CERAMICS INTERNATIONAL
·
2015
·
IF 2.605
Yu Hui,Sumei Zhao,Jiaying Xu,Binglin Zou,Ying Wang,Xiaolong Cai,Ling Zhu,Xueqiang Cao
Degradation due to molten salt attack is one of the failure mechanisms of thermal barrier coatings . Thermochemical attack of the salt mixture Na 2 SO 4 –30 mol% NaVO 3 on ZrO 2 –8 mol% YO 1.5 (8YSZ) at 1100 °C for different times was investigated. In the present study, 8YSZ powder was synthesized using co-precipitation route. The graded morphologies and phase compositions were examined using SEM, XRD and Raman before and after hot corrosion test. The results obtained from XRD have shown that m-ZrO 2 and YVO 4 were the main corrosion products after hot corrosion test at 1100 °C. The results obtained from SEM and EDS observations have shown that large polyhedron crystals of m-ZrO 2 and rod-like crystals of YVO 4 formed as hot corrosion products after hot corrosion test for 6 h and 24 h. The phase transformation and chemical interaction are the primary corrosion mechanisms for degradation of 8YSZ ceramic.
研究领域:
材料科学
·
腐蚀与防护
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Sun Jiaqi,Peng Yaru,Chen Zeng
Applications of the molten salt electrodeposition method have attracted researcher’s attention in the preparation of magnesium-based alloys in the past decades. Sometimes, hot corrosion occurs on the surface of a metal electrode in molten salt. Here, the corrosion of a Ni electrode and its effect on the electrochemical formation processes of Mg-Ni alloys were studied in LiCl-KCl-MgCl 2 molten salt under an Ar atmosphere. Immersion experiments and some electrochemical experiments, such as cyclic voltammetry (CV), open-circuit chronopotentiometry (OCP), and potentiostatic electrolysis, were carried out to investigate the performance of a Ni metal electrode in LiCl-KCl-MgCl 2 molten salt. Hot corrosion of the Ni electrode became serious with the addition of MgCl 2 , and MgO was deposited on the surface of the Ni sheet. The CV and OCP experiments showed that the water introduced from outside had serious effects on the electrochemical reaction processes in this experiment. Corrosion of the Ni substrate was dynamically and thermodynamically inhibited in the electrochemical formation processes of Mg-Ni alloys. However, there was a small amount of MgO in the Mg-Ni alloys, and corrosion of the Ni sheet showed obvious effects on the morphology of Mg-Ni alloys
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Jun Wang,Jianbo Song,Chunyu Jiang,Xing Yang,Jianyu Li,Zifan Zhao,Peng Wu,Xiaoyu Chong,Jing Feng
To protect carbon/carbon composites against thermal corrosion and high-temperature oxidation , the thermal/oxygen barrier properties and static oxidation behavior of rare earth tantalates (YbTaO 4 and LuTaO 4 ) are investigated here. Both samples with the m ' phase are successfully fabricated. The formation of oxygen vacancies benefits from atomic substitution and valence variation and the widths of the domain boundaries (18–23 nm) are close to the phonon mean free path . Low thermal conductivity is caused by Umklapp phonon-phonon scattering, oxygen vacancies and domain walls, with LuTaO 4 having a value of 1.903 W m −1 K −1 at 900 °C. Furthermore, LuTaO 4 has decreased oxygen-ion conductivity due to a high activation energy and immobile vacancies. A LuTaO 4 /Si coating can efficiently prevent the oxidation of C/C composites at 1100 °C for 15 h. The coating failure results from oxygen penetrating along the microscopic cracks and mismatch of the thermal expansion coefficients .
