scholarly journals Modelling of nickel aluminide layer growth on IN 738 and Haynes 214 in pack aluminizing

2020 ◽  
Author(s):  
P. Dejthammarong ◽  
P. Visuttipitukul ◽  
S. Leelachao ◽  
S. Pongsugitwat
2014 ◽  
Vol 21 (04) ◽  
pp. 1450053 ◽  
Author(s):  
MIN HUANG ◽  
YU WANG ◽  
MENG-XIAN ZHANG ◽  
YAN-QIU HUO ◽  
PENG-JIN GAO

Low-temperature aluminizing coating was prepared onto the surface of oil casing steel N 80 with a magnetron-sputtered Al film to improve its corrosion resistance. Results show that magnetron-sputtered Al film is able to form gradient aluminide coating, composed of iron aluminide FeAl 3, Fe 2 Al 5 and Fe 3 Al with different contents of aluminum. Both the density and continuity of iron aluminide layer for oil casing steel N 80 with magnetron-sputtered Al film can be improved. Under the same corrosion condition, aluminized oil casing steel N 80 with a magnetron-sputtered Al film shows an outstanding corrosion resistance than those of original and aluminized ones without magnetron-sputtered Al film. The positive effect of Al film is considered as the concentration change of active Al atom for diffusion to form the aluminizing coating during the pack processing.


2011 ◽  
Vol 194-196 ◽  
pp. 232-236
Author(s):  
Min Huang ◽  
Yu Wang ◽  
Xiang Hong Lv

In order to improve the corrosion resistance of pipeline steel X80 and maintain its good mechanical properties simultaneously, a low-temperature pack aluminizing process was carried out at 723 K on pipeline steel X80 after a surface mechanical attrition treatment (SMAT). The phase composition, microstructure and element distribution of the as-aluminized pipeline steel X80 were characterized by XRD, SEM and EDS, respectively.The results show that the as-received aluminide layer consists of Fe2Al5, which exhibits a good cohesion with SMATed pipeline steel X80 substrate with the thickness of around 90 μm. The element concentrations of Al and Fe atoms show a gradual change in the range of aluminide layer. After corrosion test processed in 3.5% NaCl solution, there is no obvious corrosion crack or uphills piled up by corrosion products on the surface of as-aluminized SMATed pipeline steel, which can conclude that pack aluminizing assisting by SMAT at low-temperature is an effective way for protecting pipeline steel X80 against corrosion.


Metals ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 648 ◽  
Author(s):  
Xing Wang ◽  
Yongzhe Fan ◽  
Xue Zhao ◽  
An Du ◽  
Ruina Ma ◽  
...  

Pack aluminizing of spheroidal graphite cast iron with different aluminizing temperature and time was studied. Results showed that the thickness of aluminized layer increased with the increasing temperature and time. The optimized process parameters are as follow: the aluminizing packed temperature is 830 °C and the time is 3 h. The aluminized layer consisted of the inner FeAl and the outer Fe2Al5. Some graphite nodules were observed in the aluminide layer after aluminizing. The mass gain of the aluminized cast iron was 0.405 mg/cm2, being 1/12 of the untreated substrate after oxidation. The high temperature oxidation resistance can be improved effectively by pack aluminizing, even though there were graphite nodules in the aluminide layer.


2003 ◽  
Vol 780 ◽  
Author(s):  
P. Thomas ◽  
E. Nabighian ◽  
M.C. Bartelt ◽  
C.Y. Fong ◽  
X.D. Zhu

AbstractWe studied adsorption, growth and desorption of Xe on Nb(110) using an in-situ obliqueincidence reflectivity difference (OI-RD) technique and low energy electron diffraction (LEED) from 32 K to 100 K. The results show that Xe grows a (111)-oriented film after a transition layer is formed on Nb(110). The transition layer consists of three layers. The first two layers are disordered with Xe-Xe separation significantly larger than the bulk value. The third monolayer forms a close packed (111) structure on top of the tensile-strained double layer and serves as a template for subsequent homoepitaxy. The adsorption of the first and the second layers are zeroth order with sticking coefficient close to one. Growth of the Xe(111) film on the transition layer proceeds in a step flow mode from 54K to 40K. At 40K, an incomplete layer-by-layer growth is observed while below 35K the growth proceeds in a multilayer mode.


2018 ◽  
Vol 49 (15) ◽  
pp. 1445-1458
Author(s):  
Deheng Shi ◽  
Fenghui Zou ◽  
Zunlue Zhu ◽  
Jinfeng Sun

1999 ◽  
Vol 567 ◽  
Author(s):  
Renee Nieh ◽  
Wen-Jie Qi ◽  
Yongjoo Jeon ◽  
Byoung Hun Lee ◽  
Aaron Lucas ◽  
...  

ABSTRACTBa0.5Sr0.5TiO3 (BST) is one of the high-k candidates for replacing SiO2 as the gate dielectric in future generation devices. The biggest obstacle to scaling the equivalent oxide thickness (EOT) of BST is an interfacial layer, SixOy, which forms between BST and Si. Nitrogen (N2) implantation into the Si substrate has been proposed to reduce the growth of this interfacial layer. In this study, capacitors (Pt/BST/Si) were fabricated by depositing thin BST films (50Å) onto N2 implanted Si in order to evaluate the effects of implant dose and annealing conditions on EOT. It was found that N2 implantation reduced the EOT of RF magnetron sputtered and Metal Oxide Chemical Vapor Deposition (MOCVD) BST films by ∼20% and ∼33%, respectively. For sputtered BST, an implant dose of 1×1014cm−;2 provided sufficient nitrogen concentration without residual implant damage after annealing. X-ray photoelectron spectroscopy data confirmed that the reduction in EOT is due to a reduction in the interfacial layer growth. X-ray diffraction spectra revealed typical polycrystalline structure with (111) and (200) preferential orientations for both films. Leakage for these 50Å BST films is on the order of 10−8 to 10−5 A/cm2—lower than oxynitrides with comparable EOTs.


Processes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 306
Author(s):  
Kazuya Taira ◽  
Tomonori Waku ◽  
Yoshimichi Hagiwara

The control of ice growth inside channels of aqueous solution flows is important in numerous fields, including (a) cold-energy transportation plants and (b) the preservation of supercooled human organs for transplantation. A promising method for this control is to add a substance that influences ice growth in the flows. However, limited results have been reported on the effects of such additives. Using a microscope, we measured the growth of ice from one sidewall toward the opposite sidewall of a mini-channel, where aqueous solutions of sodium chloride and antifreeze protein flowed. Our aim was to considerably suppress ice growth by mixing the two solutes. Inclined interfaces, the overlapping of serrated interfaces, and interfaces with sharp and flat tips were observed in the cases of the protein-solution, salt-solution, and mixed-solution flows, respectively. In addition, it was found that the average interface velocity in the case of the mixed-solution flow was the lowest and decreased by 64% compared with that of pure water. This significant suppression of the ice-layer growth can be attributed to the synergistic effects of the ions and antifreeze protein on the diffusion of protein.


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