Bainitic Cast Irons with Nanosized Particles

2020 ◽  
Vol 994 ◽  
pp. 104-111
Author(s):  
Julieta Atanasova Kaleicheva ◽  
Valentin Plamenov Mishev ◽  
Zdravka Kirilova Karaguiozova
Keyword(s):  
Titanium Nitride ◽  
Abrasive Wear ◽  
Mechanical Characteristics ◽  
Titanium Carbonitride ◽  
Wear Testing ◽  
Nanosized Particles ◽  
Cast Irons ◽  
X Ray ◽  
Bainitic Structure ◽  
Kinetics Of

In the present study austempered ductile irons (ADI) with lower bainitic structure are investigated. Nanosized particles (50nm) of titanium carbonitride + titanium nitride TiCN+TiN and titanium nitride TiN are added to the casting volume. The samples microstructure is studied by optical metallography and X-Ray analysis. The influence of the nanosized additives on the kinetics of the bainitic transformation and on the morphology of the bainitic structure is investigated. The abrasive wear testing, hardness measurements and impact strength are carried out. It is established that the presence of nanoadditives in the bainitic cast irons leads to the changes in their microstructure which increases their mechanical characteristics and abrasive wear resistance. The studied nanocomposite materials expand the potential for new ADI applications in the industry.

scholarly journals INVESTIGATION ON TRIBOLOGICAL BEHAVIOR OF DUCTILE CAST IRONS WITH NANOSIZED PARTICLES

2019 ◽  
Vol 3 ◽  
pp. 84
Author(s):  
Julieta Kaleicheva ◽  
Valentin Mishev ◽  
Manahil Tongov
Keyword(s):  
Wear Resistance ◽  
Cast Iron ◽  
Titanium Nitride ◽  
Tribological Behavior ◽  
Ductile Cast Iron ◽  
Titanium Carbonitride ◽  
Nanosized Particles ◽  
Cast Irons ◽  
Nickel Deposition ◽  
Graphite Phase

The work in this study is focused on investigation of the tribological behavior of ductile cast iron with nanosized particles: titanium nitride TiN; titanium nitride 30% + titanium carbonitride 70% (30%TiN+70%TiCN). The ductile cast iron composition is: Fe-3,55C-2,67Si-0,31Mn-0,009S-0,027P-0,040Cu-0,025Cr-0,08Ni-0,06Mg wt%. Before the addition to the melt nanosized particles were coated with nickel by the electroless nickel deposition method EFFTOMNICKEL .The nickel coating on the nanosized particles ensures their wetting in the melt as well as their uniform distribution into the cast. The optical and quantity metallographic observations and wear test are performed to study the influence of the nanoparticle additives on the cast iron tribological properties. It is observed that the quantity proportion changes between pearlite, ferrite and graphite phase in the cast iron structure. The graphite shape is retained the same, but the nanosized additives decrease the average diameter of the graphite spheres Dmid and increase the quantity of the graphite phase in the structure of ductile cast irons. The cast iron wear resistance in the presence of nanosized additives of (TiN+TiCN) and TiN increases to 55–69% in comparison to wear resistance of the cast iron without nanoparticles.

Effect of Nanoadditives on the Structure and Properties of Austempered Ductile Irons

2018 ◽  
Vol 919 ◽  
pp. 34-42
Author(s):  
Julieta Atanasova Kaleicheva ◽  
Valentin Plamenov Mishev
Keyword(s):  
Impact Toughness ◽  
Cubic Boron Nitride ◽  
Optical Metallography ◽  
Nanosized Particles ◽  
Structure And Properties ◽  
Cast Irons ◽  
X Ray ◽  
Resistance Increase ◽  
Bainitic Structure ◽  
Scanning Electron

