, and hybrid nanofillers with different filler contents are prepared and are tested. Also, field emission scanning electron microscopy is used to take micrographs from samples’ fracture surfaces. The results indicate that in two-phase nanocomposites, elastic modulus and ultimate strength increase while nanocomposite elongation to failure decreases with reinforcement weight fraction. In addition, nanofiller agglomeration occurred at high nanofiller contents especially higher than 0.75 wt% in the two-phase nanocomposites. Nanofiller agglomeration was observed to be much lower in the hybrid nanocomposite samples. Therefore, using hybrid nanofillers delays/prevents agglomeration and improves mechanical properties of nanocomposite at the same total filler content.

Sign in / Sign up

Export Citation Format

Share Document