The Effect of High Temperature Grain Refinement on the Isothermal Ferrite Grain Growth Kinetics in Steel S460

2012 ◽  
Vol 715-716 ◽  
pp. 907-912 ◽  
Author(s):  
J.S. Hinton ◽  
Eric J. Palmiere ◽  
W.M. Rainforth
Keyword(s):  
High Temperature ◽  
Growth Kinetics ◽  
True Strain ◽  
Plate Steel ◽  
Transformation Kinetics ◽  
Industrial Processing ◽  
Processing History ◽  
Series Of Experiments ◽  
Grain Growth Kinetics

Plate steel S460 is intercritically rolled during the final stages of industrial processing. A series of experiments to represent the preliminary stages of an intercritical simulation were completed and the isothermal austenite to ferrite transformation kinetics investigated. The growth of the ferrite grains was interpreted using the classic JMAK model and the effect of processing history also examined. A double austenite deformation at 1323 K, to a true strain of 0.2, led to the most acceptable starting microstructure for the extended simulation. The role of niobium in this preliminary simulation is also considered.

scholarly journals Determination of Grain Growth Kinetics and Assessment of Welding Effect on Properties of S700MC Steel in the HAZ of Welded Joints

Metals ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 707 ◽  
Author(s):  
Jaromir Moravec ◽  
Iva Novakova ◽  
Jiri Sobotka ◽  
Heinz Neumann
Keyword(s):  
High Temperature ◽  
Grain Growth ◽  
Growth Kinetics ◽  
Welded Joints ◽  
Material Constant ◽  
Temperature Cycle ◽  
Vacuum Furnace ◽  
Testing Procedures ◽  
Temperature Cycles ◽  
Grain Growth Kinetics

The welding of fine-grained steels is a very specific technology because of the requirement for the heat input limit value. Applying temperature cycles results in an intense grain growth in a high-temperature heat-affected zone (HAZ). This has a significant effect on the changing of strength properties and impact values. The intensity of grain coarsening in the HAZ can be predicted based on the experimentally determined activation energy and material constant, both of which define grain growth kinetics. These quantities, together with real measured welding cycles, can be subsequently used during experiments to determine mechanical properties in a high-temperature HAZ. This paper shows a methodical procedure leading to the obtainment of the material quantities mentioned above that define the grain growth, both at fast and slow temperature cycles. These data were used to define the exposure temperature and the soaking time in a vacuum furnace to prepare test samples with grain sizes corresponding to the high-temperature HAZ of welded joints for the testing procedures. Simultaneously, by means of the thermo-mechanical simulator Gleeble 3500, testing samples were prepared which, due to a temperature gradient, created conditions comparable to those in the HAZ. The experiments were both carried out with the possibility of free sample dilatation and under a condition of zero dilation, which happens when the thermal expansion of a material is compensated by plastic deformation. It has been found that shape of the temperature cycle, maximal achieved cycle temperature, cooling rate, and, particularly, the time in which the sample is in the austenite region have significant effects on the resulting change of properties.

Growth kinetics of O-polar BexMgyZn1-x-yO alloy: Role of Zn to Be and Mg flux ratio as a guide to growth at high temperature

2017 ◽  
Vol 121 (18) ◽  
pp. 185704 ◽  
Author(s):  
M. B. Ullah ◽  
V. Avrutin ◽  
T. Nakagawara ◽  
S. Hafiz ◽  
I. Altuntaş ◽  
...  
Keyword(s):  
High Temperature ◽  
Growth Kinetics ◽  
Flux Ratio ◽  
Kinetics Of ◽  
Role Of Zn

Study of Grain Growth Kinetics in Submicrocrystalline Armco-Iron

2007 ◽  
Vol 550 ◽  
pp. 465-470 ◽  
Author(s):  
A.N. Aleshin ◽  
Alex M. Arsenkin ◽  
Sergey V. Dobatkin
Keyword(s):  
Thermal Stability ◽  
High Temperature ◽  
Low Temperature ◽  
Grain Growth ◽  
Growth Kinetics ◽  
Armco Iron ◽  
High Temperature Annealing ◽  
Grain Growth Kinetics ◽  
Submicrocrystalline Materials ◽  
Thermal Stability Of

The paper is devoted to the problem of thermal stability of ultra-fine grained (submicrocrystalline) materials prepared by severe plastic deformation. A basis of the paper lies in a fact that there is practically no grain growth in submicrocrystalline materials when annealing temperature is less than 0.35Tm. Reasons of high thermal stability of submicrocrystalline materials at low temperatures are widely discussed in literature. One of them is the affect of triple junction drag on grain boundaries motion. During annealing at a low temperature triple junction drag controls microstructure evolution in submicrocrystalline materials, and this phenomenon can be used to improve their thermal stability at high temperatures. The aim of this paper is to investigate grain growth kinetics in a two-step regime, low temperature and high temperature annealing. The experiments on grain growth were performed in submicrocrystalline Armco-iron fabricated by high pressure torsion. It is established that long-time low temperature pre-annealing reduces the grain growth rate in following high temperature annealing by a factor greater than two.

The Ordered Phase Formation in Ti-Al-Ga Alloys

1970 ◽  
Vol 28 ◽  
pp. 440-441
Author(s):  
Shiro Fujishiro ◽  
Harold L. Gegel
Keyword(s):  
Thermal Stability ◽  
High Temperature ◽  
Titanium Alloys ◽  
Growth Kinetics ◽  
Stoichiometric Composition ◽  
Good Potential ◽  
Alpha Titanium ◽  
Cold Rolled ◽  
Kinetics Of ◽  
Thermal Stability Of

Ordered-alpha titanium alloys having a DO19 type structure have good potential for high temperature (600°C) applications, due to the thermal stability of the ordered phase and the inherent resistance to recrystallization of these alloys. Five different Ti-Al-Ga alloys consisting of equal atomic percents of aluminum and gallium solute additions up to the stoichiometric composition, Ti3(Al, Ga), were used to study the growth kinetics of the ordered phase and the nature of its interface.The alloys were homogenized in the beta region in a vacuum of about 5×10-7 torr, furnace cooled; reheated in air to 50°C below the alpha transus for hot working. The alloys were subsequently acid cleaned, annealed in vacuo, and cold rolled to about. 050 inch prior to additional homogenization

scholarly journals The Role of Chromium in Iron-based High-Temperature Water-Gas Shift Catalysts under Industrial Conditions

2021 ◽  
pp. 120465
Author(s):  
M.I. Ariëns ◽  
V. Chlan ◽  
P. Novák ◽  
L.G.A. van de Water ◽  
A.I. Dugulan ◽  
...  
Keyword(s):  
High Temperature ◽  
Water Gas Shift ◽  
High Temperature Water ◽  
Iron Based ◽  
Water Gas ◽  
Temperature Water
Sign in / Sign up

Export Citation Format

Share Document