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学者姓名:贺定勇
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Abstract :
Soil-engaging components of agricultural machinery are susceptible to physical degradation due to the long-term wear from sand, gravel, weeds, and plant stalks. In order to improve their wear resistance and prolong the service life, a hardfacing alloy of hypoeutectic high chromium cast iron containing TiC was made on the Q235 steel substrate via the flux-cored arc welding method. Effects of in-situ precipitation of TiC and direct addition of TiC to the powder core on the wear resistance of hardfacing alloy were studied by the MLS-225 wet rubber wheel wear tester and self-made impeller-roller impact-abrasion testing machine. In addition, after tests, the samples were characterized using optical microscope (OM), Rockwell hardness tester, X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS). The results showed that the hardfacing alloy of hypoeutectic high chromium cast iron mainly consists of gamma-Fe, alpha-Fe, M7C3, and TiC, TiC can act as the heterogeneous nucleation core for precipitates austenite first in the organization, increasing their nucleation rate and preventing their growth during solidification, resulting in the refinement of the austenite organization. The TiC introduced by in-situ synthesis has a smaller size and a more diffusely homogeneous distribution than that introduced by direct addition to the powder core. In addition, TiC increased the content of eutectic carbides in the organization and improved the hardness of the hardfacing alloy. The wear forms of all three hardfacing alloys after the abrasive wear test are dominated by micro-cutting, and the grooves on the wear surface of the hardfacing alloy without added TiC are wider and deeper, in the hardfacing alloys with added TiC, the diffusely distributed TiC increased the resistance of abrasive particles cutting, made the grooves shallower, reduced the cracking and spalling of eutectic carbides during the wear process, significantly improved the resistance of hardfacing alloys to abrasive wear. The resistance to abrasive wear performance of TiC hardfacing alloy introduced by in-situ synthesis was 5.2 times higher than that of hardfacing alloy without TiC addition. The surfaces of three kinds of hardfacing alloys after the impact-abrasion test have similar characteristics, due to the periodic impact of abrasive particles leading to hardfacing alloys plastic deformation and work-hardening so that their strength and hardness rose, plasticity and toughness declined, with the continued impact of abrasive particles, cracking occurred in the material and the cracks continue to extend within the material causing it to spalled. The hardness of added TiC hardfacing alloys was higher, can more effectively resist the embedding of abrasive particles, and reduce the generation and expansion of cracks due to the abrasive particles impact on the surface of the material generated by the plastic deformation, the resistance to impact-abrasion performance is more excellent. The resistance to impact-abrasion of TiC hardfacing alloy introduced by in-situ synthesis was 1.2 times higher than that of hardfacing alloy without TiC addition. The resistance to abrasive wear and impact-abrasion of the hardfacing alloy with in-situ precipitation of TiC is better than that of the hardfacing alloy with the direct addition of TiC to the powder core. TiC significantly improved the resistance to abrasive wear performance and impact-abrasion performance of the hardfacing alloy, in which the performance of the hardfacing alloy with in-situ precipitation of TiC is more excellent, which can provide a reference for the research and application of TiC in wear-resistant coatings for Soil-engaging components of agricultural machinery.
Keyword :
impact-abrasion impact-abrasion abrasive wear abrasive wear TiC TiC hypoeutectic high chromium cast iron hypoeutectic high chromium cast iron flux-cored welding wire flux-cored welding wire
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GB/T 7714 | Ma, Xiaohan , He, Dingyong , Qin, Zhiheng et al. Effects of TiC on the Microstructure and Wear Resistance of Hypoeutectic Fe-Cr-C Hardfacing Alloy [J]. | CHINA SURFACE ENGINEERING , 2024 , 37 (4) : 142-150 . |
MLA | Ma, Xiaohan et al. "Effects of TiC on the Microstructure and Wear Resistance of Hypoeutectic Fe-Cr-C Hardfacing Alloy" . | CHINA SURFACE ENGINEERING 37 . 4 (2024) : 142-150 . |
APA | Ma, Xiaohan , He, Dingyong , Qin, Zhiheng , Wang, Guohong , Xu, Yi , Yu, Jinman . Effects of TiC on the Microstructure and Wear Resistance of Hypoeutectic Fe-Cr-C Hardfacing Alloy . | CHINA SURFACE ENGINEERING , 2024 , 37 (4) , 142-150 . |
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Abstract :
