METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
·
2018
·Vol. 49
·期 8
·3683-3691
·
IF 1.887
Cai Xiaoping,Liu Yanan,Wang Xiaohong,Jiao Xinyang,Wang Jianzhong,Akhtar Farid,Feng Peizhong
Open-cell Fe-Al intermetallic foams were successfully prepared by a simple and energy-saving thermal explosion (TE) process. The effects of the Fe/Al molar ratio (Fe-(40–50) at. pct Al) and thermal treatment temperature on the TE temperature profile, phase composition, pore characteristics, and oxidation resistance of the prepared foams were investigated. The results showed that the Al content significantly influenced the ignition ( T ig ) and combustion ( T c ) temperatures of the TE process; in particular, as the Al content decreased, T ig increased gradually from 623 °C to 636 °C and T c decreased from 1059 °C to 981 °C. FeAl was identified as the dominant phase in the thermally treated foams. The Fe-Al intermetallic foams displayed an open porosity of 60 vol pct, with pores connected with each other to form an open pore structure. The formation of the pores was attributed to the expansion of interparticle pores in the pressed body during the TE reaction. X-ray photoelectron spectroscopy analysis of the Fe-50Al foam showed that the Al 2p and O 1s binding energies were 74.5 eV and at 531.4 eV, respectively. The formation of a surface alumina layer in the early stages of the oxidation process resulted in the parabolic oxidation rate law, and the Fe-50Al foams exhibited an excellent resistance to oxidation at 650 °C in air. These results suggest that the synthesized Fe-Al foams represent promising materials for applications involving an oxidizing environment and high temperatures.
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
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Yang Yu,Xiaoping Cai,Xinyang Jiao,Chengyi Xu,Jinan Niu,Peizhong Feng
Ni-Al-Cr intermetallic compounds are candidate at extreme environment due to their excellent oxidation resistance at high temperature, and the oxidation resistance of Ni-Al-Cr alloy system has been studied extensively. However, the research on oxidation resistance mechanism of porous Ni-Al-Cr intermetallic compounds is still not deep. In our work, porous Ni-Al-Cr intermetallic compounds were synthesized by thermal explosion, and the oxidation resistance of porous Ni-Al-Cr system was mainly investigated. The results indicate that Cr promotes the formation of highly protective continuous Al 2 O 3 layer, increasing the oxidation resistance at 900 °C of porous Ni-Al-Cr. After oxidation at 900 °C for 120 h, the minimum mass gain of Ni-Al-Cr products is only 6.96%.
研究领域:
材料科学
·
高温材料
·
腐蚀与防护
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS CHARACTERIZATION
·
2022
·
IF 4.537
Yang Yu,Xiaoping Cai,Zhejian Cao,Xinyang Jiao,Weining Xie,Yong Yu,Peizhong Feng
Porous NiAl intermetallic compounds demonstrate great potential in various applications by their high porosity and excellent oxidation resistance . However, to obtain a controllable NiAl intermetallic structure by tuning different process parameters remains unclear. In this work, porous NiAl intermetallic compounds were fabricated by economic and energy-saving thermal explosion (TE) reaction. The relationship between microstructure and process parameters was revealed using three-dimensional X-ray microscopy (3D-XRM) with high resolution and non-destructive characteristics. The geometrical features and quantitative statistics of the porous NiAl obtained at different heating rates (2, 10, 20 °C min −1 ) were compared. The result of the closed porosity calculation showed that a lower heating rate (2 °C min −1 ) promoted the Kirkendall reaction between Ni and Al, resulting in a high closed porosity (5.25%). However, at a higher heating rate (20 °C min −1 ), a homogeneous NiAl phase was observed using the threshold segmentation method, indicating uniform and complete TE reaction can be achieved at a high heating rate. The result of the 3D fluid simulation showed that the sample heated at 10 °C min −1 had the highest permeability (2434.6 md). In this study, we systematically investigated the relationship between the heating rates and properties of the porous NiAl intermetallic, including the phase composition, porosity, exothermic mechanism, oxidation resistance, and compression resistance. Our work provides constructive directions for designing and tailoring the performance of porous NiAl intermetallic compounds.
研究领域:
材料科学
·
冶金工程
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS CHARACTERIZATION
·
2023
·
IF 4.7
Chengyi Xu,Xiaoping Cai,Xinyang Jiao,Khanh Ly Vu,Zhichao Shang,Peizhong Feng
Porous CoAl 3 intermetallics have great catalytic potential. However, its high porosity and controllable preparation are still incipient. In this paper, the effect of isothermal treatment on the near-net formation process of porous CoAl 3 material is studied, and the phase transformation process and diffusion kinetics of the Co/Al diffusion couple in the solid-phase diffusion stage are described. The results show that isothermal treatments in the range of 510–550 °C reduce the exothermic intensity of the thermal explosion (TE) reaction. The holding time of 30 min at 530 °C facilitates the near-net formation of porous CoAl 3 . The isothermal treatment does not affect the phase composition of the final product. Still, it causes changes in the phase and depth of the diffusion, affecting the exothermic strength and skeleton morphology. Based on the phase transition and thermodynamic analysis , the CoAl phase formation is the key to reducing the exothermic intensity. The diffusion kinetics indicates that the low diffusion activation energy of the CoAl phase (Q 1 = 1.66 kJ mol −1 ) is the main reason for the preferential formation. And the exponential kinetic factor of the second diffusion layer (n 2 = 0.75) explains its high diffusion depth.
