scholarly journals Study of Recrystallization Kinetics of 1565ch Aluminum Alloy during hot deformation

2020 ◽  
Vol 326 ◽  
pp. 05001
Author(s):  
Vasiliy Yashin ◽  
Alexander Drits ◽  
Evgenii Aryshenskii ◽  
Ilya Latushkin ◽  
Ekaterina Chitnaeva
Keyword(s):  
Growth Rate ◽  
Aluminum Alloy ◽  
Optical Microscope ◽  
Recrystallization Process ◽  
System Alloy ◽  
Industrial Practice ◽  
Cast Ingot ◽  
Recrystallization Kinetics ◽  
Different Temperatures ◽  
Kinetics Of

The present study addresses recrystallization process in Al-Mg-Mn-Zn-Zr system alloy samples. The samples are collected from cast ingot, produced by casting to industrial DC mold, and homogenized based on standard industrial practice. After that the samples were rolled with different hot rolling schedules. Rolled samples were annealed at different temperatures and their resultant microstructure was examined using optical microscope. During the study new grains nuclei generation rate and their growth rate were determined, analytical records, describing recrystallization kinetics, were obtained, main differences, specific to this alloy recrystallization in 350 ºС-450 ºС temperature range, were identified.

Recrystallization of 304SS during and after High Strain Rate Deformation

2013 ◽  
Vol 753 ◽  
pp. 403-406
Author(s):  
Adam S. Taylor ◽  
Peter D. Hodgson
Keyword(s):  
Dynamic Recrystallization ◽  
Strain Rate ◽  
Austenitic Stainless Steels ◽  
Avrami Equation ◽  
Recrystallization Process ◽  
Hollomon Parameter ◽  
Softening Mechanism ◽  
Recrystallization Kinetics ◽  
Kinetics Of ◽  
Shape Changes

During the hot working of austenitic stainless steels the shape of the flow curve is strongly influenced by the strain rate. Low strain rate deformation results in flow curves typical of dynamic recrystallization (DRX) but as the strain rate increases the shape changes to a ‘flat-top’ curve. This has traditionally been thought to indicate no DRX is taking place and that dynamic recovery (DRV) is the only operating softening mechanism. Examining the work-hardening behaviour and corresponding deformation microstructures showed this is not the case for austenitic stainless steel, as clear evidence of dynamic recrystallization process can be seen. The post-deformation recrystallization kinetics can be modelled using a standard Avrami equation with an Avrami exponent, n, of 1.15. With an increasing value of the Zener-Hollomon parameter it was found that the kinetics of recrystallization become less strain rate sensitive until at the highest values (highest strain rates/lowest temperatures) the recrystallization kinetics become strain rate insensitive.

SOĞUK HADDELENMİŞ AA3105 VE AA5005 LEVHALARIN DSC ANALİZİ İLE YENİDEN KRİSTALLENME KİNETİĞİ

2021 ◽  
Vol 8 (17) ◽  
pp. 80-85
Author(s):  
Atae RAOUGUI ◽  
Ion GRECU ◽  
Volkan Murat YILMAZ ◽  
Kenan YILDIZ
Keyword(s):  
Differential Scanning Calorimetry ◽  
Aluminum Alloy ◽  
Activation Energies ◽  
Isothermal Kinetics ◽  
Heating Rates ◽  
Scanning Calorimetry ◽  
Recrystallization Kinetics ◽  
Model Free ◽  
Cold Rolled ◽  
Kinetics Of

In this study, the non-isothermal recrystallization kinetics of cold rolled AA3105 and AA5005 aluminum alloy sheets obtained from ASAŞ Aluminum located in Akyazı-Sakarya was studied by using differential scanning calorimetry (DSC). The non – isothermal kinetics was performed by using Kissenger, Boswell, Ozawa and Starink methods known as model – free methods. The recrystallization temperatures on DSC graphics at different heating rates (β) were deduced and the activation energies were calculated from the slopes from Y – 1/T diagrams. Y is ln(β/T2) for Kissenger, ln(β/T) for Boswell, ln(β) for Ozawa and ln(β/T1.92) for Starink. The results showed that the activation energies of recrystallization are in the range of 194 – 206 kJ/mol for cold rolled AA5005 sheet and in the range of 235 – 257 kJ/mol for cold rolled AA3105 sheet, according to four non-isothermal kinetics model.