本发明公开了一种竹笋结构W‑Zr基非晶合金复合材料及其制备方法与应用,涉及金属复合材料技术领域,复合材料的整体结构上分别存在硬脆区和软韧区,其中硬脆区体积分数为10%~30%,软韧区体积分数为70%~90%,两区域呈锥形交替分布,其分布为仿生竹笋结构,这种竹笋结构的优势在于:在高应变速率条件下,软韧区先发生变形,随着变形程度增加,软韧区与硬脆区同时变形,随后硬脆区开裂,沿着设计结构方式分离脱落,重新露出尖锐区域完成自锐化,类似竹笋剥落;循环此步骤,完成侵彻过程,可显著增加穿甲弹威力。
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GB/T 7714 | 谈震 , 席钊 , 宁子阳 et al. 一种竹笋结构W-Zr基非晶合金复合材料及其制备方法与应用 : CN202310055654.3[P]. | 2023-01-17 . |
MLA | 谈震 et al. "一种竹笋结构W-Zr基非晶合金复合材料及其制备方法与应用" : CN202310055654.3. | 2023-01-17 . |
APA | 谈震 , 席钊 , 宁子阳 , 贺定勇 , 周正 , 郭星晔 et al. 一种竹笋结构W-Zr基非晶合金复合材料及其制备方法与应用 : CN202310055654.3. | 2023-01-17 . |
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Abstract :
PurposeThe selective laser melting (SLM) technique, as a typical additive manufacturing process, is widely used for the fabrication of metallic biomedical components. In terms of biodegradability, zinc and its alloys represent an emerging generation of metallic materials for biomedical implants. The purpose of this paper is to obtain the Zn and Zn10Mg alloys with high mechanical properties using the SLM technology. The relationship between the processing parameters and the porosity of pure Zn and Zn10Mg alloy samples was investigated. Design/methodology/approachThe samples were fabricated using SLM technology working in an inert gas closed chamber. Preliminary experiments were conducted to analyze the laser power and gas flow on evaporation, single track form and porosity. To evaluate the influence of factors on relative density, the response surface methodology was applied. FindingsThe satisfactory results of the proposed method were achieved, in which the relative density of the components reached up to 99.63%, and compression strength reached 214 & PLUSMN; 13 MPa under optimal processing conditions. Originality/valueZinc is categorized by its low melting and boiling point, which leads to the high porosity of the components. It is difficult to prepare the Zn alloy samples with high relative density using SLM technology. This work successfully achieved dense Zn and Zn10Mg samples and investigated their microstructure, mechanical properties and corrosion behavior.
Keyword :
Mechanical properties Mechanical properties Pure Zn powders Pure Zn powders Selective laser melting Selective laser melting Zn10Mg alloy Zn10Mg alloy Additive manufacturing Additive manufacturing
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GB/T 7714 | Waqas, Muhammad , He, Dingyong , Tan, Zhen et al. A study of selective laser melting process for pure zinc and Zn10mg alloy on process parameters and mechanical properties [J]. | RAPID PROTOTYPING JOURNAL , 2023 , 29 (9) : 1923-1939 . |
MLA | Waqas, Muhammad et al. "A study of selective laser melting process for pure zinc and Zn10mg alloy on process parameters and mechanical properties" . | RAPID PROTOTYPING JOURNAL 29 . 9 (2023) : 1923-1939 . |
APA | Waqas, Muhammad , He, Dingyong , Tan, Zhen , Yang, Peng , Gao, Mu , Guo, Xingye . A study of selective laser melting process for pure zinc and Zn10mg alloy on process parameters and mechanical properties . | RAPID PROTOTYPING JOURNAL , 2023 , 29 (9) , 1923-1939 . |
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Abstract :
Strengthening low-chromium iron-based alloys with multiple alloy elements is a crucial strategy for developing "casing-friendly" hardbanding materials. In this paper, four kinds of low-chromium iron-based hardfacing alloys with different Ti contents were prepared by flux-cored arc welding technology, and the effect of Ti content on the microstructure, hardness, and wear performance under the abrasive wear and dry sliding wear was analyzed. The in situ TiC-reinforced iron-based hardfacing alloys exhibited microstructure comprising austenite, martensite, carbides, and in situ TiC particles. The in situ formation of TiC particles consumed the carbon in the alloy and thus raised the martensite start temperature, resulting in a reduction in the mass fraction of austenite and an increase in the martensite. Among the four hardfacing alloys, the alloy with 5 wt.% Ti exhibited the highest hardness (836.3 HV0.2) and the best wear resistance due to its highest martensite mass fraction (69.97 wt.%). The matrix with in situ TiC particles and martensite effectively resisted the cutting of abrasive grains and the wear mechanism developed from the microplowing in 0Ti alloy to microcutting in in situ TiC-reinforced iron-based hardfacing alloys in abrasive wear tests. In dry sliding wear tests, TiC particles were released and slid on the surface of the alloys, resulting in the formation of grooves, while the formation of the tribochemical reaction layers contributed to a reduction in the friction coefficient and wear rate. This study provides a theoretical foundation for the development of "casing-friendly" hardbanding materials.