In the present study austempered ductile irons (ADI) with an upper and lower bainitic structure with nanosized particles of cubic boron nitride cBN (50nm) are studied. The austempering modes include austenization at 900оС during an hour and isothermal retention at 280оС from 0.5 to 6 hours and at 380oС from 0.5 to 6 hours. The samples microstructure is investigated by means of an optical metallography, scanning electron microscopy and X-ray analysis. Tests for hardness, impact toughness and wear are performed. The influence of nanosized additives on the kinetic of the bainitic transformation and on the morphology of the obtained bainitic structure is studied. It is established that the changes of the bainitic cast irons microstructure under influence of the nanoparticles of cBN lead to the cast irons impact toughness and wear resistance increase. The research is aimed at expanding the scope for new ADI applications in the industry.

New Wear-Resistant Metastable Strain Hardenable Alloyed Cast Irons

2010 ◽  
Vol 457 ◽  
pp. 267-272 ◽  
Author(s):  
Oleksandr P. Cheiliakh ◽  
Irina V. Kolodyazhna
Keyword(s):  
Abrasive Wear ◽  
Raw Materials ◽  
Superficial Layer ◽  
Cast Irons ◽  
Wear Resistant ◽  
Iron And Steel ◽  
X Ray ◽  
Operation Conditions ◽  
Alloyed Cast ◽  
Similar Materials

This work addresses an urgent problem which is saving alloying elements (Ni, Mo, Nb, V, W and others) -which very scarce in Ukraine and other countries- while increasing the physical, mechanical and operational properties of the new designed and developed wear-resistant cast irons. Optical microscopy, x-ray structure analysis, transmission and scanning (fracture) electron microscopy methods, different-thermal, magnetometric and x-ray analyses, as well as hardness and micro-hardness tests, impact energy, and abrasive wear tests in environments of cast-iron shots were employed in the research. The work summarizes the controlling conditions for forming various metastable phases by including deformation (or strain) induced phase transformation (DIPT) and through realization in the process of testing. New wear-resistant economical alloyed cast irons with a metastable austenite-carbide and austenite-martensite-carbide structure are developed, which are being strain- hardened under impact-abrasive wearing operation conditions due to the realization of process DIPT in the superficial layer. These new cast irons are intended for manufacturing parts of different equipment (protective plates of sinter machines, furnaces, tracks for transferring raw materials at iron and steel works, etc.). These cast irons do not contain expensive and deficit alloying components, like nickel, molybdenum, vanadium, and more expensive similar materials. Simultaneously they possess enhanced impact-abrasive wear resistance.

scholarly journals STRUCTURE AND MECHANICAL PROPERTIES OF SPHEROIDAL GRAPHITE CAST IRON WITH NANOSIZED ADDITIVES

2017 ◽  
Vol 3 ◽  
pp. 122 ◽  
Author(s):  
Julieta Kaleicheva ◽  
Valentin Mishev ◽  
Zdravka Karaguiozova ◽  
Galina Nikolcheva
Keyword(s):  
Titanium Nitride ◽  
Cubic Boron Nitride ◽  
Wear Test ◽  
Hardness Measurement ◽  
Sem Analysis ◽  
Titanium Carbonitride ◽  
Metallographic Analysis ◽  
Spheroidal Graphite ◽  
Cast Irons ◽  
Mechanical And Tribological Properties

The microstructure and properties of spheroidal graphite cast irons and austempered ductile irons with nanosized additives of titanium carbonitride and titanium nitride (TiCN+TiN), titanium nitride TiN and cubic boron nitride cBN are investigated. The microstructure of the patterns is observed by optical metallography, quantity metallographic analysis, X-Ray analysis, SEM analysis and EDX analysis. Hardness measurement, impact strength and abrasion wear test on fixed abrasive are performed. The influence of the nanosized additives on the microstructure, mechanical and tribological properties of the cast irons are examined.

