NEW STEELS AND TECHNOLOGIES FOR NITRIDED PARTS OF LONG LIFE MACHINES

The analysis of the used steels for nitrided parts is carried out. On the basis of a new methodology for increasing the strength of structural steels and parts, new scientific approaches and practical solutions are proposed and considered for the creation of gear wheels strengthened by nitriding both when using aluminum containing steels and a new material, 40ХМФА (40KhMFA) steel, that does not contain aluminum. To improve the efficiency and manufacturability of parts production from aluminum-containing 38Х2МЮА (38Kh2MYuA) steel, widely used in mechanical engineering, a fundamentally new technology of preliminary heat treatment of part blanks, “incomplete quenching”, has been developed, which provides both an increase in the machinability and accuracy of large-sized gear wheels, and an increase in strength due to the elimination of flaking of nitrided layer. The research results are presented on 40ХМФА (40KhMFA) steel, which does not contain aluminum, has increased heat resistance, hardenability and workability of parts, as well as the characteristics of the hardened layer. The nitrided layer of gears with a thickness of 0.5–0.7 mm does not contain brittle components, which, with a core hardness of 300–320 HB, also excludes its flaking and subsequent destruction of parts. The use of 40ХМФА (40KhMFA) steel makes it possible to solve the problems of reliability and life of large-sized nitrided gears, but it is also promising for the entire range of gears with internal gearing, as well as parts of movable spline gearings and fine-modular gears in order to replace carburizing with nitriding.

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Experience and prospects of use of structural steels for nitridated gears

Proceedings of the National Academy of Sciences of Belarus Physical-Technical Series ◽

10.29235/1561-8358-2021-66-1-58-65 ◽

2021 ◽

Vol 66 (1) ◽

pp. 58-65

Author(s):

P. A. Vityaz ◽

V. I. Moiseenko ◽

A. G. Sidorenko ◽

M. V. Sotnikov ◽

N. D. Shkatulo ◽

...

Keyword(s):

Nitrided Layer ◽

New Technology ◽

High Hardness ◽

Hardened Layer ◽

High Wear Resistance ◽

Preliminary Heat Treatment ◽

New Material ◽

Core Hardness ◽

Nitrided Surface ◽

Gear Wheels

The experience of using known and new steels to improve the manufacturability and strength of the main parts of machines, hardened by nitriding, is generalized. New approaches to manufacture of gear wheels hardened by nitriding, both when using aluminum-containing steels and a new material, steel 40ХМФА, are considered. To improve the efficiency and man ufacturability of parts production from aluminum-containing steel 38Х2МЮА, widely used in mechanical engineering, a fundamentally new technology of preliminary heat treatment of workpieces of parts – “incomplete hardening” has been developed, which provides both an increase in the machinability and accuracy of large-sized gear wheels, and an increase in strength due to the elimination of the brittleness of nitrided layer. The high hardness of the nitrided surface of the parts – up to 900 HV – also ensures high wear resistance of the parts. Gear wheels made of new aluminum-containing steel 20ХН4МФЮА solidified at the nitriding stage, have strength characteristics equal to cemented parts, which allows not only increasing the bearing capacity of a number of products, but significant simplification of the technology of manufacturing precise parts that are complex in shape, replacing carburizing with nitriding, thereby eliminating the necessary after-carburizing finishing operation – grinding. Steel 40ХМФА, which does not contain aluminum, has increased heat resistance, hardenability and machinability of parts, as well as the characteristics of their hardened layer. The nitrided layer of gears 0.5–0.7 mm thick does not contain brittle components, which, with a core hardness of 300–320 HB, excludes its “flaking” and subsequent destruction of parts. The use of 40ХМФА steel makes it possible to solve the problems of reliability and service life of large-sized nitrided gears, but it is also promising for the entire range of gears with internal gearing, as well as parts of movable spline gearings. These characteristics also in some cases allow replacing the carburizing of gears (modulus less than 4 mm) by nitriding when using 40ХМФА steel.

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Analytical Methods for the Synthesis of Composites

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.847.167 ◽

2020 ◽

Vol 847 ◽

pp. 167-172

Author(s):

Irina Garkina ◽

Alexander Danilov

Keyword(s):

New Technology ◽

Hierarchical Structures ◽

Structural Description ◽

Adequate Model ◽

Structure Quality ◽

Criterion Space ◽

New Material ◽

Evolution Of Ideas ◽

Technology Identification

The evolution of ideas about materials is analyzed: the initial accumulation of data, experience and skills in the production of new material (the emergence of new technology); identification of patterns of influence of various factors on the properties of the material with the involvement of fundamental sciences (the formation of a new technology); obtaining building material with a given level of quality (development of an effective technology ); identification of the technological process and the construction of an adequate model of “recipe-technological factors - structure - quality of the material”. In models of structural material science, the existence of certain hierarchical structures of objects considered as systems is assumed; model selection is determined by the objectives of the structural description of the object at each scale level. The shift of paradigms based on the basic models of a continuous self-developing environment to the side of paradigms based on models of a structured self-developing environment based on the ideas and methods of a systematic approach and synergetics is indicated. The approaches to the fundamentalization of the synthesis of materials based on their own experience in designing materials for special purposes are presented: the presentation of the material in the form of a complex system (at first - poorly structured with conflicting goals and criteria); quality assessment of composite materials; formalization of kinetic processes; material quality management; minimization of dimension of criterion space; multi-criteria optimization.