Keyword :
Flux-cored arc welding Flux-cored arc welding Low-chromium iron-based hardfacing alloys Low-chromium iron-based hardfacing alloys In situ In situ Wear resistance Wear resistance TiC TiC
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GB/T 7714 | Tong, Zhixiang , Shao, Wei , He, Chengxing et al. Microstructure and wear resistance of in situ TiC-reinforced low-chromium iron-based hardfacing alloys [J]. | WELDING IN THE WORLD , 2023 , 68 (3) : 605-620 . |
MLA | Tong, Zhixiang et al. "Microstructure and wear resistance of in situ TiC-reinforced low-chromium iron-based hardfacing alloys" . | WELDING IN THE WORLD 68 . 3 (2023) : 605-620 . |
APA | Tong, Zhixiang , Shao, Wei , He, Chengxing , He, Dingyong . Microstructure and wear resistance of in situ TiC-reinforced low-chromium iron-based hardfacing alloys . | WELDING IN THE WORLD , 2023 , 68 (3) , 605-620 . |
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Abstract :
Thermal barrier coatings (TBCs) are widely used in the hot-section components of gas-turbine engines to allow operation at higher temperatures (> 1 200 degrees C), which has created some new issues. One issue is the spallation and premature failure of TBCs caused by calcium-magnesium-alumino-silicate (CMAS) deposits, which arise from entry of siliceous debris such as fly ash, sand, dust, and volcanic ash into engines. Since 1953, over 130 jet aircraft have encountered volcanic ash clouds, with varying degrees of damage and endangering the lives of many passengers. The 2010 eruption of Eyjafjallajokull volcano in Iceland led to the most severe air-traffic disruption since World War II. The operational response produced economic losses approaching 1.7 billion. When these debris enter the hot-section airfoil, they melt and are accelerated from low speed (similar to 15 m / s) to near supersonic speed (similar to 300 m / s), impacting and adhering to the TBC surface. Even with only a few molten silicate ash droplets adhering to the surface of hot-section airfoils, an initial deposit layer can form and large melt pockets (several cubic centimeters in volume) can accumulate. Such deposits can 1) block cooling holes and air flow paths, and 2) react with the top coating of hot-section airfoils. Furthermore, adhering droplets infiltrate the interior of TBCs under capillary forces. Due to the thermal gradient and thermal cycling, the infiltrated CMAS solidifies and fills in the microcracks, pores, and grain boundaries, resulting in loss of strain tolerance and increased coating stiffness. For traditional 7-8 wt.% yttria-stabilized zirconia (YSZ) material, chemical reaction with CMAS destroys the phase and structure stability. YSZ grains dissolve and Y-depleted ZrO2 grains precipitate due to the relatively low solubility of Zr4+ compared with Y3+ in melted CMAS. Upon cooling, the newly formed grains transform from tetragonal (t) to monoclinic (m) phases, accompanied by a 3%-4% volume expansion. As turbine inlet temperatures improve and industry production grows, TBCs are suffering from severe CMAS corrosion. This issue limits further application and development of TBCs; enhancing anti-corrosion performance of TBCs has become a concern. Herein, we compare the room-temperature and high-temperature properties of different CMAS and study the failure mechanism of TBCs exposed to CMAS. We also determine the most effective CMAS protection method. The results show that the chemical compositions, especially the Ca:Si ratio, of CMAS such as volcanic ash, dust and sand are different, further affecting their high-temperature viscosities and melting behaviors. With infiltration of molten CMAS toward the coating interior, chemical reaction occurs between them, resulting in instability of the coating microstructure and properties, and failure. Significant methods including inert-layer, rare-earth doping and novel materials have been proposed to improve the CMAS corrosion resistance of TBCs. The research and future development directions of CMAS corrosion and protection are proposed, providing a reference for design of novel TBCs.
