Izvestiya Vysshikh Uchebnykh Zavedenij. Chernaya Metallurgiya最新文献

{"title":"Sintered powder high-entropy target cathodes for wear-resistant coatings","authors":"S. N. Grigor’ev, M. Sh. Migranov, M. A. Volosova, A. S. Gusev","doi":"10.17073/0368-0797-2023-4-410-414","DOIUrl":"https://doi.org/10.17073/0368-0797-2023-4-410-414","url":null,"abstract":"Modern machine-building production equipped with high-performance mechatronic systems and numerically-controlled and adaptive control machines for blade cutting of heat-resistant chromium-nickel and titanium alloys requires increasing the operating properties of cutting tools working at high temperature-force loads in the contact zone, respectively with a significant stress-strain state of the cutting wedge. It is possible to solve the problem of increasing wear resistance and serviceability by developing and introducing new tooling material, as well as by applying wear-resistant coatings. The paper presents the results on development of technology for obtaining high-entropy target cathodes by spark plasma sintering with subsequent application of wear-resistant coatings on metal-cutting tools by both magnetron and ion-plasma methods. Samples of sintered high-entropy target cathodes of different compositions (more than fourteen) and at different modes of their sintering (depending on temperature in five modes) with their subsequent optimization and two standard sizes (20 and 80 mm) were obtained for further application of wear-resistant coatings on the magnetron unit. The authors carried out structural and phase analysis and studied physicomechanical properties of the obtained high-entropy target cathodes: density, hardness, electrical conductivity, emissivity. The possibility of obtaining high-entropy target cathodes by spark plasma sintering was confirmed experimentally, and the effect of sintering temperature on structure and properties of the sintered samples of high-entropy target cathodes was established. Dependence of physicomechanical and electrophysical parameters of target cathodes on technological modes of spark plasma sintering is shown.","PeriodicalId":35527,"journal":{"name":"Izvestiya Vysshikh Uchebnykh Zavedenij. Chernaya Metallurgiya","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135022112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of ring groove in a heat-insulating insert on efficiency of its work in blast channel of blast furnace tuyere","authors":"S. V. Albul, O. A. Kobelev, I. A. Levitskii","doi":"10.17073/0368-0797-2023-4-415-420","DOIUrl":"https://doi.org/10.17073/0368-0797-2023-4-415-420","url":null,"abstract":"One of the main disadvantages when supplying natural gas to the air tuyere of a blast furnace is low intensity of its combustion inside the tuyere blast channel. Ring groove on the surface of blast channel improves the mixing of natural gas with blast and increases completeness of gas combustion in it, but reduces the tuyere durability. One of the ways to simultaneously solve these problems is to install a heat-insulating ceramic insert in the tuyere blast channel. The insert significantly reduces heat losses through the tuyere surface, improves natural gas combustion in the blast channel due to its contact with hot walls of the insert instead of cold copper walls in its absence. This increases the temperature of the hot blast at the tuyere outlet. In addition, the insert affects the tuyere durability by reducing the heat flow acting on the tuyere. In this work, we studied influence of the ring groove and its parts in the insert on efficiency of its work. In the Ansys 21.1 software, the processes occurring in the blast channel of a blast furnace tuyere with a ceramic insert installed in it, having a groove of a quadrangular section in the form of a ring or its part in the circumferential direction, were simulated. It was established that improvement of natural gas combustion in the tuyere blast channel is achieved using a ring groove or part of it from the side of gas supply.","PeriodicalId":35527,"journal":{"name":"Izvestiya Vysshikh Uchebnykh Zavedenij. Chernaya Metallurgiya","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135022110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of flux-cored wire of Fe – C – Si – Mn – Cr – W – V system with additives of carbon-fluorine-containing material and titanium","authors":"A. A. Usol’tsev, N. A. Kozyrev, L. P. Bashchenko, R. E. Kryukov, A. V. Zhukov","doi":"10.17073/0368-0797-2023-4-403-409","DOIUrl":"https://doi.org/10.17073/0368-0797-2023-4-403-409","url":null,"abstract":"The paper considers research of quality of the electric arc coating obtained using