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Acta Metallurgica Sinica(English letters) 2014年第5期27卷 862-868页

作者： shulin lü Shusen Wu Chong lin Ping An State Key laboratory of Materials Processing and Die & Mould Technology Huazhong University of Science and Technology

In this research, the in situ Si and Fe-rich particles reinforced Al matrix composites were fabricated by rheocasting （RC） process assisted with ultrasonic vibration （USV）. After USV treatment, the polygonal primary Si crystals were refined into particles with average diameter of about 15-23 μm, and the fraction of primary Si declined to about 5.4-6.5 vol%. The coarse plate-like δ-Al4（Fe,Mn）Si2 phase was transformed into fine particles with average diameter of about 17-20 μm, and the fraction of particle-like Fe-bearing particles is about 3.6-5.3 vol%. The ultimate tensile strength of the RC composites increases with the increase of Fe content at 350 ℃. The increase of the elevated temperature strength of the composites is mainly attributed to the refinement of δ-Al4（（Fe,Mn）Si2 phase and the increase of the volume fraction of the Fe-bearing compounds. Compared with the composites without USV, the RC composites assisted with USV have thinner mechanical mixing layer in wear test, which corresponds to smaller wear rate.

关键词： Fe-bearing phase Metal matrix composites Microstructure Properties Ultrasound

Improving thermal conductivity of Mg-Si-Zn-Cu alloy through minimizing electron scattering at phase interface

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Journal of Magnesium and Alloys 2024年第9期12卷 3717-3728页

作者： lu Chen shulin lü Jianyu li Wei Guo Shusen Wu State Key lab of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074PR China

The primary cause of the decrease in thermal conductivity of conventional thermal conductive magnesium alloys is electron scattering brought on by solute ***,the impact of phase interface on thermal conductivity of magnesium alloys is usually *** study has developed a Mg-Si-Zn-Cu alloy with high thermal conductivity that is distinguished by having a very low solute atom content and a significant number of phase *** thermal conductivity of the Mg^(-1).38Si-0.5Zn-0.5Cu alloy raises from its untreated value of 133.2 W/(m·K)to 142.2 W/(m·K),which is 91%of the thermal conductivity of pure *** is accomplished by subjecting the alloy to both 0.8wt%Ce modification and T6 heat *** morphology of eutectic Mg_(2)Si phase is changed by Ce modification and heat treatment,and as a result,the scattering of electrons at the Mg_(2)Si/Mg interface is reduced,resulting in increase of the alloy’s thermal conductivity.

关键词： Thermal conductivity Ce modification Mg_(2)Si Heat treatment

Preparation of Al matrix nanocomposites by diluting the composite granules containing nano-SiCp under ultrasonic vibaration

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Journal of Materials Science & Technology 2018年第9期34卷 1609-1617页

作者： shulin lü Pan Xiao Du Yuan Kun Hu Shusen Wu State Key laboratory of Materials Processing and Die & Mould Technology Huazhong University of Science and Technology

In this work, an efficient process by diluting the nano-SiCp/Al composite granules in the molten matrix under ultrasonic vibration（UV） was developed to prepare metal matrix nano-composites（MMNCs）.Millimeter-sized composite granules with high content of SiC particle（8 wt%） were specially fabricated by dry high-energy ball milling（HBM） without process control agent, and then remelted and diluted in molten Al alloy under UV. The MMNCs melt was finally squeeze cast under a squeeze pressure of 200 MPa, Microstructure of the composite granules during dry HBM was investigated, and the effect of UV on microstructure and mechanical properties of the MMNCs was discussed. The results indicate that nano-SiC particles are uniformly distributed in the nano-SiCp/Al composite granules, which are covered by vestures of pure Al. During diluting, nano-SiC particles released from the composite granules are quickly dispersed in the molten matrix by UV within 4 min. Microstructure of MMNCs is significantly refined under UV and squeeze casting, eutectic Si phase modified to fine islands with an average length of 1.4 μm. Tensile strength of the squeeze cast MMNCs with 1 wt% of nano-SiC particles is 269 MPa, which is improved by 25% compared with the A356 alloy matrix.