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
Progress in Natural Science-Materials International
·
2019
·
IF 3.31
Xinyang Jiao,Xiaoping Cai,Gao Niu,Xuanru Ren,Xueqin Kang,Peizhong Feng
Porous TiAl 3 intermetallics were synthesized from Ti-75 at.% Al elemental powder mixtures using an energy-saving and rapid reactive method of thermal explosion (TE). The results demonstrated that the actual temperature of the compact climbed rapidly from 673 °C to 1036 °C within 24 s, indicating that an obvious TE reaction occurred during sintering process. The video graphs suggested that the TE in Ti–Al system behaved instant occurrence and overall heating whether from axial or radial direction. The silver wires and NaCl particles that pressed on the surface of the sample disappeared due to the heavy heat released during TE reaction. Only pure TiAl 3 phases were synthesized in TE products and the open porosity of 55.4% was easy to obtain. After high-temperature treatment at 1000 °C, large amounts of sintering-neck formed and then improved the compressive strength of porous TiAl 3 materials. Moreover, the mass gain curve of porous TiAl 3 intermetallics oxidized at 650 °C for 120 h exhibited the parabolic oxidation rate law. XPS analysis confirmed that the strong O 1s peak was 531.4 eV which was the typical binding energy of Al 2 O 3 . Therefore, the excellent oxidation resistance of porous TiAl 3 foams would be considered as good candidate materials for prolonging the service life at high temperatures.
研究领域:
材料科学
·
高温材料
✓ 已验证
产品关联
DOI
高影响因子
INTERMETALLICS
·
2022
·
IF 4.075
Chengyi Xu,Xiaoping Cai,Xinyang Jiao,Yang Yu,Xiaohong Wang,Jianzhong Wang,Lu Zhu,Peizhong Feng
Porous CoAl 3 is a candidate material in the field of catalytic due to its high porosity, good thermostability and quasicrystal structure. However, its rapid preparation are still a challenge, and the oxidation resistance need to be further investigated. In this work, we have rapidly prepared porous CoAl 3 by thermal explosion (TE) reaction and studied its oxidation process . The results show that two exothermic peaks at 616 °C and 646 °C, corresponding to the solid-phase diffusion and TE reaction, respectively. The heat released from the two reactions led to the expansion of the compact, which reached a maximum of 104% at 800 °C, and the corresponding open porosity reached at 53%. The pore sources include the original pores during the green compact pressing process, the Kirkendall pores generated by the solid-phase diffusion process and the in-situ pores generated by the Al consumption after the TE occurs. The cyclic oxidation of porous CoAl 3 at 700 °C for 130 h only increased the weight by 1.52%, forming a continuous protective oxide film on the surface of the skeleton. It has been found that porous CoAl 3 can combine the oxidation resistance of Co–Al monoliths alloys and the high porosity of porous materials, which have potential applications in the field of catalysis such as methanation at 600–700 °C.
研究领域:
材料科学
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2018
·
IF 3.057
Guanghua Liu,Zengchao Yang,Jiangtao Li,Gang He,Yixiang Chen,Kexin Chen,Dingdong Fan
Ti 1−x W x C solid solution powders have been prepared by combustion synthesis in two reaction modes of self-propagating high-temperature synthesis (SHS) and thermal explosion (TE). The reaction mechanism in combustion synthesis is investigated and the effects of processing parameters are discussed. Two reaction paths are proposed for the formation of the Ti 1−x W x C solid solution. In path 1, Ti 1−x W x C crystals are directly precipitated from Ti-W-C melt, and in path 2 the Ti 1−x W x C phase is formed by solid-state reaction between TiC and WC. The availability of the two reaction paths depends on the x value and reaction temperature. For smaller x values and higher temperatures, the reaction path 1 dominates and almost full conversion is achieved. For larger x values and lower temperatures, however, path 2 becomes dominant. In path 2, the rate-limiting step is the formation of WC by slow diffusion-controlled solid-state reaction between W and C, which is unable to be completed during the short reaction period and results in the presence of W 2 C and unreacted W in the products. The reaction between W and C cannot be improved by the addition of excessive C, but can be promoted by using carbon black instead of graphite powder as C source or carrying out the synthesis in a high-pressure N 2 atmosphere instead of vacuum. In the fast combustion reaction with high heating/cooling rates, a non-equilibrium state is likely to be created because the mass transfer and energy exchange are limited. The non-equilibrium condition has a strong influence on the reaction kinetics, where the decomposition of W 2 C is avoided, a localized compositional heterogeneity is caused, and ultrafine grains on a submicron scale are obtained in the products.