flux-cored wire of the Fe – C – Si – Mn – Cr – W – V system with additives of carbon-fluorine-containing material and titanium. The formation of an electric arc coating was carried out using an automatic arc welding machine ASAW-1250 with a new chromium-containing flux-cored wire on plates made of St3 steel. To exclude mixing of the deposited metal with the substrate steel, multilayer surfacing was conducted. The surfacing mode was calculated and refined experimentally. The authors studied the composition and properties of the surface of the electric arc coating after surfacing. As a substitute for amorphous carbon they used a carbon-fluorine-containing material (dust of gas purification of aluminum production). Surfacing was carried out under a flux made from slag produced by silicomanganese with a high content of sulfur. A regression analysis of influence of the deposited layer’s chemical composition on its hardness and wear rate was carried out and mathematical models of the investigated performance characteristics of the electric arc coating were obtained. With an increase in the content of chromium, tungsten, carbon and silicon, hardness of the deposited metal and its resistance to abrasive wear increase. The results of the conducted research make it possible to develop measures ensuring the required level of performance characteristics of the electric arc coating and can be used to make a forecast of hardness of the deposited layer and its wear resistance when the chemical composition of the metal changes, to predict the operational resistance of rolling rolls deposited with wires of the PP-Np-35V9Kh3SF type. Mathematical models of hardness of the deposited layer and its wear resistance help to clarify the mechanism of hardening and formation of protective properties of the surface layers of rolling rolls by means of electric arc coatings deposited with flux-cored wires.","PeriodicalId":35527,"journal":{"name":"Izvestiya Vysshikh Uchebnykh Zavedenij. Chernaya Metallurgiya","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135165650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reduction of specific coke consumption in blast furnace by impact on thermal reverse zone","authors":"A. S. Kharchenko, M. I. Sibagatullina, E. O. Kharchenko, I. V. Makarova, S. K. Sibagatullina, V. A. Beginyuk","doi":"10.17073/0368-0797-2023-4-394-402","DOIUrl":"https://doi.org/10.17073/0368-0797-2023-4-394-402","url":null,"abstract":"At the blast furnace of PJSC “Magnitogorsk Metallurgical Plant” (MMK), the specific consumption of coke was reduced by impact on thermal reverse zone (TRZ) by increasing the consumption of natural gas above 120 m 3 /t of cast iron under conditions of increased reactivity and reduced hot strength of coke. In the first pair of periods, an increase in CRI from 38.4 to 39.3 % with a decrease in CSR from 36.3 to 34.6 % was accompanied by an increase in the ratio of natural gas consumption and total oxygen entering the furnace from 0.43 to 0.45 by increasing the specific gas consumption from 123.2 to 133.5 m 3 /t of cast iron. The set of actions increased the TRZ length towards the blast-furnace mouth by 1.9 % with its unchanged location along the lower part. Reducing the heat consumption in the TRZ increased the temperature difference between gas and materials there by an average of 36 °С. In the second pair of periods, the consumption of natural gas was 143.9 m 3 /t of cast iron with a decrease in the oxygen content in the blast from 27.6 to 27.0. They were accompanied by the following changes in the processes under consideration: an increase in the length of the TRZ towards the blast-furnace mouth by 2.6 % and the distance from the tuyere hearth by 3.4 %, an increase in the degree of carbon reduction from 32.0 to 33.3 %, an insignificant (on average 0.3 °С) increase in the temperature difference of gas and materials in the TRZ. In the first pair of periods, reduction in the coke specific consumption was 4.7 kg/t of cast iron with an increase in furnace productivity by 27 t/day. Conditions and course of the processes of the second pair ensured a decrease in the coke specific consumption by 1.6 kg/t of cast iron and led to a decrease in cast iron production by 41 t/day.","PeriodicalId":35527,"journal":{"name":"Izvestiya Vysshikh Uchebnykh Zavedenij. Chernaya Metallurgiya","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135165649","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ТЕРМОДИНАМИЧЕСКОЕ МОДЕЛИРОВАНИЕ ВОССТАНОВЛЕНИЯ НИКЕЛЯ И ЖЕЛЕЗА ИЗ МНОГОКОМПОНЕНТНОГО СИЛИКАТНОГО РАСПЛАВА В ПРОЦЕССЕ БАРБОТАЖА. СООБЩЕНИЕ 3. ВОССТАНОВИТЕЛЬ – КОНВЕРТИРОВАННЫЙ ГАЗ","authors":"А. С. Вусихис, Леопольд Игоревич Леонтьев, Д. З. Кудинов, Евгений Николаевич Селиванов","doi":"10.17073/0368-0797-2018-12-957-962","DOIUrl":"https://doi.org/10.17073/0368-0797-2018-12-957-962","url":null,"abstract":"Common  method  of  oxidized  nickel  ores  processing  includes  ore feeding in countercurrent with high-temperature waste gases, melting in bubbling zone of a two-zone furnace, supplying carbonaceous  fuel and oxygen-containing blasting to produce melt that is reduced by  solid  reducing  agent  in  plasma  zone  when  heated  with  nitrogen.  