JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Chenguang Guo,Xingyu Li,Lin Zhang,Yuan Shi,Peng Zhang,Zichen Wei,En Mei,Zhongyou Que,Mingli Qin,Xuanhui Qu
Ultrafine-grained (UFG) VNbMoTaW refractory high entropy alloy (RHEA), reinforced with carbide particles, was prepared through a novel powder metallurgy route. Initially, pre-alloyed RHEA powder, characterized by body-centered cubic (BCC) phase, ∼88 nm particle size and good dispersity, was fabricated via a wet-chemical (WC) method. The high quality of the nano powder enabled low-temperature sintering with suppressed grain growth. Subsequently, a dense UFG VNbMoTaW RHEA bulk sample was fabricated by spark plasma sintering (SPS). It provided uniform microstructure with 99 % theoretical density and ∼320 nm grain size. The residual carbon from powder facilitated the precipitation of carbide phases in the sintering process. These carbide precipitates were identified by a high-entropy characteristic, ∼180 nm particle size and a volume fraction of 8.3 %, serving as effective reinforcing agents for the RHEA matrix. Benefiting from the high configurational entropy, ultrafine grain size, and precipitate phase, the bulk RHEA exhibited excellent mechanical properties in terms of a high hardness of 10.9 GPa and a compressive strength of 4.2 GPa with an acceptable strain of 10.7 %. We expect such a powder metallurgy route should also be applicable to other systems of RHEAs.
研究领域:
材料科学
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冶金工程
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
·
2022
·
IF 4.804
Ben Chen,Zhi-Bo Li,Jun-Ru Liu,Guo-Hua Zhang
Powder metallurgy approach was used to produce fine-grain tungsten heavy alloys (WHAs), and the effect of Mo addition on the microstructures and mechanical properties of the alloy was discussed. The W-Mo-Ni-Fe ultrafine composite powders were prepared via method consisting of steps of carbothermic pre-reduction and subsequent deep hydrogen reduction. The sintered compacts of these W-Mo-Ni-Fe composite powders reached virtually full densification after sintering at 1500 °C for 2 h. It was discovered that the W grain size of WHAs reduced due to the Mo addition (0, 2.5, 5, 10 wt%). Tensile test results showed that the alloy with 5 wt% Mo exhibited the maximum ultimate tensile strength and elongation, which has a significant relationship with finer W grain size, lower W W contiguity and higher volume fraction of the γ-(Ni, Fe) matrix phase. It was also concluded that the major fracture characteristic of WHAs were transformed from W W decohesion to W-matrix interface separation with increasing the addition amount of Mo.
研究领域:
材料科学
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冶金工程
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
·
2024
·
IF 4.2
He Zhang,Guo-Hua Zhang
In this study, using the ultra-fine molybdenum-27.5 wt% copper-(0–5) wt% tungsten-1.75 wt% nickel-0.75 wt% iron-0.5 wt% cerium dioxide composite powders as experimental materials, molybdenum‑copper‑tungsten‑nickel‑iron‑cerium dioxide blocks were obtained through low-temperature powder sintering. All alloy samples owned high relative densities (98.1 ± 0.05–98.9 ± 0.05%). Besides, the formations of molybdenum‑tungsten and γ-(copper, nickel, iron) solid solutions guaranteed the sample owned good comprehensive strength. Sintered block with the highest tension strength, compression strength, bending strength and hardness was prepared through introducing 2.5 wt% tungsten, which were 586 ± 4 MPa, 2928 ± 11 MPa, 1554 ± 5 MPa and 305 ± 3 HV respectively. However, the presences of iron, nickel and cerium dioxide affected the conductivities, and therefore, electric conductivities of the samples were 33.08 ± 0.02–33.47 ± 0.02 %IACS.
