MATERIALS SCIENCE FORUM
·
2016
·
IF 0
Yu Mei Zhou,Feng Lin Zhang,Peng Cheng Li,Kun Bai,Shang Hua Wu
AlMgB14 is a very hard and brittle material which need be modified for utilizing as cutting tool materials. In present study, TiB2 and Ni3Al were used to strengthen and toughen AlMgB14 material. The microstructure of the AlMgB14-TiB2-Ni3Al composites was analysized by scanning electron microscope (SEM) with energy dispersive X-ray spectroscopy (EDX) and an X-ray diffractometer (XRD). The hardness and fracture toughness of the AlMgB14-TiB2Ni3Al composites were also examined. The results showed that the major phases in AlMgB14-Ni3Al composites were TiB2, AlMgB14, MgAl2O4 , Ni3Al and NiAl. With the increasing of the amount of Ni3Al, more intergranular fractured features can be found in the fractured surface of the composites, the hardness and fracture toughness of the composites were both decreased comparing to the synthesised AlMgB14. The AlMgB14-TiB2-4wt.% Ni3Al composite has a hardness of 28.1 Gpa and a fracture toughness of 3.14 MPa·m1/2.
研究领域:
材料科学
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机械工程
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DOI
International Journal of Applied Ceramic Technology
·
2022
·Vol. 19
·期 4
·1916-1928
·
IF 2.328
Xiao-Chun Deng,Kai-Fei Wang,Guo-Hua Zhang
Combining spray drying and in situ synthesized technology, WC–10Co cemented carbide with uniform composition was prepared by vacuum sintering. The effects of Al 2 O 3 and additions of different rare-earth oxides (La 2 O 3 , Y 2 O 3 and CeO 2 ) on the microstructure and mechanical properties of WC–10Co were investigated. As the Al 2 O 3 content increased from .5 to 2 wt%, the hardness of the sintered sample increased, whereas the relative density and fracture toughness decreased. Compared with the addition of .5 wt% Al 2 O 3 , the WC–10Co alloy with .5 wt% rare-earth oxides had higher hardness. In addition, compared with the alloy without an inhibitor (.80 μm), after adding .5 wt% Al 2 O 3 , La 2 O 3 , Y 2 O 3 and CeO 2 , the WC grain sizes were reduced to .73, .65, .71 and .62 μm, respectively, which indicated that the addition of Al 2 O 3 and rare-earth oxides could refine WC grain during sintering. Among these additives, CeO 2 had the best effect. With the addition of .5 wt% CeO 2 , the hardness and the fracture toughness increased from 1299 to 1710 HV 30 and from 16.18 to 18.90 MPa m 1/2 , respectively.
研究领域:
材料科学
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机械工程
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2023
·
IF 8.7
Lei Liang,Xianxian Sun,Yuanhao Ning,Shasha Wang,Weilong Yin,Yibin Li
The process of toughening brittle ceramics is challenging but important for broadening their range of applications. Extensive studies on toughening brittle alumina (Al 2 O 3 ) ceramics at room temperature have been conducted; however, significantly increasing their toughness at high temperatures remains a challenge. Here, we propose the use of two-dimensional Ti 3 C 2 T x MXene ceramics with high thermal stability to effectively toughen Al 2 O 3 ceramics at high temperatures via a nacre-like structure strategy. The fracture toughness (K Jc ) of the as-prepared MXene/Al 2 O 3 nanocomposite at 1000 °C is 6.02 MPa m 1/2 , 2.4 times that of pure Al 2 O 3 (2.51 MPa m 1/2 ). Moreover, it maintains relatively high strength at 1000 °C (∼193 MPa). The toughening mechanisms - crack deflection, bifurcation and bridging effects - are obtained via in situ observation of crack propagation and finite element simulation. Our novel strategy provides a universal solution to improve the toughness of brittle ceramics at high temperatures and in some special environments.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Qing Wang,Ziyang Ruan,Jianyu Li,Zifan Zhao