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Analysis of New Materials of Computer Memory

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.416-417.1657 ◽

2013 ◽

Vol 416-417 ◽

pp. 1657-1660 ◽

Cited By ~ 1

Author(s):

Qiu Ju Zheng

Keyword(s):

New Technology ◽

Ferroelectric Materials ◽

External Memory ◽

Computer Memory ◽

Hard Disks ◽

Storage Materials ◽

Modern Computer ◽

New Material ◽

New Research ◽

Oxide Crystals

Modern computer memory, in addition to cache memory, is mainly divided into two categories: internal memory and external memory. External memory mainly comprises of magnetic or optical disks, floppy disks, tapes, like hard disks, CDs, which can store information, and do not depend on electricity to save information. In the new technology, the computer memory materials are facing a revolution of industry upgrade. In this paper, based on a lot of information the author makes a brief analysis of the new material of the external memory, that is, the phase change storage materials, titanium oxide crystals form materials, magnetic materials and organic ferroelectric materials, and comprehensively promote the new research and new development of computer storage materials.

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Influence of hardened layer structure and coating-substrate interface geometry on plastic deformation pattern of structural steels at mesolevel

Proceedings KORUS 2000. The 4th Korea-Russia International Symposium On Science and Technology ◽

10.1109/korus.2000.866117 ◽

2002 ◽

Cited By ~ 1

Author(s):

A. Koval ◽

S. Panin

Keyword(s):

Plastic Deformation ◽

Layer Structure ◽

Hardened Layer ◽

Structural Steels ◽

Deformation Pattern ◽

Substrate Interface ◽

Interface Geometry

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New Technology on Seismic Reinforcement of Pile Foundation for Long Life Bridges

Procedia Engineering ◽

10.1016/j.proeng.2017.01.443 ◽

2017 ◽

Vol 171 ◽

pp. 1035-1042 ◽

Cited By ~ 1

Author(s):

Koichi Tomisawa ◽

Makoto Kimura

Keyword(s):

Pile Foundation ◽

New Technology ◽

Long Life

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INVESTIGATION METHOD OF THERMAL FRICTION PROCESSING OF THE ECCENTRIC CONE CRUSHER PART

NEWS of National Academy of Sciences of the Republic of Kazakhstan ◽

10.32014/2020.2518-170x.153 ◽

2020 ◽

Vol 6 (444) ◽

pp. 245-253

Author(s):

K. T. Sherov ◽

◽

T. M. Buzauova ◽

B. T. Mardonov ◽

A. Zhauyt ◽

...

Keyword(s):

New Technology ◽

Hardened Layer ◽

Middle Part ◽

Cone Crusher ◽

Layer Increase ◽

Increase Productivity ◽

Mechanical Cutting ◽

High Level ◽

Bearing Rings ◽

Study Performance

The article presents the results of the study performance of cone crushers and the existing technology restoration of their parts. The main reasons for the failure of cone crushers are the following: failure armor of the cone and the middle part, the protective cap, parts of the upper suspension, dust seal rings, bearing rings, the eccentric of the crusher. The most time-consuming is to restore the details of the eccentric crusher. A new technology restoration worn surfaces of the eccentric part and the results of an experimental study of thermal friction treatment (TFТ) after surfacing are proposed. It is revealed that despite the high level of temperature corresponding to intensive treatment modes it is possible to achieve effective hardening. Implementation of the proposed technology allows: eliminate the undesirable effects of softening due to re-riveting and reduce the oxidized layer; increase productivity relative to mechanical cutting methods in 23 times and tool life of more than 10 times; the use of affordable cheap material steel 45, 50, 60G for the manufacture of tools and perform processing at more intensive modes S =0,2-1mm / Rev; n=2000-3000 rpm. It is established that the TFO of the deposited surface part eccentric, provides wear resistance of the treated surfaces parts in 2….8 times more than the factory processing technology, while the depth of the hardened layer can be 1.5…. 2 mm.

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The application of a new, innovative, hybrid technology combining hardfacing and nitriding to increase the durability of forging tools

Archives of Civil and Mechanical Engineering ◽

10.1007/s43452-020-00122-1 ◽

2020 ◽

Vol 20 (4) ◽

Author(s):

Marcin Kaszuba

Keyword(s):

Wear Resistance ◽

Surface Layer ◽

Layer Structure ◽

Nitrided Layer ◽

New Technology ◽

Hot Forging ◽

Hybrid Technology ◽

Multiple Treatment ◽

Operational Tests ◽

The Impact

Abstract The article deals with the wear of forging tools used in hot forging processes. The research presented in the work includes analysis of tool life used in a selected industrial hot die forging process. Multiple treatment variants were used to increase wear resistance, including thermo-chemical treatment (nitriding), welding methods (surfacing) and an innovative new hybrid technology combining surfacing and nitriding. First of all, the research focused on determining the impact of the phase structure of the nitrided layers used and the surfacing layer on resistance to destructive factors occurring in the analyzed process. Next, hybrid treated tools combining surfacing and nitriding were also subjected to operational tests. Each of the tools analyzed in this work was operated until it was withdrawn due to excessive wear, and then subjected to comprehensive analysis. The tests of tools after operation included: surface scanning to determine the amount of wear of the analyzed tools after work, microhardness measurement, and microscopic tests. A detailed analysis of changes in the surface layer of tools in selected areas was made using a scanning microscope. The aim of the study was to assess the effectiveness of the hybrid surface treatment process used to increase the wear resistance of the surface layer of tools and thereby improve the durability of the forged tools analyzed. The obtained research results indicate a beneficial effect of using the new technology resulting in 300% increase in the durability of the analyzed tools. The effect of improving durability confirmed by obtained results arises from the use of hybrid layers, which are more resistant to abrasive wear and to cracking due to thermo-mechanical fatigue. Moreover, the study shows that nitriding may have a beneficial influence on improving the lifetime of forging tools, under the condition that the nitrided layer has an α diffusive layer structure, without a larger amount of γ’ and ε nitride precipitates.

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