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Preparation of high-strength Al-Mg-Si-Cu-Fe alloy via heat treatment and rolling

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International Journal of Minerals,Metallurgy and Materials 2014年第7期21卷 702-710页

作者： Chong-yu liu Peng-fei Yu Xiao-ying Wang Ming-zhen Ma ri-ping liu State Key Laboratory of Metastable Materials Science and Technology Yanshan University Key Laboratory of New Processing Technology for Nonferrous Metal & Materials Ministry of EducationGuilin University of Technology College of Materials Science and Engineering Guilin University of Technology

An Al-Mg-Si-Cu-Fe alloy was solid-solution treated at 560℃ for 3 h and then cooled by water quenching or furnace cooling. The alloy samples which underwent cooling by these two methods were rolled at different temperatures. The microstructure and mechanical properties of the rolled alloys were investigated by optical microscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction analysis, and tensile testing. For the water-quenched alloys, the peak tensile strength and elongation occurred at a rolling temperature of 180℃. For the furnace-cooled alloys, the tensile strength decreased initially, until the rolling temperature of 420℃, and then increased;the elongation increased consistently with increasing rolling temperature. The effects of grain boundary hardening and dislocation hardening on the mechanical properties of these rolled alloys decreased with increases in rolling temperature. The mechanical properties of the 180℃ rolling water-quenched alloy were also improved by the presence ofβ″phase. Above 420℃, the effect of solid-solution hardening on the mechanical properties of the rolled alloys increased with increases in rolling temperature.

关键词： aluminum alloys heat treatment rolling mechanical properties microstructure

High Performance ZrNbAl Alloy with Low Thermal Expansion Coefficient

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Chinese Physics Letters 2018年第8期35卷 54-57页

作者： Yun-Kai Zhou Xing Zhang Shu-Guang liu Ming-Zhen Ma ri-ping liu School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004 State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004

Thermal expansion is a common phenomenon in both metals and alloys, which is important for metallic material applications in modern industry, especially in nuclear and aerospace industries. A lower thermal expansion coefficient may cause lower thermal stress and higher accuracy. A new Zr-based alloy is developed and *** XRD diffraction results demonstrate that only a close-packed hexagonal phase（α or α＇ phase） exists in the microstructure. The thermal expansion and mechanical properties are studied. According to the experimental results, the new Zr-based alloy presents a low thermal expansion coefficient and good mechanical ***,its thermal expansion coefficient is stable through solution treatment.

关键词： Zr High Performance ZrNbAl Alloy with Low Thermal Expansion Coefficient XRD

Evaluation of casting fluidity and filling capacity of Zr-based amorphous metal melts

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Journal of Iron and Steel Research International 2018年第11期25卷 1163-1171页

作者： De-qiang Ma Xiao-zhao Ma Hong-yuan Zhang Ming-zhen Ma Xin-yu Zhang ri-ping liu Department of Electromechanical Engineering Tangshan UniversityTangshan 063000HebeiChina State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004 HebeiChina

Understanding the flow characteristics of amorphous metal melts is important for casting and molding *** of Zr-based amorphous metal melts was determined by using a self-designed *** analysis demonstrated that the fluidity test samples were fuUy amorphous *** onset crystallization temperature significantly moved toward high temperature with the increases of casting temperature,which improved the glass-forming ability and thermal stability of Zr-based amorphous *** test results demonstrated that the fluidity length increased monotonically with the increases of temperature,pressure,and runner *** identifying the types and quantities of the defect in castings,it could conclude that smooth filling processes occurred under appropriate *** results indicated that the flow behavior of the Zr-based amorphous metal melts strongly depended on the casting temperature and equivalent *** equation based on Newton's law of heat exchange and Rayleigh rule was established to'evaluate the fluidity of Zr-based amorphous metal *** calculations and experimental tests were basically coincided with each *** determined optimal casting temperatures and equivalent thicknesses were adopted to successfully fabricate a series of fully shaped castings through gravity casting.

关键词： Amorphous metal melt Casting Fluidity Constitutive equation Filling capacity

Fabrication,microstructures and mechanical properties of ZrO_2 dispersion-strengthened Q345 steel

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Transactions of Nonferrous Metals Society of China 2018年第6期28卷 1132-1140页

作者： Bao-an WANG Ning WANG Yu-jing YANG Hua ZHONG Ming-zhen MA Xin-yu ZHANG ri-ping liu State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhnangdao 066004China CNOOC Research Institute of Oil and Petrochemicals（Cri） Qingdao 266500China