Yttrium aluminum garnet (Y 3 Al 5 O 12 , YAG) is regarded as a candidate of thermal barrier coating material for its excellent thermal stability and corrosion resistance, yet the poor fracture toughness and the low thermal expansion coefficient are the roadblock that limits its application. In order to improve the fracture toughness and the thermal expansion coefficients, a series of Y 3 Al 5 O 12 composite ceramics toughened by ferroelastic LaAlO 3 second phase were prepared by in-situ synthesis method in this work. The prepared x LaAlO 3 /(1- x )Y 3 Al 5 O 12 composite ceramics ( x =10∼50%) exhibit superior fracture toughness (2.16 MPa·m 0.5 ∼2.63 MPa·m 0.5 ) with respect to single-phase Y 3 Al 5 O 12 (1.94 MPa·m 0.5 ), which is mainly attributed to the synergistic effects of ferroelastic toughening of second phase, residual stress toughening, and fine-grain strengthening. On the account of the synergistic effects of three toughening mechanisms, 0.2LaAlO 3 /0.8Y 3 Al 5 O 12 composite ceramic manifest the strongest fracture toughness (2.63 MPa·m 0.5 ), which is 36% improved compared with single-phase Y 3 Al 5 O 12 . In addition, the thermal expansion coefficients of x LaAlO 3 /(1- x )Y 3 Al 5 O 12 specimens (9.54∼9.97 × 10 -6 K -1 at 1200 °C) are larger than that of Y 3 Al 5 O 12 (9.25 × 10 -6 K -1 at 1200 °C). Especially, 0.5LaAlO 3 /0.5Y 3 Al 5 O 12 specimen exhibits the highest thermal expansion coefficient (9.97×10 -6 K -1 at 1200 °C), which improve by 7.78% compared to single-phase Y 3 Al 5 O 12 . The improved fracture toughness and the capable thermal expansion coefficients of LaAlO 3 /Y 3 Al 5 O 12 composite ceramics renders their promising aspect for thermal barrier coating application.
研究领域:
材料科学
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陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Chenglu Lian,Zhihua Long,Wei Qian,Zhichen Guan,Kun Huo,Yinqun Hua,Jie Cai
Thermal barrier coating materials play a crucial role ensuring the efficient and stable operation of gas turbines. The thermophysical and mechanical properties of GZ 1-x -GT x (x = 0, 0.1, 0.3, 0.5) composite ceramics, as well as the corrosion resistance properties against calcium magnesium aluminum silicate (CMAS) at 1250 °C, were investigated. The results indicated that the overall properties of Gd 2 Zr 2 O 7 -GdTaO 4 composite ceramics significantly improved with an increase in the second phase GdTaO 4 content. Among all the ceramics designed, GZ 0.5 -GT 0.5 exhibited the lowest thermal conductivity (0.920 W m −1 K −1 at 800 °C) and the highest fracture toughness (2.02 MPa m 1/2 ). Additionally, the molten CMAS interacted with the Gd 2 Zr 2 O 7 -GdTaO 4 composite ceramics, forming a dense apatite layer, which positively contributed to inhibiting CMAS infiltration. Considering its excellent thermal, mechanical, and corrosion resistance properties, Gd 2 Zr 2 O 7 -GdTaO 4 composite ceramics are considered a promising material for thermal barrier coatings.
研究领域:
材料科学
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能源工程
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
·
2024
·
IF 6.1
Qianglong He,Wenchao Guo,Yunwei Shi,Aiyang Wang,Weimin Wang,Zhengyi Fu
In this study, B 4 C–TiB 2 –graphite ceramic composites were prepared via reactive hot-pressing sintering using B 4 C and TiC as the raw materials. The reaction process, microstructure, and mechanical properties were investigated. The solid-phase reaction is a diffusion-controlled process, wherein the B atoms diffuse into TiC and react to form TiB. Thereafter, TiB 2 is generated with the entry of subsequent B atoms. A core–shell structure is formed, wherein TiB 2 particles are wrapped by layered graphite. The products TiB 2 and graphite inhibit the growth of B 4 C matrix grains, which are instrumental in fine grain strengthening. In addition, the novel TiB 2 –graphite-agglomerated structure significantly improves the fracture toughness of the ceramic composites through crack deflection, bridging, and branching toughening mechanisms. Therefore, the comprehensive properties of B 4 C–TiB 2 –graphite ceramic composites are better than those of pure B 4 C ceramics. Specifically, the fracture toughness is approximately 6.77 MPa m 1/2 , which is considerably higher than that of pure B 4 C ceramics (2.47 MPa m 1/2 ).