The  main disadvantages of this method are low nickel content in alloy and  presence  of  silicon,  carbon,  chromium  and  other  impurities.  To  improve quality of ferronickel, it is proposed to use converted natural gas  in  plasma  zone,  which,  when  processed  by  plasma,  is  not  only  a heat  carrier,  but  also  a  reducing  agent.  The  method  is  based  on  assumption that at melt bubbling, composition of gas in bubbles that reached  bath surface is close to equilibrium. Gas-reducing agent is obtained by  oxygen conversion of natural gas with ratio α equal to 0.25; 0.35 and  0.50  respectively  (T = 1823 K).  Based  on  calculations,  dependencies  of content of nickel and iron oxides in silicate melt, degree of their reduction, ratio of slag and metal and nickel content in the alloy on total  gas flow determined as the product of the gas amount in a single batch  and the number of calculation cycles, as well as the amount of nickel  and iron, reduced by a single portion of gas are revealed. Regardless of proportion of hydrogen and carbon monoxide in source gases, increase  in  their  consumption  monotonously  reduces  content  of  nickel  oxide  in  the  melt,  while  content  of  iron  oxide  initially  increases,  and  then  decreases.  When  melt  is  blown  with  natural  gas  conversion  products  with  α = 0.25,  reduction  process  takes  place  due  to  hydrogen,  effect  of  CO  is  insignificant.  Flow  rate  of  54 m 3 /t  of  gas  allows  to  achieve  98.5 %  degree  of  nickel  reduction,  content  of  nickel  oxide  in  melt  is  0.028 %, ratio of slag and metal is 46 units. At equal gas consumption,  with increase in proportions of CO 2 and H 2 O in the initial mixture, by  increasing α, values of metals reduction from melt deteriorate: valu es  of  C NiO and  C FeO and  ratio  of  slag  and  metal  increase,  and  degree  of  nickel  and  iron  reduction  decreases.  Comparison  of  results  with  previously  obtained  data  on  metals  reduction  from  similar  melts  by  carbon monoxide and hydrogen has shown that hydrogen has greater efficiency, somewhat worse results are demonstrated when converted gas  with α = 0.25 is applied. Nickel reduction by converted gas (α = 0.35)  to reduction rate of 88 %, which corresponds to its consumption of  60 m 3 /t,  is  more  effective  than  by  pure  CO.  However,  final  values  of  degree of reduction using converted gas reach 90 %, while for CO they  approach 100 %.","PeriodicalId":35527,"journal":{"name":"Izvestiya Vysshikh Uchebnykh Zavedenij. Chernaya Metallurgiya","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84237753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ШЛАКИ МЕТАЛЛУРГИЧЕСКОГО ПРОИЗВОДСТВА – ПЕРСПЕКТИВНЫЙ МАТЕРИАЛ ДЛЯ РЕКУЛЬТИВАЦИИ ТЕХНОГЕННЫХ ОТХОДОВ","authors":"И. П. Беланов, Н. Б. Наумова, И. С. Семина, О. А. Савенков","doi":"10.17073/0368-0797-2018-12-987-992","DOIUrl":"https://doi.org/10.17073/0368-0797-2018-12-987-992","url":null,"abstract":"The article describes results of the microplot field trial to investigate potential use of metallurgical slags for fracture of capillary rim  during reclamation of toxic waste dumping areas, such as enrichment  plants  tailings,  solid  waste  dumps,  etc.,  with  minimal  possible  introduction  of  fertile  soil  layer.  Such  approach  allows  energy-effective  utilization  of  metallurgical  wastes.  Four  slags,  produced  at  EVRAZ  West  Siberian  plant  by  different  technologies  were  used:  white  nonferrous, blast-furnace, converter and electric furnace slags. These slags  were used as an inert material, underlying thin fertile soil layer in experimental microplots, where perennial plants (legume-grass mixture)  were sawn. For each slag there was check variant (no fertilizer added),  and  variants  with  potassium  humic  agents,  and  their  combination  as  mineral fertilizers. Aboveground phytomass at the end of the grow ing  season varied from 17 to128 g/m2. Converter and blast furnace slags,  which had the least phytotoxicity, appeared to be better inert materials.  