关键词： Al matrix nano-composites Dry high-energy ball milling Ultrasonic vibration Composite granules Microstructure

Preparation of a novel ultra-high strength Al–Si–Cu–Ni alloy at room/elevated temperature by squeeze casting combined with a new heat treatment process

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Progress in Natural Science:Materials International 2024年第4期34卷 690-701页

作者： shulin lü Shilong li Zhaoxiang Yan Shusen Wu Jianyu li Xiaoyuan Ji State Key lab of Materials Processing and Die & Mould Technology School of Materials Science and Engineering Huazhong University of Science and Technology

In this paper, the microstructure evolution and properties of squeeze-cast Al–8Si-1.5Cu–1Ni-0.5Mg-0.5Mn-0.2V-0.2Ti-0.2Zr alloy（hereafter, Al–Si–Cu–Ni alloy for short） were investigated under various solution processes,evaluating the mechanical properties at room and elevated temperatures for both as-cast and T6-treated *** results showed that following the optimal two-stage solution（i.e., solution at 510°C for 6 h + solution at 530°C for 8 h） and subsequent aging at 190°C for 10 h, referred to as the S530-T6 treatment, the Al–Si–Cu–Ni alloy exhibited excellent room/high temperature performance. The ultimate tensile strength（UTS）, yield strength（YS）and elongation of the alloy at room temperature were 410 MPa, 368 MPa and 1.5 %, and the UTS, YS and elongation of alloy at 300°C were 177 MPa, 170 MPa and 6 %, respectively. The increase in strength at room temperature is mainly attributed to the spheroidization of eutectic silicon and the precipitate strengthening aroused from uniformly dispersed nano-sized Q-Al4Cu2Mg8Si7, σ-Al5Cu6Mg2and θ'-Al2Cu phases, while the increase in strength at high temperature is due to the formation of heat-resistant Ni-rich phases and the improvement of the micromorphology of high melting point intermetallic compounds.

关键词： Al-Si-Cu-Ni alloy Heat treatment Microstructure Squeeze casting Ultra-high strength

Research progress on microstructure evolution of semi-solid aluminum alloys in ultrasonic field and their rheocasting

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China Foundry 2014年第4期11卷 258-267页

作者： Wu Shusen lin Chong lü shulin Sha Meng State Key laboratory of Materials Processing and Die & Mould Technology Huazhong University of Science and Technology

The effects of ultrasonic vibration(UV)treatment on microstructure of semi-solid aluminum alloys and the application of UV in rheocasting process are *** semi-solid slurry can be produced by high-intensity UV process for aluminum *** microstructures of Al-Si,Al-Mg and Al-Cu alloys produced by rheocasting assisted with UV are compact and with fine *** mechanical properties of the UV treated alloys are increased by about 20%-30%.Grain refinement of the alloys is generally considered because of cavitation and acoustic streaming caused by *** from these mechanisms,a hypothesis of the fuse of dendrite root caused by capillary infiltration in the ultrasonic field,as well as a mechanism of crystallites falling off from the mould-wall and crystal multiplication by mechanical vibration effect in indirect ultrasonic vibration are proposed to explain the microstructure evolution of the alloys.

关键词： ultrasonic vibration aluminum alloy microstructure rheocasting

Synergistic effect of bonding heterogeneity and phonon localization in introducing excellent thermoelectric properties in layered heteroanionic NdZnSbO material

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Journal of Energy Chemistry 2025年第1期100卷 259-272页

作者： Da Wan Shuwei Tang shulin Bai Xiaodong li Peng Ai Wanrong Guo Tuo Zheng College of Materials Science and Engineering Liaoning Technical University Faculty of Chemistry Northeast Normal University

layered rare-earth metal oxides, harnessing the dual properties of oxides and two-dimensional layered materials, exhibit remarkable thermal stability and quantum confinement effects. Therefore, this work adopts the first-principles calculation combined with the Boltzmann transport theory to predict the thermoelectric properties of NdZnSbO compound. The coexistence of weak interlayer van der Waals interactions, robust intralayer ionic bonding, and partial covalent bonding leads to remarkable bonding heterogeneity, which engenders pronounced phonon scattering and imposes constraints on thermal transport along the out-of-plane direction. The weakened chemical bonds induced by the antibonding states, together with the rattling-like behavior of the Zn atom, culminate in the profound anharmonicity in the layered NdZnSbO compound. The weakening bond and heavy element contribute to the softness of phonon modes, which significantly diminishes the phonon group velocity. The redistribution-dominated four-phonon scattering process spans a large optical gap, which effectively reduces the lattice thermal conductivity. The NdZnSbO compound exhibits direct semiconductor characteristic with a bandgap of 0.73 e V by adopting the Heyd-Scuseria-Ernzerhof(HSE06) functional in combination with spin–orbit coupling(SOC) effect. The multi-valley feature of NdZnSbO compound augur favorably for band degeneracy, thus amplifying the power factor. Consequently, an optimal figure-of-merit(ZT) of 3.40 at 900 K is achieved for the n-type NdZnSbO compound. The present study delves deeply insights into the origins for the low thermal conductivity of NdZnSbO compound and proposes an optimization scheme to enhance overall thermoelectric performance.