ZrO2 dispersion-strengthened Q345 steel with different ZrO2 contents（0%, 0.5% and 1.2%, mass fraction） was fabricated through combining middle frequency induction furnace melting and cored-wire injection technologies. The microstructure and fracture surface morphology of ZrO2 dispersion-strengthened Q345 steel in casting, normalizing and quenching states were observed using optical microscopy, scanning electron microscopy and transmission electron microscopy. Also, strengthening and fracture mechanisms of the alloys were analyzed. Results showed that the dispersed ZrO2 particles added into Q345 matrix significantly enhanced its strength, and the main strengthening mechanism was the formation of dislocation cells and pinning effect caused by the addition of ZrO2 particles. Apart from that, the hard martensite phase, grain refinement and high ZrO2 particles content also played important roles in strengthening effect. Furthermore, the nanoindentation was also performed to further reveal the strengthening effect and mechanism of dispersed ZrO2 particles in Q345 steel. Results showed that the hardness of ZrO2 dispersion-strengthened Q345 steel increased with the increase of ZrO2 content.

关键词： Q345 steel ZrO2 particles dispersion strengthening microstructure mechanical properties

Numerical simulation and experimental verification of large-sized Zr-based bulk metallic glass ring-shaped parts in casting process

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Transactions of Nonferrous Metals Society of China 2022年第2期32卷 581-592页

作者： Fei-long WANG Qiu-hong HAO Peng-fei YU Yu-jing YANG Ming-zhen MA Xin-yu ZHANG ri-ping liu State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China Wuhan Hgcyber Data System Co. Ltd.Wuhan 430223China Department of Physics Hebei Normal University of Science and TechnologyQinhuangdao 066004China

An outer ring of 29320 self-aliging roller bearing was used in an experimental study on the casting of Zr_(41)Ti_(14)Cu_(12.5)Ni_(10)Be_(22.5) amorphous *** simulations of mold filling and solidification processes were carried out to determine the velocity fields and temperature fields of the alloy melt during mold filling process as well as the temperature fields and temperature gradient fields in the course of the *** to the results,a cast with a complete shape can be obtained at 1200℃under the condition that the cooling rate is greater than the critical cooling *** ring-shaped part with a thickness of 25 mm,an equivalent diameter of 22 mm,and a mass of 1.32 kg was prepared by gravity casting in a copper mold.X-ray diffraction and differential scanning calorimetry data revealed that the produced cast had the amorphous structure.

关键词： bulk metallic glasses ring-shaped part casting forming numerical simulation mold filling solidification

Influence of temperature and strain rate on hot deformation behavior of Zr_(50)Ti_(50) alloy in single β field

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Transactions of Nonferrous Metals Society of China 2016年第8期26卷 2086-2093页

作者： Yun-kai ZHOU Zhi-hao FENG Chao-qun XIA Wen-chang liu Qin JING Shun-xing LIANG Ming-zhen MA Zhi-guo ZHANG Xin-yu ZHANG ri-ping liu State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004 China College of Equipment Manufacture Hebei University of Engineering Handan 056038 China

The deformation behavior and microstructure of the Zr50Ti50 alloy in β phase field were investigated by isothermal compression tests at temperatures ranging from 700 to 850 °C and strain rates ranging from 0.001 to 1 s?1. The flow curves exhibited typical flow softening. The initial discontinuous yielding behavior was observed at higher strain rates, which was not found in other traditional Zr alloys. The apparent deformation activation energy was calculated to be 103 kJ/mol and constitutive equationdescribing the flow stress as a function of the strain rate and deformation temperature was proposed. The analysis indicated that the hot deformation mechanism was mainly dominated by dynamic recovery. However, dynamic recrystallization was delayed by dynamic recovery. Thereafter, the processing map was calculated to evaluate the efficiency of the forging process at the temperatures and strain rates investigated and to optimize processing parameters of hot deformation. The optimum processing parameters were found to be 830?850 °C and 0.56?1 s?1 for hot the deformation of Zr50Ti50 alloy in the β phase region.

关键词： Zr alloy hot deformation apparent activation energy microstructure processing map

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Ti基块体非晶合金在酸性溶液中的腐蚀行为

Transactions of Nonferrous Metals Society of China 2024年第3期34卷 874-889页

作者：杨靓张浩然张山施志林韦超马明臻刘日平燕山大学亚稳材料制备技术与科学国家重点实验室秦皇岛066004 燕山大学理学院秦皇岛066004

研究Ti_(34.3)Zr_(31.5)Cu_(5)Ni_(5.5)Be_(23.7)块体非晶合金在不同浓度HCl和H_(2)SO_(4)溶液中的腐蚀行为。电化学测试与扫描电子显微镜分析发现,在极化过程中,Cl^(-)离子在HCl溶液中引发点蚀损伤,点蚀电位随溶液浓度的增大而降低,被... 详细信息