Keyword :
advanced aero-engines advanced aero-engines thermal barrier coatings(TBCs) thermal barrier coatings(TBCs) corrosion protection corrosion protection calcium-magnesium-alumino-silicate(CMAS) calcium-magnesium-alumino-silicate(CMAS)
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GB/T 7714 | Wu, Yang , Guo, Xingye , He, Dingyong . Research Progress of CMAS Corrosion and Protection Method for Thermal Barrier Coatings in Aero-engines [J]. | CHINA SURFACE ENGINEERING , 2023 , 36 (5) : 1-13 . |
MLA | Wu, Yang et al. "Research Progress of CMAS Corrosion and Protection Method for Thermal Barrier Coatings in Aero-engines" . | CHINA SURFACE ENGINEERING 36 . 5 (2023) : 1-13 . |
APA | Wu, Yang , Guo, Xingye , He, Dingyong . Research Progress of CMAS Corrosion and Protection Method for Thermal Barrier Coatings in Aero-engines . | CHINA SURFACE ENGINEERING , 2023 , 36 (5) , 1-13 . |
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Abstract :
本发明涉及一种具有低热导率和高热稳定性的高熵硅酸盐陶瓷及其制备方法与应用。高熵陶瓷材料的化学式为RE2Si2O7,其中RE可为Er,Sc,Lu,Yb或Tm中的任意四种稀土元素。制备方法为:以四种RE2O3粉体和纯SiO2粉体为原料,以丙酮或无水乙醇为混合介质,用高能球磨机混合,充分混合的粉末经过烘干、研磨、筛分后,选取筛分后的细粉,在1500~1600℃的温度范围煅烧合成高熵陶瓷材料,然后采用放电等离子烧结法制备致密的块材陶瓷。所制备的陶瓷块材的致密度可达98%以上,经测量该材料具有非常低的热导率,在室温到1000℃范围内热导率均小于1.1W/m.K,可以用作防隔热材料。
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GB/T 7714 | 贺定勇 , 欧克 , 郭星晔 et al. 一种具有低热导率和高热稳定性的高熵硅酸盐陶瓷及其制备方法与应用 : CN202210112836.5[P]. | 2022-01-29 . |
MLA | 贺定勇 et al. "一种具有低热导率和高热稳定性的高熵硅酸盐陶瓷及其制备方法与应用" : CN202210112836.5. | 2022-01-29 . |
APA | 贺定勇 , 欧克 , 郭星晔 , 崔丽 , 周正 , 谈震 et al. 一种具有低热导率和高热稳定性的高熵硅酸盐陶瓷及其制备方法与应用 : CN202210112836.5. | 2022-01-29 . |
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Abstract :
In this study, newly developed NiCrB and conventional NiCrTi coatings were produced by arc spraying using compressed air and nitrogen as atomization gases. In this way, four coatings with different oxide contents were produced. The coatings were investigated in terms of their phase compositions, oxygen contents, and microstructures. The results showed that the oxygen contents in coatings were pronouncedly reduced by nitrogen-atomized compared to air-atomized. The oxygen contents in the nitrogen-atomized coatings were about one-fourth of those in the corresponding air-atomized coatings, respectively. No significant oxide phases were observed in the XRD patterns of the nitrogen-atomized coatings. Moreover, the corrosion behavior of the coatings was studied using a hot corrosion test in molten Na2SO4-10 wt.% NaCl salt at T = 800 degrees C. All coatings were significantly corroded under this test condition. However, NiCrB coatings exhibited higher corrosion resistance than NiCrTi coatings. The NiCrB and NiCrTi coatings prepared by nitrogen atomization corroded more severely in the initial stage than the corresponding coatings prepared by air atomization. The NiCrB coating with air-atomized showed the best corrosion resistance due to the low chromium content and the addition of boron.
Keyword :
NiCrB and NiCrTi coatings NiCrB and NiCrTi coatings microstructure microstructure oxide content oxide content arc spraying arc spraying hot corrosion hot corrosion
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GB/T 7714 | Wang, Xu , He, Dingyong , Zhou, Zheng et al. Hot Corrosion Behavior of Arc-Sprayed NiCrB and NiCrTi Coatings with Different Oxide Contents [J]. | COATINGS , 2022 , 12 (4) . |
MLA | Wang, Xu et al. "Hot Corrosion Behavior of Arc-Sprayed NiCrB and NiCrTi Coatings with Different Oxide Contents" . | COATINGS 12 . 4 (2022) . |
APA | Wang, Xu , He, Dingyong , Zhou, Zheng , Shao, Wei , Guo, Xingye , Wang, Guohong . Hot Corrosion Behavior of Arc-Sprayed NiCrB and NiCrTi Coatings with Different Oxide Contents . | COATINGS , 2022 , 12 (4) . |
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Abstract :
开发了三种不同结构的Ni-20Al丝材,对其火焰喷涂工艺性和涂层微结构特征等进行分析,并与商用Metco 405NS丝材及所制备的涂层进行了对比.结果表明,丝材结构影响了火焰加热时热量由丝材表面向芯部的传导,导致丝材熔化状态产生显著差异,进而决定了喷涂焰流的稳定性以及相关涂层组织的均匀性.其中,采用轧制拉拔包丝技术制备的Ni-20Al丝材,呈现出优异的喷涂工艺稳定性,所制备的涂层组织均匀,平均显微硬度和结合强度分别可达348.3 HV0.05、62 MPa,与405NS丝材制备涂层性能基本一致,具备了较好的应用潜力.
