scholarly journals Electroplastic effect in metals

2018 ◽  
pp. 65-76 ◽  
Author(s):  
О. A. Тroitsky
Keyword(s):  
Metal Resistance ◽  
Thin Sheets ◽  
Electric Resistance ◽  
Electroplastic Effect ◽  
Axial Texture ◽  
Resistance To Deformation ◽  
Energy Consuming ◽  
Metal Processing ◽  
Deformation By Rolling ◽  
Texture Perfection

A mechanism of electroplastic effect considered as well as possible areas of its technological application during rolling, drawing, stamping of thin sheets and other methods of metals forming.A conception justified that metal electroplastic deformation, based on electroplastic effect, can be applied at middle and final metallurgical stage. Electroplastic effect allows to decrease metal resistance to deformation by 25–30% and increase the ductility of a metal during its forming, to increase residual ductility till 30%. Due to increasing of axial texture perfection degree of wire during drawing technology with electroplastic effect application, a decrease of its electric resistance by 15% is reached. During the metal electroplastic deformation of stainless steels the austenite-martensitic phase γ→α transformation is practically completely suppressed, which makes unnecessary operations of money-and energy consuming austenizating annealing.Based on electroplastic effect about 45 mills and powerful metal-processing facilities, using metal electroplastic effect deformation created in different countries (mainly in Russia, South Korea, Italy, Great Britain and China). Different variants of effective energy-saving critical technologies are being developed by metal electroplastic effect deformation by rolling, drawing, stamping and flatting, as well as briquetting of metal wastes with current. A new equipment is created and existing equipment is modernized for application of metal еlectroplastic effect deformation technology.

Metal resistance to deformation of drill pipes steels

2020 ◽  
Vol 76 (8) ◽  
pp. 826-829
Author(s):  
A. V. Zinchenko ◽  
B. V. Barichko ◽  
V. D. Nikolenko ◽  
T. N. Zharkaya ◽  
V. L. Neroznikov
Keyword(s):  
Sample Volume ◽  
Metal Resistance ◽  
Temperature Deformation ◽  
Technological Parameters ◽  
Isothermal Exposure ◽  
Sample Height ◽  
Resistance To Deformation ◽  
Current Variation ◽  
Deformation Force ◽  
Drill Pipes

To define the energy and force parameters of metal forming processes, it is needful to know the value of the strain resistance. Evaluation of influence of hot deformation technological parameters of steels on the value of metal resistance to plastic deformation was done. For the study samples of 25ХГФМА and 32Г2У steels were used in the form of cylinders of 8.0 mm diameter and 12.0 mm height. The hot upsetting of the samples was accomplished at the Gleeble-3800 simulator of thermo-mechanical processes. Heating of the samples, placed in a vacuum chamber, was done directly by passing electric current through them. The samples were heated to deformation temperature with rate of 5 °C/sec, followed by an isothermal exposure within 3 min to make the temperature even in the sample volume. The deformation was accomplished at the temperatures 1000, 1050, 1100, 1150, 1200, 1250°C and deformation rate 1.0 and 0.1 sec–1. To prevent welding of the samples to the surface of the working instrument (hardmetal striker), a 0.1 mm thick molybdenum foil was placed between a sample and strikers. In the process of the experiment, the sample temperature, deformation force and current variation of a sample height were recorded. It was determined, that parameters of resistance to deformation, obtained in the process of the experiment by using Gleeble-3800, were higher by 25–30%, than those cited in literature, which were obtained by using a multi-cam plastometer. The specified data on the resistance to deformation were intended for application at PJSC “Tagmet” when designing technological modes of ends upsetting of drill pipes made of steels 32Г2У and 25ХГМФА to define the upsetting force.

Ecological impact of 100 years of metal processing at Prescot, northwest England

1996 ◽  
Vol 4 (1) ◽  
pp. 8-24 ◽  
Author(s):  
Nicholas M. Dickinson ◽  
Shaun A. Watmough ◽  
Andrew P. Turner
Keyword(s):  
Rural Areas ◽  
Metal Tolerance ◽  
Ecological Impact ◽  
Metal Resistance ◽  
Tree Seedlings ◽  
Copper Refinery ◽  
Particulate Copper ◽  
Metal Processing ◽  
Metal Processing Industry ◽  
Food Chain Transfer

The environmental legacy of 100 years of a metal processing industry is evaluated, based on a case study of ecotoxicological research that has been carried out in the area surrounding a copper refinery, a cadmium alloying plant, and a brass foundry at Prescot, northwest England. Aerial fallout of particulate copper and cadmium has been very localized, but soluble and potentially more toxic forms of the metals have been transported further. Accumulation of Cu and Cd in soils to exceptionally high levels has occurred, with Zn and Pb also highly elevated, but depth profiles, spatial dispersion patterns, mobility, and speciation vary between metals. A very limited effect on tree growth is apparent, although phytotoxic symptoms are readily observed in tree seedlings. Site contamination is reflected in metal concentrations in tree rings. Significant food chain transfer of Cu and Cd to invertebrates and small mammals has occurred, affecting population sizes of invertebrates and producing toxicological symptoms in shrews. Copper may have been a cause of concern for livestock in surrounding rural areas and human ingestion of metals may have been significant in the past, but currently both are likely to be negligible. Impingent metals have led to selection for metal resistance in some plant species; metal tolerance traits in grasses appeared rapidly in lawns in the area and the intensity of tolerance in plants directly reflects the localized degree of contamination. Cellular metal tolerance traits have been induced in trees as an acclimation response to metal contamination. Declining industrial activity in recent years has resulted in unexpected pulses of plant-available soil Cd and of several other metals including Mn, Ca, Mg, and Ni. Metal disappearance rates from surface horizons are also higher than expected following recent cessation of metal processing, and the fate of these transitory metals presents further cause for concern.Key words: heavy metals, ecosystem, food chains, pollution, metal tolerance.