研究领域:
材料科学
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冶金工程
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED ENGINEERING MATERIALS
·
2022
·Vol. 24
·期 10
·2200125
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IF 4.122
Xudong Yang,Mingrui Xie,Weiting Li,Junwei Sha,Naiqin Zhao
Silicon (Si) has a significant influence on the cellular structure and microstructure of the aluminum (Al) foams, which in turn will notably affect their mechanical responses. Herein, the Al–Si foams are fabricated via a novel powder metallurgy foaming approaches with multiple Si contents to investigate the role of Si concentrations on the structural and mechanical properties. The results show that the certain contents of Si can not only delay the expansion process, but also increase the maximum expansion rate to improve the cellular structure. Specifically, the AlSi7 foams process the optimal comprehensive compressive properties of yield stress (4.36 MPa), plateau stress (6.02 MPa), and energy absorption capacity (3.47 MJ m −3 ) with the relative density of 0.15. However, excessive Si can decrease the expansion rate and deteriorate the cellular structure. Moreover, the deformation mode of the Al foams during compressive process converts from plastic mode to brittle mode by the adding of Si. Generally, the AlSi7 foams possess an excellent trade-off between toughness and brittleness and exhibit the optimal mechanical responses.
研究领域:
材料科学
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机械工程
✓ 已验证
DOI
高影响因子
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
·
2022
·
IF 6.044
Y. Xing,N.Y. Li,C.J. Li,P. Gao,H.D. Guan,C.M.Y. Yang,C.J. Pu,J.H. Yi
SiC particles (SiC p ) reinforced Al matrix composites as the one of the most representative ones in the field of metal matrix composites , and many researches about the enhancement effect of SiC p size on mechanical properties of SiC p /Al composites have mainly focused on the comparison of micron-sized and nano-sized SiC p . In this paper, low-cost submicron-sized SiC p with rare attention was used as novel reinforcements, and the enhancement effect was compared with that of nano-sized SiC p . At the same time, a strategy of oxidation treatment for SiC p is developed in the field of powder metallurgy , and related work has been carried out. Raw submicron-sized SiC p (hereafter named SiC smp ) and raw nano-sized SiC p (hereafter named SiC np ) were calcined at 1100 °C. Then, SiC smp (raw and oxidized) and SiC np (raw and oxidized) were used as reinforcements to prepare Al matrix composites with different reinforcement content by powder metallurgy. The enhancement effect of raw SiC np is slightly better than that of raw SiC smp when the content is below 7 vol%. Although the agglomerations of oxidized SiC p were found owing to increased agglomeration tendency after oxidation treatment for SiC p , the tensile strength of composites were enhanced significantly, especially for SiC np /Al composites. Furthermore, the ductility of SiC smp /Al composites was also improved after calcining for SiC smp and thus excellent comprehensive mechanical properties were obtained.
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
Nanomaterials
·
2020
·Vol. 10
·期 3
·438
·
IF 4.324
Jianian Hu,Jian Zhang,Guoqiang Luo,Yi Sun,Qiang Shen,Lianmeng Zhang
This research presents an approach for C-O grain boundary strengthening of Al composites that used an in situ method to synthesize a C-O shell on Al powder particles in a vertical tube furnace. The C-O reinforced Al matrix composites (C-O/Al composites) were fabricated by a new powder metallurgy (PM) method associated with the hot pressing technique. The data indicates that Al4C3was distributed within the Al matrix and an O-Al solution was distributed in the grain boundaries in the strengthened structure. The formation mechanism of this structure was explained by a combination of TEM observations and molecular dynamic simulation results. The yield strength and ultimate tensile strength of the C-O/Al composites, modified by 3 wt.% polyvinyl butyral, reached 232.2 MPa and 304.82 MPa, respectively; compared to the yield strength and ultimate tensile strength of the pure aluminum processed under the same conditions, there was an increase of 124% and 99.3%, respectively. These results indicate the excellent properties of the C-O/Al-strengthened structure. In addition, the strengthening mechanism was explained by the Hall–Petch strengthening, dislocation strengthening, and solid solution strengthening mechanisms, which represented contributions of nearly 44.9%, 15.9%, and 16.6% to the total increased strength, respectively. The remaining increment was attributed to the coupled strengthening of the C and O, which contributed 20.6% to the total increase.