Keyword :
微观组织结构 微观组织结构 Ni-20Al丝材 Ni-20Al丝材 火焰喷涂 火焰喷涂
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GB/T 7714 | 路洋 , 闫泽 , 周正 et al. Ni-20Al丝材制备及涂层微结构特征研究 [J]. | 热喷涂技术 , 2022 , 14 (3) : 64-73 . |
MLA | 路洋 et al. "Ni-20Al丝材制备及涂层微结构特征研究" . | 热喷涂技术 14 . 3 (2022) : 64-73 . |
APA | 路洋 , 闫泽 , 周正 , 王彦军 , 苗小锋 , 冀晓鹃 et al. Ni-20Al丝材制备及涂层微结构特征研究 . | 热喷涂技术 , 2022 , 14 (3) , 64-73 . |
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Abstract :
对3 mm厚TC4钛合金/15-5PH不锈钢异种材料进行了添加镍铝青铜(nickel aluminum bronze,NAB)过渡层的激光填充材料焊接,研究了NAB过渡层对接头成形、微观组织与力学性能的影响.结果表明,添加NAB过渡层的TC4钛合金/15-5PH不锈钢异种材料激光焊接获得了良好成形的全熔透接头,接头抗拉强度达290 MPa,接头钛合金侧界面层硬度为547.8 HV.接头钛合金侧界面由3种不同形态的金属间化合物层组成,其中脆性较小的Cu-Ti,Ni-Ti相的数量显著增多,而脆性高的Ti-Fe相数量明显减少,表明添加NAB过渡层抑制了接头钛合金侧界面脆性高的Ti-Fe相的形成.
Keyword :
钛合金 钛合金 激光焊 激光焊 力学性能 力学性能 不锈钢 不锈钢
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GB/T 7714 | 牛小男 , 崔丽 , 王鹏 et al. 镍铝青铜过渡层对钛合金/不锈钢异种材料激光焊接头组织与力学性能的影响 [J]. | 焊接学报 , 2022 , 43 (01) : 42-47,115-116 . |
MLA | 牛小男 et al. "镍铝青铜过渡层对钛合金/不锈钢异种材料激光焊接头组织与力学性能的影响" . | 焊接学报 43 . 01 (2022) : 42-47,115-116 . |
APA | 牛小男 , 崔丽 , 王鹏 , 贺定勇 , 曹庆 . 镍铝青铜过渡层对钛合金/不锈钢异种材料激光焊接头组织与力学性能的影响 . | 焊接学报 , 2022 , 43 (01) , 42-47,115-116 . |
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Abstract :
对3mm厚激光选区熔化成形(SLM)TC4钛合金对接接头进行了激光焊接工艺试验,研究了80J/mm和100J/mm两种能量输入对接头焊缝成形、微观组织及接头力学性能的影响。结果表明,在两种不同焊接能量输入条件下,激光焊接SLM成形TC4钛合金获得良好的焊缝成形,焊缝区的平均显微硬度分别为388.7HV及403.3HV,高于SLM成形TC4钛合金母材(370.6HV),接头的抗拉强度分别为1027MPa及1018MPa,略低于母材(1201MPa)。
Keyword :
激光焊接 激光焊接 激光选区熔化 激光选区熔化 力学性能 力学性能 接头组织 接头组织 TC4钛合金 TC4钛合金
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GB/T 7714 | 田天 , 崔丽 , 贺定勇 et al. 激光选区熔化成形TC4钛合金激光焊接头组织与力学性能 [J]. | 航空科学技术 , 2022 , 33 (04) : 102-107 . |
MLA | 田天 et al. "激光选区熔化成形TC4钛合金激光焊接头组织与力学性能" . | 航空科学技术 33 . 04 (2022) : 102-107 . |
APA | 田天 , 崔丽 , 贺定勇 , 吴旭 , 郭星晔 . 激光选区熔化成形TC4钛合金激光焊接头组织与力学性能 . | 航空科学技术 , 2022 , 33 (04) , 102-107 . |
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