Dynamic recrystallization kinetics of 42CrMo steel during compression at different temperatures and strain rates

2011 ◽  
Vol 528 (13-14) ◽  
pp. 4643-4651 ◽  
Author(s):  
Guo-Zheng Quan ◽  
Gui-Sheng Li ◽  
Tao Chen ◽  
Yi-Xin Wang ◽  
Yan-Wei Zhang ◽  
...  
Keyword(s):  
Dynamic Recrystallization ◽  
Strain Rates ◽  
Recrystallization Kinetics ◽  
42Crmo Steel ◽  
Different Temperatures ◽  
Kinetics Of

scholarly journals Effects of Widening during Rolling on the Subsequent Recrystallization Kinetics of Copper

2013 ◽  
Vol 753 ◽  
pp. 285-288
Author(s):  
Feng Xiang Lin ◽  
Torben Leffers ◽  
Wolfgang Pantleon ◽  
Dorte Juul Jensen
Keyword(s):  
Recrystallization Texture ◽  
Electron Backscatter Diffraction ◽  
Cube Texture ◽  
Recrystallization Process ◽  
Recrystallization Kinetics ◽  
Two Samples ◽  
Electron Backscatter ◽  
Cold Rolled ◽  
Backscatter Diffraction ◽  
Kinetics Of

Recrystallization kinetics in copper cold-rolled to 90% reduction with and without significant widening was investigated by electron backscatter diffraction. It was found that the recrystallization process was slightly retarded and the development of cube recrystallization texture was largely inhibited in the widening sample. Cube grains were observed to have a growth advantage by a factor of 2 in the non-widening sample, while this growth advantage was not observed in the widening sample. The recrystallization kinetics and the development of cube texture in the two samples are discussed.

The Influence of Strain on Semi-Solid Behavior in AC4C Aluminum Alloy Billet by One Way Torsion Working

2006 ◽  
Vol 15-17 ◽  
pp. 35-40
Author(s):  
Norihisa Sugie ◽  
Mitsuaki Furui ◽  
Hiroshi Anada
Keyword(s):  
Aluminum Alloy ◽  
Eutectic Temperature ◽  
Optical Microscope ◽  
Recrystallization Process ◽  
Dendrite Structure ◽  
Microstructure Observation ◽  
Α Phase ◽  
Single Side ◽  
Solid Region ◽  
Semi Solid

This study was investigated about that behavior of α phase during recrystallization process and the influence of the amount of strain on semi-solid structure of AC4C aluminum alloy which was processed by one way torsion working. AC4C aluminum alloy billets having a diameter of 35mm and a length of 400mm were torsioned by a single side torsion machine. The maximum strain (γmax) of the specimens in this experiment was 0.88. The specimens were etched for the microstructure observation by optical microscope. The casting material (γ＝0) and the torsion material (γ＝0.73) were remained dendrite structure from room temperature to 565°C. The casting materials had grain-shaped structure when they reached to 585°C which is an eutectic temperature in this alloy. However the torsion working material had it when they reached to 577°C from eutectic temperature on down. In semi-solid region, the structure of the torsion working material was finer than that of casting material and became a more grain-shaped structure. The casting material which was heated to the eutectic temperature was changed to dendrite structure again. However the torsion working material was remained grain-shaped structure.

scholarly journals Wetting Kinetics and Microstructure Analysis of BNi2 Filler Metal over Selective Laser Melted Ti-6Al-4V Substrate

Materials ◽  
2020 ◽  
Vol 13 (20) ◽  
pp. 4666
Author(s):  
Jiankun Liu ◽  
Guanpeng Liu ◽  
Hua Ouyang ◽  
Yulong Li ◽  
Ming Yan ◽  
...  
Keyword(s):  
Filler Metal ◽  
Optical Microscope ◽  
Promoting Effect ◽  
Tc4 Titanium Alloy ◽  
Initial Stage ◽  
Different Temperatures ◽  
Three Stages ◽  
Wetting Kinetics ◽  
Kinetics Of