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2022
·
IF 4.865
Zhuo Chen,Xiufang Cui,Yongchao Fang,Chao Yan,Rui Wang,Yongzhi Jing,Xinhe Wang,Guo Jin,Xiang Wang
Gd 2 O 3 and Sm 2 O 3 co-doped LZ ceramic ((La 0.5 Gd 0.25 Sm 0.25 ) 2 Zr 2 O 7 /YSZ) are designed and prepared by atmospheric plasma spraying (APS). It is the aim of this study to investigate the similarities and differences between co-doped sample and mono-doped samples, (La 0.5 Gd 0.5 ) 2 Zr 2 O 7 /YSZ and (La 0.5 Sm 0.5 ) 2 Zr 2 O 7 /YSZ on hot corrosion behaviors exposed to Na 2 SO 4 + V 2 O 5 molten salts . Thermodynamic calculations are used to predict the hot corrosion mechanism before experiments. Characterization and hot corrosion behavior are analyzed using X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM). Results indicate that the main hot corrosion products are composed of rare-earth vanadates ((La, Gd)VO 4 , (La, Sm)VO 4 and (La, Gd, Sm)VO 4 , respectively) and ZrO 2 . After 10 h of corrosion, the reaction layer evolves into trilayered structure containing Zr-rich layer, V-rich layer and mixed-layer. The formation mechanism is discussed in detail. The co-doped sample exhibits excellent degradation resistance, which can be attributed to the higher entropy value. The formation of the particular trilayered structure occurs earlier in the co-doped sample, which also provides a role in reducing the degradation rate of ceramics.
研究领域:
材料科学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2020
·
IF 3.784
Yongchao Fang,Xiufang Cui,Guo Jin,Erbao Liu,Dan Zhang,Xin Wen,Qingbo Mi
In this work, hot corrosion behavior of air plasma sprayed La 0.8 Ba 0.2 TiO 3-δ (LBT)-YSZ double-ceramic-layer thermal barrier coating exposed to Na 2 SO 4 + V 2 O 5 molten salt at 900 °C for 20 h was investigated. The phase characterization and microstructural evolution analysis of the coating was carried out after the hot corrosion test by using X-ray diffraction (XRD), scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). The results showed that the LBT-YSZ coating possessed excellent hot corrosion resistance compared with the conventional pure YSZ coating. The conventional pure YSZ coating was completely destroyed after the 10 h test due to the volume change resulting from the adverse phase transition. However, the situation for the LBT-YSZ coatings is completely opposite. The LBT-YSZ coating could prevent the YSZ interlayer underlying the LBT overlayer from densification for at least 20 h. In the LBT overlayer, the double-reaction-layer composed of under dense layer and upper porous layer was formed. In particular, the continuous dense layers with a thickness of ~100 μm formed after 10 h, effectively arresting further penetration of the molten salt. In addition, affected by the diffusion extent of SO 3 gas, the corrosion products of porous layer were composed of Ba 2 V 2 O 7 , LaVO 4 , TiO 2 and BaSO 4 , while those of dense layer consisted of Ba 2 V 2 O 7 , LaVO 4 and TiO 2 . The specific mechanism by which the corrosion reaction occurred was proposed based on Lewis acid-base rule and thermodynamics.
研究领域:
材料科学
·
表面工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Lizhen Li,Junbin Sun,Weihong Lu,Zhifeng Xu
Six multi-component rare earth phosphate materials were prepared by chemical co-precipitation, which are (La 0.2 Nd 0.2 Sm 0.2 Eu 0.2 Gd 0.2 )PO 4 , (La 0 · 2 Ce 0.2 Nd 0.2 Sm 0.2 Eu 0.2 )PO 4 , (Ce 0.2 Nd 0.2 Sm 0.2 Eu 0.2 Gd 0.2 )PO 4 , (La 0.5 Nd 0.5 )PO 4 , (La 0.5 Gd 0.5 )PO 4 and (Nd 0.5 Gd 0.5 )PO 4 . Hot corrosion behavior tests were conducted in molten V 2 O 5 salt at 900 °C and 1000 °C for 20 h and 40 h, respectively. The results show that the corrosion temperature and the heat treatment time have little effect on the type of corrosion products . Among these materials prepared in this study, the material containing Gd element and the material without Gd element exhibit different hot corrosion behavior . For the multi-component rare earth phosphate materials containing Gd element, the corrosion product is ReVO 4 (Re Sm, Eu, Gd) xenotime, and a reaction layer is formed on the surface of the bulk. For the multi-component rare earth phosphate materials without Gd element, the corrosion product is Re(P,V)O 4 (Re La, Ce, Nd) solid solution and the amount of product is very small, the corrosion reaction is extremely weak and no reaction layer is formed. Although the molten salt mainly penetrates, the original structure of the bulk has not been damaged, which indicates that its hot corrosion resistance is good. The hot corrosion mechanisms of these six multi-component rare earth phosphates are studied based on the crystallographic characteristics of rare earth phosphates/vanadates.