GLANCING INCIDENCE X-RAY STUDIES OF TITANIUM NITRIDE THIN FILMS USING A NEW MULTIPURPOSE LABORATORY SPECTROMETER

1989 ◽  
Vol 50 (C7) ◽  
pp. C7-169-C7-173
Author(s):  
R.C BUSCHERT ◽  
P. N. GIBSON ◽  
W. GISSLER ◽  
J. HAUPT ◽  
T. A. CRABB
Keyword(s):  
Thin Films ◽  
Titanium Nitride ◽  
X Ray

In situ Time-Resolved Small-Angle X-ray Scattering Reveals the Formation Kinetics of Polyelectrolyte Complex Micelles

2019 ◽  
Author(s):  
Hao Wu ◽  
Jeffrey Ting ◽  
Siqi Meng ◽  
Matthew Tirrell
Keyword(s):  
Small Angle ◽  
Self Assembly ◽  
Electrostatic Interactions ◽  
Polyelectrolyte Complex ◽  
Time Resolved ◽  
X Ray ◽  
X Ray Scattering ◽  
Kinetics Of ◽  
Ray Scattering

We have directly observed the <i>in situ</i> self-assembly kinetics of polyelectrolyte complex (PEC) micelles by synchrotron time-resolved small-angle X-ray scattering, equipped with a stopped-flow device that provides millisecond temporal resolution. This work has elucidated one general kinetic pathway for the process of PEC micelle formation, which provides useful physical insights for increasing our fundamental understanding of complexation and self-assembly dynamics driven by electrostatic interactions that occur on ultrafast timescales.

scholarly journals Stable and Metastable Phase Equilibria Involving the Cu6Sn5 Intermetallic

2021 ◽  
Author(s):  
A. Leineweber ◽  
M. Löffler ◽  
S. Martin
Keyword(s):  
Phase Equilibria ◽  
Electron Backscatter Diffraction ◽  
Metastable Phase ◽  
Stable Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heat Treated ◽  
Ordered Phases ◽  
Backscatter Diffraction ◽  
Kinetics Of

Abstract Cu6Sn5 intermetallic occurs in the form of differently ordered phases η, η′ and η′′. In solder joints, this intermetallic can undergo changes in composition and the state of order without or while interacting with excess Cu and excess Sn in the system, potentially giving rise to detrimental changes in the mechanical properties of the solder. In order to study such processes in fundamental detail and to get more detailed information about the metastable and stable phase equilibria, model alloys consisting of Cu3Sn + Cu6Sn5 as well as Cu6Sn5 + Sn-rich melt were heat treated. Powder x-ray diffraction and scanning electron microscopy supplemented by electron backscatter diffraction were used to investigate the structural and microstructural changes. It was shown that Sn-poor η can increase its Sn content by Cu3Sn precipitation at grain boundaries or by uptake of Sn from the Sn-rich melt. From the kinetics of the former process at 513 K and the grain size of the η phase, we obtained an interdiffusion coefficient in η of (3 ± 1) × 10−16 m2 s−1. Comparison of this value with literature data implies that this value reflects pure volume (inter)diffusion, while Cu6Sn5 growth at low temperature is typically strongly influenced by grain-boundary diffusion. These investigations also confirm that η′′ forming below a composition-dependent transus temperature gradually enriches in Sn content, confirming that Sn-poor η′′ is metastable against decomposition into Cu3Sn and more Sn-rich η or (at lower temperatures) η′. Graphic Abstract

scholarly journals Kinetics of Network Formation and Heterogeneous Dynamics of an Egg White Gel Revealed by Coherent X-Ray Scattering

2021 ◽  
Vol 126 (9) ◽  
Author(s):  
Nafisa Begam ◽  
Anastasia Ragulskaya ◽  
Anita Girelli ◽  
Hendrik Rahmann ◽  
Sivasurender Chandran ◽  
...  
Keyword(s):  
Network Formation ◽  
Egg White ◽  
X Ray ◽  
X Ray Scattering ◽  
Heterogeneous Dynamics ◽  
Kinetics Of ◽  
Ray Scattering
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