The wetting kinetics of nickel-based filler metal (BNi2) over selective laser-melted Ti-6Al-4V (SLMed TC4) titanium alloy in a protective argon atmosphere is experimentally investigated using a real-time in situ hot stage equipped with an optical microscope. The spreading processes at different temperatures are similar, and the overall wetting/spreading process can be roughly divided into three stages: (i) an initial stage, (ii) a rapid spreading stage, and (iii) an asymptotic stage. Moreover, the wetting kinetics of the BNi2/SLMed TC4 system can be expressed by empirical power exponential function Rn~t with n = ~1. In the process of spreading, Ti-based solid solution (Ti(ss)) and intermetallic compound (Ti2Ni and TiB2) were formed at the interface within the reaction domain, and the phase transition of α’ martensitic to α-Ti and β-Ti also took place. The influence of elevated temperature on the spreading and wetting kinetics of the BNi2/SLMed TC4 system was studied, and the results show that the increase of temperature has a slightly promoting effect on the spreading, but a limited impact on the value of n. In addition, the spreading and wetting kinetics of BNi2/SLMed TC4 system are similar to those of BNi2 on conventional forged TC4 substrate.

Kinetics of Solidification at Rapid Rates

1983 ◽  
Vol 28 ◽  
Author(s):  
S.D. Peteves ◽  
J. Alvarez ◽  
G.J. Abbaschian
Keyword(s):  
Growth Rate ◽  
Optical Microscope ◽  
Interface Temperature ◽  
Lateral Growth ◽  
Single Nucleus ◽  
Temperature And Growth ◽  
Straight Lines ◽  
Solid Liquid ◽  
Free Interfaces ◽  
Kinetics Of

ABSTRACTA novel technique was used to measure directly the interface temperature and growth rate during solidification of pure gallium. The technique utilizes the Seebeck emf generated across two solid-liquid interfaces to determine the interface supercooling and an optical microscope to measure the solidification rates. The growth rate measurements were made in the range of about 0.08 to 1400 μm/s for 1.59 to 3.6°C interface supercoolings (ΔT) on the (111) interface of high purity gallium in glass capillaries. A plot of logv vs. 1/T for dislocation-free interfaces followed two straight lines, one for higher than about 1 μm/s growth rates and the other for the lower rates. The data at the lower rates correspond to the lateral growth mechanism for which a single nucleus forms and spreads across the interface before formation of the next nucleus, while those at the higher solidification rates correspond to the lateral growth by the multi-nucleation and spreading mechanism.

scholarly journals Growth Modeling Kinetics of Aspergillus flavus in Dried Jujube at Different Temperatures

2021 ◽  
Author(s):  
Yiming Guo ◽  
Hua Ji
Keyword(s):  
Growth Rate ◽  
Growth Kinetic ◽  
Lag Time ◽  
Growth Characteristics ◽  
Optimal Temperature ◽  
Different Temperatures ◽  
Lag Period ◽  
Storage Methods ◽  
Kinetics Of

Dried jujube is a characteristic fruit of Xinjiang. Aspergillus is one of the main pathogens that causes mold on dried jujube, and A. flavus is a toxin-producing species, the aflatoxin produced by A. flavus is extremely toxic and carcinogenic. In this study, the growth kinetic models of A. flavus isolated from red jujube at different temperatures and times were fitted to Huang model and linear equation respectively, the Cardinal model was used to describe the growth rate and lag time of A. flavus on dried jujube agar. It turned out that 30–35 °C was the optimal temperature for growing A. flavus, so dried jujube should avoid storing in this temperature range. The kinetic model established in this study will help to understand the growth characteristics of A. flavus, and lay a foundation for evaluating the quality of stored dried jujube and predictions of shelf life, which are conducive to optimizing storage methods for dried jujube. It can be judged according to the value of Af and Bf, the Huang model had a better fitting effect than the Baranyi model, The two models all had the highest growth rate at 35 °C, and A. flavus grew more vigorously and the lag period shortened as the temperature was increased. The secondary Cardinal model had a good fitting effect on the growth rate and lag time, and the secondary Ratkowsky model had a good fitting effect on the growth rate. This study may have theoretical and application value to strengthen the safety of jujube storage in the future.

Sign in / Sign up

Export Citation Format

Share Document