研究领域:
材料科学
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力学
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纳米技术
✓ 已验证
DOI
高影响因子
Carbon Letters
·
2024
·Vol. 34
·期 5
·1317-1327
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IF 5.5
Yang Xiaohong,Cheng Xingwang,Chen Yu,Xiao Peng
To reduce production cost and inhibit the aggregation of graphene, graphene oxide and copper nitrate solution were used as raw materials in the paper. Cu particles were introduced to the graphene nanosheets by in-situ chemical reduction method in the hydrazine hydrate and sodium hydroxide solution, and the copper matrix composite reinforced with Cu-doped graphene nanosheets were fabricated by powder metallurgy. The synthesized Cu-doped graphene was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The relative density, hardness, electrical conductivity and tensile strength of the copper matrix composite reinforced with Cu-doped graphene were measured as well. The results show that copper ions and graphene oxide can be effectively reduced by hydrazine hydrate simultaneously. Most of oxygen functional groups on the Cu-doped graphene sheets can be removed dramatically, and Cu-doped graphene inhibit the graphene aggregation effectively. Within the experimental range, the copper matrix composites have good comprehensive properties with 0.5 wt% Cu-doped graphene. The tensile strength and hardness are 221 MPa and 81.6 HV, respectively, corresponding to an increase of 23% and 59% compared to that of pure Cu, and the electrical conductivity reaches up to 93.96% IACS. However, excessive addition of Cu-doped graphene is not beneficial for the improvement on the hardness and electrical conductivity of copper matrix composite.
研究领域:
材料科学
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纳米技术
✓ 已验证
DOI
高影响因子
Materials Science & Engineering C-Materials for Biological Applications
·
2015
·
IF 3.088
Yong Liu,Kaiyang Li,Tao Luo,Min Song,Hong Wu,Jian Xiao,Yanni Tan,Ming Cheng,Bing Chen,Xinrui Niu,Rong Hu,Xiaohui Li,Huiping Tang
In this work, powder metallurgical (PM) Ti–Mg alloys were prepared using combined techniques of mechanical alloying and spark plasma sintering. The alloys mainly consist of super saturations of Mg in Ti matrix, and some laminar structured Ti- and Mg-rich phases. The PM Ti–Mg alloys contain a homogeneous mixtures of nanocrystalline Mg and Ti phases. The novel microstructures result in unconventional mechanical and biological properties. It has been shown that the PM Ti–Mg alloys have a much lower compression modulus (36–50 GPa) compared to other Ti alloys, but still remain a very high compressive strength (1500–1800 MPa). In addition, the PM Ti–Mg alloys show good biocompatibility and bioactivity. Mg can dissolve in the simulated body fluids, and induce the formation of the calcium phosphate layer. The compression modulus of PM Ti–Mg alloys decreases with the amount of Mg, while the bioactivity increases. Although the corrosion resistance of Ti–Mg alloys decreases with the content of Mg, the alloys still show good stability in simulated body fluid under electrochemical conditions. The indirect and direct cytotoxicity results show that PM Ti–Mg alloys have a good biocompatibility to NIH-3T3 cells. Therefore, the PM Ti–Mg alloys are promising candidates in biomedical applications.