研究领域:
材料科学
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陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2024
·
IF 8.1
Yang Zhao,Menglin Zhao,Siyuan Wang,Anyang Wang,Zhengping Chang,Zhongqi Wang
With the extensive research on ester-exchanged vitrimer, laminates utilizing vitrimer as matrix have garnered increasing attention due to their healability for achieving long-term durability of the composite structure. However, current research on the healing of mode II delamination for vitrimeric CFRP (vCFRP) laminates remains notably limited. In this study, the ENF tests were implemented to acquire load–displacement curves of eight typical vCFRP laminates with various interfaces. The results indicated a pronounced impact of the stacking interface on the fracture toughness values, the R -curves, fiber bridging effect, and crack growth behaviours . The continuous 0 ° fiber hindered the upward migration for the laminates with 0 ° / / θ ° interface, while the discontinuous θ 1 ° fabric had a lower in-plane strength and were more prone to cracking for the laminates with θ 1 ° / / θ 2 ° interface. Subsequently, the healing efficiencies of specimens were characterized. The healed laminates undergone three shear delamination damages could still achieve a substantial recovery of about 76.33 %.
研究领域:
材料科学
·
复合材料工程
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Communications
·
2024
·
IF 3.7
Gaoxi Cui,Tongyang Li,Ziyue Wang,Lujie Wang,Yuan Yu,Huaguo Tang,Zhuhui Qiao
Soft metal as the second phase to enhance the mechanical and tribological properties of Si 3 N 4 ceramics was a focus of current research. Limited by the doping method and the low melting point of the metal, there were often phenomena such as nonuniform distribution and melting overflow of the second phase, which seriously deteriorated the properties of Si 3 N 4 . In this study, Cu-containing Si 3 N 4 was prepared by in-situ method using copper citrate as the second phase additive. The highly dispersed second phase helped Si 3 N 4 achieve significant improvements in fracture toughness and tribological properties. The phase composition, microstructure, hardness, fracture toughness, and tribological properties of Cu-containing Si 3 N 4 were investigated. XRD results indicated that the reinforcement phase was in the form of Cu 3 Si. When the Cu 3 Si phase content was 3 wt%, the fracture toughness of Cu-containing Si 3 N 4 could be increased by 27.1 % compared to the Si 3 N 4 . When the Cu 3 Si phase content reached 12 wt%, the wear rate at room temperature was reduced by 59 % compared to the substrate. The toughing mechanism could be summarized as the crack bridging and deflection of the Cu 3 Si phase. The anti-wear mechanism could be concluded as the reduction of micro-cracks in the friction film with the participation of Cu 3 Si phase, thus reducing the loss in the friction process.
研究领域:
材料科学
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机械工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
·
2025
·
IF 4.6
Fengshun Du,Bohua Duan,Dezhi Wang,Zhuangzhi Wu,Xinli Liu
Improving the poor plasticity and fracture toughness of molybdenum alloys is the key to expanding their industrial applications. In this experiment, a cerium partially stabilized zirconia (Ce-PSZ) reinforced molybdenum alloy with outstanding properties was obtained by combining the hydrothermal method and the powder metallurgy technology. This study investigated how varying Ce-PSZ content influences the microstructure and mechanical properties of Mo/Ce-PSZ alloys. The results show that with increasing Ce-PSZ addition, the relative density and hardness of the alloys gradually increase, while the tensile strength, plasticity, and fracture toughness exhibit a tendency to initially increase and subsequently decrease. When 1.5 wt% of Ce-PSZ is added, the Mo alloys achieve excellent overall mechanical properties, with an ultimate tensile strength of 528.5 MPa, elongation of 29.3 %, and fracture toughness of 38.5 MPa∙m 1/2 . These values are about 22.7 %, 22.5 %, and 83.3 % higher than those of pure molybdenum. The substantial enhancement in elongation and fracture toughness can be predominantly ascribed to the refinement of grains and the stress-induced Ce-PSZ phase transformation. This research provides a novel method for the preparation of molybdenum alloys with high fracture toughness and elongation.