Mineral  fertilizer,  introduced  itself  and  combined  with  humic  agents,  has  increased  aboveground  phytomass  2 – 4 times  as  compared  with  check  variant.  Used  separately,  humic  agent  did  not  affect  plant  production,  whereas  used  together  with  mineral  fertilizer,  it  increased  phytomass  1.6 – 1.8 times.  Thus  combined  introduction  of  mineral  fertilizer  and  humic  agents  is  recommended  to  stimulate  germination  abilit y  and  phytomass  production.  Converter  and  blast  furnace  slags  can be used as inert materials for reclamation with minimal fertile soil  layer application, whereas white non-ferrous and electric furnace slags  are not recommended for such application due to their high phytotoxicity, negatively affecting growth and development of perennial plants,  used for reclamation.","PeriodicalId":35527,"journal":{"name":"Izvestiya Vysshikh Uchebnykh Zavedenij. Chernaya Metallurgiya","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76708371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ТЕРМОДИНАМИЧЕСКАЯ ОЦЕНКА ВЛИЯНИЯ ТЕМПЕРАТУРЫ НА ВОССТАНОВЛЕНИЕ ЭЛЕМЕНТОВ ИЗ ХРОМСОДЕРЖАЩЕГО РУДНО-ИЗВЕСТКОВОГО РАСПЛАВА","authors":"O. V. Zayakin, V. A. Salina, V. I. Zhuchkov","doi":"10.17073/0368-0797-2018-12-993-994","DOIUrl":"https://doi.org/10.17073/0368-0797-2018-12-993-994","url":null,"abstract":"Results  of  thermodynamic  modeling  of  the  elements  reduction  from  the  chromium  containing  ore-lime  melt  with  the  use  of  silicon  from ferrosiliconickel as a reducing agent are presented as a function  of temperature. It has been established that an increase in temperature  from  1300  to  2200  °C  helps  to  reduce  the  reduction  degree  of  chromium from 98,9 to 69,8 %.","PeriodicalId":35527,"journal":{"name":"Izvestiya Vysshikh Uchebnykh Zavedenij. Chernaya Metallurgiya","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76280264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"СИЛОВОЙ АНАЛИЗ ПРОЦЕССА ДРОБЛЕНИЯ В КОНУСНОЙ ДРОБИЛЬНОЙ МАШИНЕ","authors":"D. F. Sakharov, А. V. Vitushkin","doi":"10.17073/0368-0797-2018-12-980-986","DOIUrl":"https://doi.org/10.17073/0368-0797-2018-12-980-986","url":null,"abstract":"The literature devoted to cone crushers design and research of  its  crushing  process  is  generally  based  on  empirical  observations,  therefore it is commonly considered that material is crushed under  the  influence  of  squeezing  forces  exclusively.  Above  mentioned  liter  ature, in turn, theoretical base forms for crushing units design.  Based on common understanding, variety of designs of cone crushing  machines  existing  today  is  characterized  by  integrity  of  principles of their work. Majority of theoretical works devoted to cone  crushers are focused on such characteristics as efficiency, extent of  crushing, increase in percent of useful fraction in ultimate product,  or  on  operational  parameters  of  separate  structural  elements  such  as lining armor resistance, increase in endurance of supporting and  power nodes, etc. To increase those characteristics crushing cameras with irregular shape of lining armor are designed, design of an  active  crushing  member  combines  elements  of  active  members  of other crushing machines (roll, cheek crushers). However effectiveness of kinematics of active member movement is considered only  from  the  point  of  view  of  squeezing  forces  generation  in  crushed  material  and  minimization  of  its  slide  against  it.  The  uppermost  ener gy brought to any crushing machines is spent on loa ding destroying crushed material. Authors of this article consider that under  particular  circumstances  such  work  conditions  can  be  provided  in  cone crushers under which energy efficiency of materials crushing  process will increase considerably. One of such conditions is creation  of  multi-axial  stress  in  crushed  material.  Some  reference  designs of cone crushers are considered in the article as well as range  of  their  app lication.  Mechanism  of  multi-axial  stress  generation  in  crushed  material  promoting  decrease  in  energy  consumption  of  crashing  process  is  described.  Recommendations  on  development  of  operating  conditions  of  crushing  machine  creating  multi-axial  stress in crushed material are provided.","PeriodicalId":35527,"journal":{"name":"Izvestiya Vysshikh Uchebnykh Zavedenij. Chernaya Metallurgiya","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84490662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ESTIMATION OF DEFORMABILITY OF HIGH-CARBON STEEL UNDER FORGING","authors":"G. Orlov, Е. N. Shestakova","doi":"10.17073/0368-0797-2018-12-995-996","DOIUrl":"https://doi.org/10.17073/0368-0797-2018-12-995-996","url":null,"abstract":"The article presents high-carbon hypereutectoid steel for production of hot rolling forged rolls. The steel contains 1.2 – 1.4 % of carbon, carbide forming alloying elements Cr, Mo, V and Nb improving  wear  resistance  of  the  rolls,  and  Ni  increasing  hardening  capacity.  