Effects of Aluminizing on the High Temperature Oxidation Behavior of High Silicon Cast Iron

2009 ◽  
Vol 79-82 ◽  
pp. 2151-2154
Author(s):  
Meng Bin Lin ◽  
Chaur Jeng Wang
Keyword(s):  
Cast Iron ◽  
High Temperature ◽  
High Temperature Oxidation ◽  
Temperature Oxidation ◽  
Outward Diffusion ◽  
X Ray ◽  
Oxygen Penetration ◽  
Coating Layers ◽  
High Silicon ◽  
High Temperature Oxidation Behavior

In this study, the aluminizing of high silicon cast iron by hot-dipping in pure Al melt was performed and their high temperature oxidation behaviour was tested at 750 °C for virous exposure time. After high temperature oxidation tests, the microstructure analysis of all samples were investigated by means of metallographical examination, scanning electron microscopy (SEM) equipped with energy-dispersive X-ray spectrometer (EDS) and X-ray diffractometry (XRD).The results showed that the coating layers consisted of three layer, in the sequence of Al, Fe-Al and Si-rich layers from external topcoat to substrate. Nodules graphite had a blocking effect to retard the outward diffusion of Fe atoms and impeded the growth of Fe2Al5 in C-axis. Eventually, the cast iron substrate was oxidized directly by oxygen penetration via the greater cracks and pores to form Fe oxide nodules after 750 °C oxidation for 48h.

High Temperature Oxidation Behavior of Arc-sprayed FeCrBAlMo Coating

2016 ◽  
Vol 19 (1) ◽  
Author(s):  
Xin Zhang ◽  
Zehua Wang ◽  
Jinran Lin
Keyword(s):  
High Temperature ◽  
High Temperature Oxidation ◽  
Oxidation Behavior ◽  
Steel Substrate ◽  
Arc Spraying ◽  
X Ray Diffraction ◽  
Temperature Oxidation ◽  
X Ray ◽  
High Velocity Arc Spraying ◽  
High Temperature Oxidation Behavior

AbstractFeCrBAlMo coating was deposited on an AISI 20 steel substrate by high velocity arc spraying (HVAS). Compared with FeCrBSiMo coating and pristine AISI 20 steel, the microstructure and high temperature oxidation behavior of FeCrBAlMo coating were investigated by optical microscopy, scanning electron microscopy, energy-dispersive spectroscopy and X-ray diffraction. Meanwhile, the bonding strength of the coatings was also measured. The results indicated that both coatings were composed of α(Fe,Cr) and Fe

scholarly journals High Temperature Oxidation Behavior of an Equimolar Cr-Mn-Fe-Co High-Entropy Alloy

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4259
Author(s):  
Lin Wang ◽  
Quanqing Zeng ◽  
Zhibao Xie ◽  
Yun Zhang ◽  
Haitao Gao
Keyword(s):  
High Temperature ◽  
Oxide Layer ◽  
High Temperature Oxidation ◽  
Oxidation Behavior ◽  
High Entropy Alloy ◽  
Spinel Type ◽  
Temperature Oxidation ◽  
Outward Diffusion ◽  
High Entropy ◽  
High Temperature Oxidation Behavior

The oxidation behavior of an equimolar Cr-Mn-Fe-Co high-entropy alloy (HEA) processed by 3D laser printing was investigated at 700 °C and 900 °C. The oxidation kinetics of the alloy followed the parabolic rate law, and the oxidation rate constant increased with the rising of the temperature. Inward diffusion of oxygen and outward diffusion of cations took place during the high-temperature oxidation process. A spinel-type oxide was formed on the surface, and the thickness of the oxide layer increased with the rising of experimental temperature or time. The exfoliation of the oxide layer took place when the test was operated at 900 °C over 12 h. During oxidation tests, the matrix was propped open by oxides and was segmented into small pieces. The formation of loose structures had great effects on the high-temperature oxidation resistance of the HEA.

scholarly journals High-Temperature Oxidation Behavior of Fe–1Cr–0.2Si Steel

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 509
Author(s):  
Mingxin Hao ◽  
Bin Sun ◽  
Hao Wang
Keyword(s):  
High Temperature ◽  
Iron Oxide ◽  
High Temperature Oxidation ◽  
Oxidation Behavior ◽  
Steel Tube ◽  
Temperature Oxidation ◽  
Outward Diffusion ◽  
High Temperature Oxidation Behavior ◽  
Mixed Layers ◽  
Oxidation Weight Gain

In the case of Fe–1Cr–0.2Si steel, tube furnace oxidation was carried out for 120 min and 30 min. These studies, along with the high-temperature oxidation behavior of Fe–1Cr–0.2Si steel, were examined from 700 to 1100 °C. It has been observed that with an increase in the oxidation time, the oxidation weight gain per unit area of Fe–1Cr–0.2Si steel changed from a linear to a parabolic relationship. The time was shortened when the oxidation phase was linear. When the oxidation temperature exceeded 900 °C, the value of WTransition decreased, and the oxidation rule changed. It could be considered that overall, the iron oxide structure of Fe–1Cr–0.2Si steel is divided into two layers. The formation of an outer oxide of iron is mainly caused by the outward diffusion of cation, while the inward diffusion of O ion forms the inner oxides of chromium and silicon. As the temperature increases, the thickness of the outer iron oxide gradually increases, and the thickness ratio of the inner mixed layers of chromium- and silicon-rich oxides decreases; however, the degree of enrichment of Cr and Si in the mixed layer increases. After high-temperature oxidation, Cr and Si did not form a composite oxide but were mechanically mixed in the form of FeCr2O4 and Fe2SiO4, and no significant delamination occurred.