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
CORROSION SCIENCE
·
2022
·
IF 7.72
Zhichao Shang,Xiaoping Cai,Xinyang Jiao,Yan Zheng,Baojing Zhang,Farshid Pahlevani,Peizhong Feng
With the increasing demand for high-temperature gas filtration, porous intermetallic compounds have attracted much attention. In this study, high porosity CoAl with 3D microstructures was prepared using the thermal explosion. The link between the pore structure , mechanical and oxidation resistance of the product was established using 3D-XRM. Moreover, an oxidation corrosion test was conducted in fluid and static air at 700–900 °C for up to 120 h. During the rapid growth stage, the mass gain was dominated by the inward diffusion of O, while during the slow growth stage, it was dominated by the outward diffusion of Al.
研究领域:
材料科学
·
高温材料
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Zhichao Shang,Man Zhang,Jingjing Qu,Sanjith Udayakumar,Xintan Bai,Xiaohong Wang,Baojing Zhang,Jianzhong Wang,Farshid Pahlevani,Peizhong Feng
Chemical/electrochemical dealloying was applied to porous CoAl intermetallic (IMC) precursors synthesized via a rapid thermal explosion (TE) method, producing Co 3 O 4 (O V ) self-supported materials with rod-like, nano-flower, and honeycomb-like nanostructures. The investigation thoroughly explored the phase composition, exothermic behavior, precursor morphology, electrochemical characteristics of the dealloyed products, and the mechanism of oxygen vacancies that influence the performance of supercapacitors. The diffusion of intermediate phases governs the exothermic behavior and structural integrity of the CoAl IMC precursors, formatting a precursor with a porous material featuring a 3D microstructure. The effect of dealloying time, temperature and, applied potential on the nanostructure of the sample was examined, ultimately enabling the controlled synthesis of nano-flower Co 3 O 4 (O V ) in the dealloying process. The synthesized self-supported Co 3 O 4 (O V ) materials with a relatively high concentration of oxygen vacancies and a high specific surface area (36.69 m²/g). The materials showed high capacitance (11.25 F/cm 2 at 10 mA/cm 2 ) and exceptional cyclic stability (the decay rate per cycle is 0.013 % at 20 mA/cm 2 after 2000 cycles). DFT simulations demonstrated that the O V creates additional unsaturated coordination sites, enhancing the storage capacity by facilitating ion insertion and extraction, thus significantly boosting the specific capacity.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
DOI
高影响因子
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
·
2021
·
IF 5.234
Xiaoping Cai,Xuanru Ren,Changcheng Sang,Lu Zhu,Zhoujun Li,Peizhong Feng
To meet the requirements of energy-efficiency and high quality joining in the emerging industries field, a novel thermal explosion (TE) joining method was developed. The dissimilar Ni/316SS joint was first obtained by the TE reaction technology. The Ni-Al mixed powder was selected as TE reaction system, and the reaction product was used as interlayer. The effect of temperature (800, 850 and 900 °C), hold time (5, 10, 15 and 20 min) and joining pressure (0, 10, 20 and 30 MPa) on interfacial microstructure, diffusion behavior and mechanical properties of Ni/316SS joint were investigated. The maximum combustion temperature of Ni-Al interlayer during heating process was 1655 °C and a significant exothermic phenomenon was lasted for 2 s. 316SS(Al), Fe 2 Al 5 (Ni, Cr) and serration-like Ni 5 Al 3 and Ni 3 Al were detected at the interface containing a reaction layer because of element diffusion. The maximum shear strength of the Ni/316SS joint was 65.2 MPa, and the failure is characterized by typical brittleness fracture. The fracture mode is the combination of partial spalling and fracture of the interlayer. The post heat-treatment assisted TE joining technique significantly shortened the bonding process of the dissimilar Ni/316SS joint at moderate temperatures, realizing the low energy and efficient joining between Ni and 316SS.
研究领域:
材料科学
·
焊接工程
✓ 已验证
产品关联
DOI
高影响因子
CORROSION SCIENCE
·
2023
·
IF 8.3
Zhichao Shang,Xiaoping Cai,Hao Wang,Farshid Pahlevani,Yan Zheng,Yang Yu,Baojing Zhang,Peizhong Feng
The micro/nano-scale porous CoAl intermetallic compound (IMC) was fabricated using thermal explosion (TE) method combining space holder. By investigating the samples with 3D-XRM, the link between the structure of the pores and the permeability performance of the product was established. Oxidative corrosion tests were performed in static air at 600 °C for 120 h. There are two stages of corrosion: in the first four hours of the oxidation experiment, the reaction of O was mainly dominated; after that, the diffusion of Al was dominated. This structure-function integrated porous CoAl will create a new pathway for industrial-scale high-temperature oxygenated gas filtration works.
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
危险品化学品经营许可证（带存储）