研究领域:
材料科学
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生物医学工程
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产品关联
DOI
PubMed
高影响因子
Metals
·
2018
·Vol. 8
·期 10
·738
·
IF 1.704
Qiong Xu,Aibin Ma,Junjie Wang,Jiapeng Sun,Jinghua Jiang,Yuhua Li,Chaoying Ni
Relatively low compactness and unsatisfactory uniformity of reinforced particles severely restrict the performance and widespread industry applications of the powder metallurgy (PM) metal matrix composites (MMCs). Here, we developed a combined processing route of PM and equal channel angular pressing (ECAP) to enhance the mechanical properties and wear resistance of the SiCp/Al-Si composite. The results indicate that ECAP significantly refined the matrix grains, eliminated pores and promoted the uniformity of the reinforcement particles. After 8p-ECAP, the SiCp/Al-Si composite consisted of ultrafine Al matrix grains (600 nm) modified by uniformly-dispersed Si and SiCpparticles, and the composite relative density approached 100%. The hardness and wear resistance of the 8p-ECAP SiCp/Al-Si composite were markedly improved compared to the PM composite. More ECAP passes continued a trend of improvement for the wear resistance and hardness. Moreover, while abrasion and delamination dominated the wear of PM composites, less severe adhesive wear and fatigue mechanisms played more important roles in the wear of PM-ECAP composites. This study demonstrates a new approach to designing wear-resistant Al-MMCs and is readily applicable to other Al-MMCs.Keywords:SiCp/Al-Si composites;powder metallurgy (PM);rotary-die equal-channel angular pressing (RD-ECAP);wear performance
研究领域:
材料科学
·
机械工程
✓ 已验证
产品关联
DOI
高影响因子
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
·
2022
·Vol. 53
·期 3
·1085-1098
·
IF 2.726
Li Zhi-Bo,Zhang He,Zhang Guo-Hua,Chou Kuo-Chih
In order to fabricate high-performance tungsten heavy alloys (97W–2.1Ni–0.9Fe (wt pct) and 99W–0.7Ni–0.3Fe) with higher W content and density by powder metallurgy technique, the ultrafine composite powder was synthesized through two-step reduction approach and used as the raw materials. Contrary to the expectations, it was found that a small amount of Ni has a great effect in activated pre-sintering, resulting in an undesired grain growth of W to micron size. Therefore, another simple and efficient method was developed to prepare high-purity, ultrafine and high-W-content composite powders. The sintering densification behavior of the prepared composite powders, as well as mechanical properties and corrosion resistance of as-sintered alloys were systematically investigated. The bending strength, compression strength, hardness, fracture toughness and anti-corrosion property of obtained 97W–2.1Ni–0.9Fe alloys are better than those of 99W–0.7Ni–0.3Fe alloys, attributed to the more homogeneous microstructure comprised of finer W grain and larger volume fraction of matrix phase.
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
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
·
2020
·
IF 3.407
Y. Jiang,J. Hou,P. Huang,J. Li,E.H. Wu,Z. Xu,Q.S. Liu,Zhuoming Xie,Qianfeng Fang
Hybrid tungsten composites reinforced with zirconium carbide (ZrC) nanoparticles and tungsten fibers were developed by the conventional powder metallurgy process (ball-mill mixing of powders and fibers followed by spark plasma sintering). The synergistic and mutual influences of the fibers and nanoparticles on tungsten were investigated in tensile behavior and fracture-energy tests. Aided by the ZrC nanoparticles, up to 30% of the fibers could be embedded in the tungsten matrix. The fracture energy was maximized by co-introducing 0.2 wt% ZrC particles with 20 wt% short tungsten fibers. The fracture-energy enhancement of the short fibers is contributed by pseudo-toughness from the fiber–matrix interface, inherent toughness from the fibers themselves, and grain refinement (by 50%) of the tungsten matrix. The fracture energy of the composite is very sensitive to the ZrC content, because the two-way action of ZrC weakens the pseudo-toughness of the interface energy.
研究领域:
材料科学
·
力学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Q. Yan,B. Chen,B. Zhang,T. Zhang,J. Wan,J. Shen,H.C. Kou,J.S. Li
The high reaction tendency between graphene and titanium (Ti) matrix during fabrication of graphene/Ti composites aggravates the structural integrity of graphene and limits its outstanding strengthening potential. In order to solve this problem, in this study, few-layered graphene (FLG) decorated with SiC nanoparticles (SiCp@FLG) was synthesized to reinforce Ti-6Al-4V (Ti64) alloy via a powder metallurgy route. Microstructure and Vickers hardness of the developed SiCp@FLG/Ti64 composites were studied systematically. Results showed that the SiCp decoration changed the morphology of FLG/Ti interface from continuous TiC reaction layer to discontinuous TiC nanoparticles during hot-press sintering. This discontinuous interface not only kept the integrity of FLG by suppressing its reaction with Ti matrix but also led to direct bonding between FLG and Ti. This designing strategy of protecting the reinforcement by secondary particle decoration can be potentially applied to the development of high-performance metal matrix composites .
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
危险品化学品经营许可证（带存储）