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 Research Express
·
2019
·Vol. 6
·期 5
·056547
·
IF 1.449
Yinqun Hua,Bochen Jiang,Ruifang Chen,Jiangdong Cao,Wenwen Shuai,Ruitao Li
In this study, Gd2Zr2O7 -X TiSi2 (X = 0, 2.5, 5 and 7.5 wt% TiSi2) ceramics were synthesized by solid state reaction method at 1550 °C for 12 h in air. The influences of TiSi2 content on the phase, microstructure, thermophysical properties, hardness and fracture toughness were investigated. Gd2Zr2O7- X TiSi2 (X = 7.5 wt%) ceramic mainly consists of a defect fluorite phase; while Gd2Zr2O7 -X TiSi2 (X = 0, 2.5 and 5 wt% TiSi2) ceramics have an ordered pyrochlore phase. In addition, the degree of structural order decreased with the increasing TiSi2 content. The microstructure of the doped ceramic materials exhibited grain refinement. The doping of TiSi2 decreased the thermal conductivity while improved the thermal expansion coefficient, the hardness and the fracture toughness enhanced significantly. With these improved properties, the TiSi2 doped Gd2Zr2O7 ceramic materials can be a very promising material for ceramic layers of thermal barrier coating.
研究领域:
材料科学
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热障涂层研究
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 14
·7645-7651
·
IF 3.049
Xin Wang,Min Xue,Songbai Liu,Kuo Jiang,Zhuli Zhang
Herein, powders composed of La2Zr2O7 (LZ) and ZrO2 phases were synthesized by an in situ reaction using a sol-spray pyrolysis method; moreover, 24 mol% LaO1.5–ZrO2 (volume ratio = 1 : 1) powders were characterized by XRD, Raman spectroscopy, SEM, and TEM. XRD and Raman results showed that the samples maintained a tetragonal ZrO2 and a pyrochlore LZ phase from 900 to 1100 °C. The addition of LZ could be helpful in the stabilization of t-ZrO2 and decreasing the grain size of ZrO2. The SEM results revealed that the LZ and ZrO2 phases were homogeneously distributed in the sintered bulk. The HRTEM results suggested that the crystal orientations of the nano-LZ and nano-ZrO2 phases were accordant; this was in agreement with the characteristics of the coherent boundaries. The fracture toughness of LZ–ZrO2 was markedly improved by the transformation toughening of the ZrO2 phase, and a value that was 2.2-fold that of the LZ prepared by a similar technique was achieved.
研究领域:
材料科学
·
陶瓷学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 53
·42362-42368
·
IF 3.84
Zhengguang Heng,Yang Chen,Huawei Zou,Mei Liang
A PEG-b-CTBN diblock copolymer was synthesized via the esterification reaction of hydroxy terminated methoxypolyethylene glycols (PEG) in the presence of a carboxyl-terminated butadiene-co-acrylonitrile copolymer (CTBN) with 4-dimethylaminopyridine (DMAP) as the catalyst. Epoxy thermosets were modified via the formation of a nanostructure. The result of transmission electronic microscopy (TEM) shows spherical domains were homogeneously dispersed into the continuous epoxy matrix and the size is nano-scale. It was noted that the glass transition temperatures decreased with an increase in the content of PEG-b-CTBN, which was evidenced by Dynamic Mechanical Analysis (DMA) and a Differential Scanning Calorimeter (DSC). Through mechanical tests, we found the tensile strength and fracture toughness of epoxy resins were simultaneously enhanced by nanostructured PEG-b-CTBN.
研究领域:
材料科学
·
高分子化学
✓ 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）