It  has  been  found  that  steel  of  proposed  composition  provides  ductility  sufficient  for  hot  deformation  (forging)  by  moderate  single  compressions. Temperature range of ingot deformation has been detected: finite  temperature deformation should not be below 900 °C, forging temperature – 1150 °C. According to its properties steel can be recommended  for manufacturing solid-forged rolls and bandages for composite rolls  of hot rolling from ingots of up to 10 tons weight.","PeriodicalId":35527,"journal":{"name":"Izvestiya Vysshikh Uchebnykh Zavedenij. Chernaya Metallurgiya","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82704715","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ОСОБЕННОСТИ ИЗМЕНЕНИЯ СТРУКТУРЫ И СВОЙСТВ ТВЕРДОФАЗНОГО СОЕДИНЕНИЯ СПЛАВА ОТ4-1, ПОЛУЧЕННОГО ХОЛОДНОЙ ТУГОЙ ПОСАДКОЙ И ПОСЛЕДУЮЩЕЙ ТЕРМИЧЕСКОЙ ОБРАБОТКОЙ","authors":"Павел Вячеславович Бахматов, Василий Илларионович Муравьев, Алексей Валерьевич Фролов, В. С. Пицык","doi":"10.17073/0368-0797-2018-12-963-973","DOIUrl":"https://doi.org/10.17073/0368-0797-2018-12-963-973","url":null,"abstract":"Regularities of the effect of maximum value of stress-strain state,  obtained under conditions of cold forced fit of blanks of the shaft-hole  system during formation of solid-phase diffusion bond (SDB) and subsequent  modes  of  temperature  action  in  autonomous  vacuum,  are  investigated on evolution of structural changes and properties of contact  area  (CA)  of  solid  joints  of  OT4-1  alloy.  It  is  shown  that  under  cold  plastic  deformation  of  OT4-1  alloy,  formation  of  SDB  in  microstructure of CA leads to generation of deformation relief (traces of sliding  along  the  grain  boundaries),  decrease  in  contact  surfaces,  and  to  volume interaction, both in the plane of contact (curvature of grains) and  in  volume  of  contact  zone  (outbreaks  of  dislocations).  The  main  parameters  (specific  parameter  of  structure  organization,  grains  density,  average density of grain boundaries, development of grain boundaries)  exceed  those  of  the  initial  state  of  base  metal  in  10,  4,  1.8,  1.5 times  respectively. Temperature influences under conditions of autonomous  vacuum in the interval of phase transformations α → β lead to staging  of structural changes, both in the main metal and in SDB contact area.  At the initial moment, globular component appears in microstructure,  which  again  goes  back  to  acicular  structure  of  the  initial  state  (with  some  increase  in  microhardness)  with  increase  in  holding  time,  and  also  with  increase  in  temperature.  For  the  first  time,  phenomenon  of  appearance of the globular structure formation stage during heating of  plastically  deformed  metal  is  established  not  only  under  temperature  and  time  conditions  of  phase  transformation,  but  also  under  elevated temperatures; and the higher heating temperature is, the shorter is lifetime  of  the  stage.  Moreover  with  less  degree  of  plastic  deformation,  stage of structure globularization is observed at temperatures close to  T pt and  shorter  exposures.  For  base  metal  (degree  of  deformation  is  insignificant),  globular  structure  disappears  almost  completely  after  heating for 10 min at 950 °C. For stress-strain state of cold-deformed  SDB, globular structure disappears when heated: for 1 hour at 950 °C;  for  40  min  at  975 °C;  for  20  min  at  1000 °С. At  these  temperatures,  process of discontinuities “healing” is almost completed, i.e. bond line  disappears,  and  solid  metal  is  formed  along  the  microstructure  of  the  CA,  not  differing  from  the  basic  metal  with  insignificant  increase  in  microstructure. Quantitative assessment of structural changes in basic  parameters  of  interface  of  structural  state  makes  it  possible  to  reveal  mechanism,  kinetics  and  structural  dependence  on  degree  of  plastic  deformation  and  heat  treatment  regimes,  that  ensure  discontinuities  “healing”,  disappearance  of  interfaces  and  p","PeriodicalId":35527,"journal":{"name":"Izvestiya Vysshikh Uchebnykh Zavedenij. Chernaya Metallurgiya","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84681242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}