研究Ti_(34.3)Zr_(31.5)Cu_(5)Ni_(5.5)Be_(23.7)块体非晶合金在不同浓度HCl和H_(2)SO_(4)溶液中的腐蚀行为。电化学测试与扫描电子显微镜分析发现,在极化过程中,Cl^(-)离子在HCl溶液中引发点蚀损伤,点蚀电位随溶液浓度的增大而降低,被腐蚀表面的损伤程度则与溶液浓度呈正相关。在H_(2)SO_(4)溶液中材料表面形成钝化膜,表现出良好的耐蚀性。X射线光电子能谱分析发现,随着HCl溶液浓度的增加,钝化膜的稳定性降低。通过浸泡实验得到4种材料的腐蚀速率。结果显示,Ti_(34.3)Zr_(31.5)Cu_(5)Ni_(5.5)Be_(23.7)块体非晶合金在HCl溶液中的耐腐蚀性能最好,其腐蚀速率为7.22×10^(-3) mm/a,约为316L不锈钢腐蚀速率的1/1294。

关键词：钛基块体非晶合金酸性溶液钝化膜腐蚀行为腐蚀速率

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基于熵和剪切带开发新型非晶合金

Science China Materials 2023年第11期66卷 4143-4164页

作者：冯士东宋贞强张宴会李子敬王利民刘日平 State Key Laboratory of Metastable Materials Science and Technology and College of Materials Science and EngineeringYanshan UniversityQinhuangdao 066004China Key Lab for Microstructural Material Physics of Hebei Province School of ScienceYanshan UniversityQinhuangdao 066004China Hebei Key Lab for Optimizing Metal Product Technology and Performance Yanshan UniversityQinhuangdao 066004China

非晶合金是非晶材料家族中的新成员,由于缺乏原子排列长程有序特征,具有独特的性能和广泛应用前景.然而,非晶合金的形成、成分设计和形变问题在该领域长期未得到解决,制约着新型非晶合金的高效开发.传统上,多组元非晶合金的成分设计主... 详细信息

非晶合金是非晶材料家族中的新成员,由于缺乏原子排列长程有序特征,具有独特的性能和广泛应用前景.然而,非晶合金的形成、成分设计和形变问题在该领域长期未得到解决,制约着新型非晶合金的高效开发.传统上,多组元非晶合金的成分设计主要遵循相图研究范式,以温度调控为出发点,确定低液相线的成分为落脚点,尤其强调深共晶成分.然而,对于缺乏相图的多组元体系则力所不及,亟需新的理论突破.本文综述了非晶转变中的热力学与动力学基本规律,重点探讨了热力学与动力学性质之间的关联性,尤其是梳理了材料熔化熵与熔点粘度、熔点等多个非晶形成经典参量之间的内在关联,提出并论证了熔化熵和振动熵为非晶形成的关键热力学参量,可有效指导高性能非晶合金的设计和表征.结合实际应用中对非晶材料的工程要求,讨论了化学成分调控对非晶合金剪切带的萌生密度和扩展稳定性的影响,并总结了在单调加载和疲劳加载条件下剪切带行为对非晶合金断裂过程的作用.最后展望了振动熵和构型熵之间争议问题,提出未来工作中需要发展具有物理意义玻璃形成能力指标和可靠数据库的需求,混合加载模式下的韧性以及疲劳和韧性之间的权衡等问题.本文为进一步建立高性能非晶材料成分设计路径提供了参考与指导.

关键词： amorphous alloys composition design entropy shear band

PtCu dendroframe octahedrons:Enhancing peroxidase-like activity and antibacterial efficiency through structural evolution

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Nano Research 2025年第1期18卷 100-106页

作者： ri Feng Jiuyi Hu Liangjun Wang Jiayu Xu Jiajia Li Zeeshan Ahmad Shaohui Zheng Muhammad Farhan Farid Wenjing liu Faisal Saleem Key Laboratory of Flexible Electronics(KLOFE) Institute of Advanced Materials(IAM)and School of Flexible Electronics(Future Technologies)Nanjing Tech UniversityNanjing 211816China

Nanozymes,which possess enzyme-like catalytic activity,are attractive alternatives to natural *** activity is largely dependent on the structure of the ***,challenges remain in optimizing the structure-activity *** work explores the synthesis and utilization of PtCu nanostructures(NSs),focusing on their peroxidase(POD)-like properties and their potential as antibacterial *** developed PtCu dendrites that transform into unique dendroframe octahedrons(DFOs)and subsequently stabilize into solid octahedrons with unusual growth *** intermediate DFO,showed higher POD-like activity in comparison to other shapes of PtCu *** DFOs also have the better ability to consume glutathione,thus enhancing their sterilization ***,we demonstrate the effectiveness of these PtCu DFOs as powerful antibacterial *** work provides valuable information on shape dependent activities of PtCu NSs in the field of biomedicine.

关键词： nanozymes antibacterials peroxidase PtCu dendroframe octahedrons dendrites