研究领域:
材料科学
·
腐蚀科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2023
·
IF 5.7
Shuai Zhang,Shiliang Luan,Ke Ren,Baosheng Xu,Yiguang Wang
Hot-corrosion behavior of Ba 1/3 Sr 1/3 Ca 1/3 Al 2 Si 2 O 8 (BSCAS) in the presence of molten calcium-magnesium-aluminum-silicate (CMAS) is investigated in the temperature range of 1250–1350 °C. In comparison, the hot corrosion behavior of Ba 0.5 Sr 0.5 Al 2 Si 2 O 8 (BSAS) is also studied under the same conditions. The results indicate that CMAS corrosion of both BSCAS and BSAS is caused by the interdiffusion of Ba/Sr and Ca between CMAS and corroded samples. The presence of Ca cations in BSCAS lowers the diffusion driving force of Ca cations between CMAS and BSCAS, resulting in a reduced diffusion rate of Ca cations from CMAS into BSCAS. Moreover, the sluggish diffusion effect of multi-component cations hinders the outward diffusion of Ba/Sr cations from BSCAS. Thus, the BSCAS shows a better CMAS corrosion resistance than BSAS.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
CORROSION SCIENCE
·
2020
·
IF 6.479
Lian-Kui Wu,Jing-Jia Wu,Wei-Yao Wu,Hao-Jie Yan,Mei-Yan Jiang,Fa-He Cao
To improve the hot corrosion resistance, thickness controllable SiO 2 coating was electrodeposited on TiAl alloy. The hot corrosion behavior of the specimens contaminated with 75 wt.% Na 2 SO 4 + 25 wt.% NaCl salt mixture was investigated at 700 °C. Results showed that the generation of compact amorphous SiO 2 embedded with Na 2 Si 4 O 9 and cristobalite was responsible for the enhanced hot corrosion resistance. Moreover, the SiO 2 coating does not only act as a diffusion barrier to sulfur and chlorine but also decreases the oxygen partial pressure at the coating/alloy interface, therefore promoting the selective oxidation of Al to form protective Al 2 O 3 layer.
研究领域:
材料科学
·
腐蚀工程
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2025
·Vol. 46
·期 6
·118062
·
IF 6.2
Shaobo Yang,Chun Guo,Yuan Wang,Jiali Li,Yujie Chen,Sijie Kou,Juanli Deng,Bo Chen,Shangwu Fan
A glass-ceramic derived from a high-yttrium aluminosilicate (HYAS) composition was developed for joining silicon carbide fiber-reinforced silicon carbide (SiC f /SiC) composites. The as-prepared powder exhibited a high softening point (∼1396 °C), good wettability, and a thermal expansion coefficient (3.79 × 10 −6 /K) well matched to that of SiC f /SiC. Dense joints were fabricated at 1420 °C for 60 min, achieving an average lap shear strength of ∼54 ± 2 MPa. The joining mechanism involved crystallization-assisted sintering, liquid-phase densification, and atomic-scale interdiffusion without interfacial reaction layer formation. Hydrothermal corrosion was evaluated in water containing ∼8 ppm dissolved oxygen, approximately three orders of magnitude higher than typical pressurized water reactor (PWR) conditions, to simulate long-term degradation. After 15 days, the joints retained a lap hear strength of ∼37 ± 2 MPa, with corrosion confined to the residual glass phase while interfacial integrity remained intact, demonstrating the promising durability of HYAS glass-ceramic as a durable sealant for SiC f /SiC composites under accelerated hydrothermal conditions.
研究领域:
材料科学
·
陶瓷与复合材料
·
连接技术
·
腐蚀科学
·
核材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）