ASSESSMENT OF HEAVY METALS TOLERANCE OF BACTERIAL ISOLATES FROM EFFLUENT OF METAL PROCESSING INDUSTRIES

2021 ◽  
pp. 60-63
Author(s):  
Attar Sayara Bashir ◽  
Rajendra D. Joshi
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Heavy Metal Resistance ◽  
Metal Resistance ◽  
Microbiological Analysis ◽  
Bacterial Isolates ◽  
Copper Nickel ◽  
Metal Processing ◽  
Metals Tolerance ◽  
Cadmium Zinc

In this study heavy metals tolerance of bacterial isolates from efuent of metal processing industries was carried out. The microbiological analysis total of 6 industrial efuents samples were collected from various industries, and total of 42 isolates were obtained among these isolates were screed for heavy metals tolerance/resistance, among them one isolate SR6a (Achromobactor) was resistant to Cu at higher concentration (2000ppm) and considered as potential heavy metal resistance isolate. The some isolates such SR3f (Bacillus), SR4g (Achromobactor), SR5c (Bacillus), and SR3a (Pseudomonas) were multi heavy metal resistance ones. All these isolates from metal industrial efuents showed the heavy metal resistance against Copper, Nickel, Cadmium, Zinc and Mercury. the isolate SR6a identied as Achromobactor sp. was able to tolerate the heavy metal up to 3000 ppm concentration and can be very useful for the application in the environmental bioremediation.

Comparison of Acrylamide and Agar Gels by Freeze-Etching

1977 ◽  
Vol 35 ◽  
pp. 606-607
Author(s):  
Russell L. Steere ◽  
Eric F. Erbe
Keyword(s):  
Electron Microscope ◽  
Sodium Hydroxide ◽  
Sodium Hypochlorite ◽  
Chromic Acid ◽  
Distilled Water ◽  
Thin Sheets ◽  
Acid Cleaning ◽  
Agar Gels ◽  
Freeze Etching ◽  
Water Cut

Thin sheets of acrylamide and agar gels of different concentrations were prepared and washed in distilled water, cut into pieces of appropriate size to fit into complementary freeze-etch specimen holders (1) and rapidly frozen. Freeze-etching was accomplished in a modified Denton DFE-2 freeze-etch unit on a DV-503 vacuum evaporator.* All samples were etched for 10 min. at -98°C then re-cooled to -150°C for deposition of Pt-C shadow- and C replica-films. Acrylamide gels were dissolved in Chlorox (5.251 sodium hypochlorite) containing 101 sodium hydroxide, whereas agar gels dissolved rapidly in the commonly used chromic acid cleaning solutions. Replicas were picked up on grids with thin Foimvar support films and stereo electron micrographs were obtained with a JEM-100 B electron microscope equipped with a 60° goniometer stage.Characteristic differences between gels of different concentrations (Figs. 1 and 2) were sufficiently pronounced to convince us that the structures observed are real and not the result of freezing artifacts.

SYSTEMIC CAUSES OF THE APPEARANCE OF “COBRA EFFECT” IN THE MANAGEMENT OF SOCIO-ECONOMIC DEVELOPMENT

2019 ◽  
Vol 86 (3) ◽  
pp. 51-61
Author(s):  
M. S. Mokiy ◽  
E. K. Borzenko
Keyword(s):  
Economic Development ◽  
Economic System ◽  
Gross National Product ◽  
The Family ◽  
Social And Economic Development ◽  
Socio Economic Development ◽  
Energy Consuming ◽  
The Right ◽  
Goals And Objectives ◽  
Least Energy

The article on the basis of extrapolation of system laws of management of social and economic development illustrates the system reason of the Cobra effect, that is, a situation where, despite the rather attractive goals that managers formulate, the result of the activities of subordinates is opposite to what was intended. The main problem of management is the development of a system of indicators, in which, working on the indicator, employees would change the state in the right direction. The reason for the Cobra effect is the manifestation of systemic patterns of socio-economic development. The main system regularity is the desire of the system for stability and self-preservation. This state of the system is achieved using the least energy-consuming way. It is shown that any worker, realizing system regularities, aspires to stability and self-preservation. Therefore, the employee is always forced to work for achieving the indicator. The article analyzes the manifestation of these laws at the level of enterprises and state. When managers understand these patterns explicitly or covertly, changes in the economic system are moving in the right direction. It is shown that the existing system of target indicators used as indicators to assess the effectiveness of management does not meet the goals and objectives of socio-economic development. At the meso- and macrolevel, absolute, volumetric indicators, such as gross national product and others, reduce the range of benefits to the population. The article defines the vector of change in the system of indicators for assessing the effectiveness of management at the regional and state levels, based on the fact that the key element is the family. At the same time, the targets should be indicators to assess the availability of benefits for households.

Influence of Weld Oxides on Ductility and Fracture Toughness of Electric Resistance Welded Joint

1994 ◽  
Vol 80 (4) ◽  
pp. 324-329
Author(s):  
Tetsuya TAGAWA ◽  
Syuuhei YAMAMOTO ◽  
Takashi MIYATA
Keyword(s):  
Fracture Toughness ◽  
Welded Joint ◽  
Electric Resistance
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