High Temperature Oxidation Behavior of Si-Mo Ferritic Ductile Cast Iron

2010 ◽  
Vol 654-656 ◽  
pp. 542-545 ◽  
Author(s):  
Kyeong Hwan Choe ◽  
Sang Mok Lee ◽  
Kyong Whoan Lee
Keyword(s):  
Cast Iron ◽  
High Temperature ◽  
Oxide Layer ◽  
Test Temperature ◽  
High Temperature Oxidation ◽  
Oxidation Behavior ◽  
Ductile Cast Iron ◽  
Ferrous Alloy ◽  
Temperature Oxidation ◽  
High Temperature Oxidation Behavior

High temperature oxidation behavior of Si-Mo ferritic ductile cast iron was investigated in the point of the effect of chromium and vanadium addition. The addition of Cr promoted the formation of as-cast pearlite around carbide which exists in cell boundary, which was eliminated during annealing process. The addition of vanadium promoted the precipitation of tiny carbide and reduced the grain size of ferrite. As the test temperature increased, the change of volume increased, on the other hand, the change of weight decreased above 1173K. In the case of Cr added specimen, the change of weight decreased with the increase of test temperature because of the presence of Cr oxide layer. The vanadium added specimens showed higher increase in the weight and volume change. The oxide layer of vanadium added specimen had very porous structure and showed severe internal oxidation. It is due to the catastrophic oxidation characteristic of vanadium alloyed ferrous alloy.

High Temperature Oxidation Behavior of ZrB2-SiC-Graphite Composite Heated by High Electric Current

2010 ◽  
Vol 105-106 ◽  
pp. 162-164
Author(s):  
Hong Bo Chen ◽  
Song He Meng
Keyword(s):  
High Temperature ◽  
Electric Current ◽  
High Temperature Oxidation ◽  
Oxidation Behavior ◽  
X Ray Diffraction ◽  
Temperature Oxidation ◽  
Graphite Composite ◽  
X Ray ◽  
High Temperature Oxidation Behavior ◽  
Oxidation Testing

High temperature oxidation testing was carried out on hot-pressed ZrB2-SiC-graphite composite by using high electric current heating. The composites oxidation behavior was investigated, the temperature of oxidized specimens was above 2000°C. The results found that the UHTC composite was ruptured at oxidized temperature 2055°C. The microstructure of surface and cross-section of posttest samples were investigated by scanning electron microscopy along with energy and X-ray diffraction. The failure mechanism of rupture was also discussed.

Effect of WС Content on the Mechanical Properties and High Temperature Oxidation Behavior of Ti(С,N)-Based Cermets

2018 ◽  
Vol 274 ◽  
pp. 9-19
Author(s):  
Guo Tao Zhang ◽  
Yong Zheng ◽  
Yi Jie Zhao ◽  
Wei Zhou ◽  
Jia Jie Zhang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
High Temperature ◽  
High Temperature Oxidation ◽  
Isothermal Oxidation ◽  
Oxide Scales ◽  
X Ray Diffraction ◽  
Temperature Oxidation ◽  
X Ray ◽  
Oxidation Rates ◽  
High Temperature Oxidation Behavior

Ti (C,N)-based cermets with varying WC additions (Ti (C0.6N0.4)-36Ni-12Mo-1C-xWC, x = 0, 3, 6 and 9 wt%) were prepared by conventional powder metallurgy techniques. The microstructure and mechanical properties of all four Ti (C,N)-based cermets were investigated. Isothermal oxidation of all four cermets were also investigated in air at 800°C up to 100 h using scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and X-ray diffraction analysis (XRD). The grains of Ti (C,N)-based cermets became more homogeneous with the increase of WC content. The TRS and fracture toughness increased with the increase of WC content and then decreased when WC content exceeded 6wt%, but hardness decreased continuously with the increase of WC content. The oxide scales formed on the surface of all four samples during the oxidation process were porous and multi-layered, consisting of NiO outerlayer and TiO2 based innerlayer, respectively. The thickness of the oxide scales and oxidation rates increased with the increase of WC content, especially when the content of WC addition reached 9wt%. The cermet with 6wt% WC addition showed excellent mechanical properties and acceptable high temperature oxidation resistance.

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