关键词： Bond strength (chemical)

B2-CuZr相增强非晶复合材料组织调控研究进展

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稀有金属材料与工程 2023年第6期52卷 2253-2263页

作者：张震吕书林吴树森郭威华中科技大学材料科学与工程学院材料成形与模具技术国家重点实验室湖北武汉430074 湖南大学汽车车身先进设计及制造国家重点实验室湖南长沙410082 深圳华中科技大学研究院广东深圳518057

B2-CuZr相增强非晶合金因增强相特殊的“相变诱导塑性”而表现出优于传统增强相的综合力学性能,成为近年来材料领域的研究热点之一。然而原位自生B2-CuZr相的含量、尺寸及其分布难以调控,且铸造过程中易发生共析分解,限制了此类材料的... 详细信息

B2-CuZr相增强非晶合金因增强相特殊的“相变诱导塑性”而表现出优于传统增强相的综合力学性能,成为近年来材料领域的研究热点之一。然而原位自生B2-CuZr相的含量、尺寸及其分布难以调控,且铸造过程中易发生共析分解,限制了此类材料的应用范围。通过铸造工艺控制、合金成分调控及后处理等方法可有效解决上述问题。本文将对B2-CuZr相增强非晶复合材料的组织特点、增强机制及复合组织调控方法等方面进行综述,并对其未来发展进行简要展望。

关键词：非晶合金基复合材料原位自生B2-CuZr相组织调控力学性能

流变挤压铸造制备lPSO结构增强Mg-Zn-Y-Zr合金及其组织性能

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特种铸造及有色合金 2020年第1期40卷 1-6页

作者：吕书林杨雄吴树森华中科技大学材料成形与模具技术国家重点实验室武汉430074

采用流变挤压铸造工艺制备了含有lPSO结构的Mg99.9-3xZnxY2xZr0.1(x=0.5、1、2,摩尔分数,%)合金,研究了合金的微观组织特征及力学性能。结果表明,流变挤压铸造能有效细化合金的微观组织。合金的基体组织由尺寸较大的α1-Mg和尺寸较小的... 详细信息

采用流变挤压铸造工艺制备了含有lPSO结构的Mg99.9-3xZnxY2xZr0.1(x=0.5、1、2,摩尔分数,%)合金,研究了合金的微观组织特征及力学性能。结果表明,流变挤压铸造能有效细化合金的微观组织。合金的基体组织由尺寸较大的α1-Mg和尺寸较小的α2-Mg晶粒组成,lPSO结构呈细小的网状结构均匀地分布在晶界处,lPSO结构的含量越低,其细化效果越明显。随着挤压压力增大,合金中lPSO结构的厚度越来越小,当压力达到100MPa后,厚度变化趋缓。与常规重力铸造相比,流变挤压铸造能有效提高合金的力学性能,特别是伸长率。在400MPa下的流变挤压铸造Mg96.9Zn1Y2Zr0.1合金的抗拉强度和伸长率较重力铸造下分别提高了19%和170%。

关键词： Mg-Zn-Y-Zr合金 lPSO结构超声流变挤压铸造组织性能

超声功率对Mg-3RE-3Zn-0.7Y合金组织和力学性能的影响（英文）

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稀有金属材料与工程 2016年第1期45卷 7-12页

作者：方晓刚吴树森赵立吕书林安萍华中科技大学材料成形与模具技术国家重点实验室湖北武汉430074

如果在铸造过程能够细化含有稀土元素的金属间化合物,那么稀土镁合金在耐热应用方面将具有巨大的潜力。研究了半固态制浆过程中不同超声功率的超声振动对Mg-3RE-3Zn-0.7Y合金半固态微观组织以及铸态试样力学性能的影响。试验对液相线以... 详细信息

如果在铸造过程能够细化含有稀土元素的金属间化合物,那么稀土镁合金在耐热应用方面将具有巨大的潜力。研究了半固态制浆过程中不同超声功率的超声振动对Mg-3RE-3Zn-0.7Y合金半固态微观组织以及铸态试样力学性能的影响。试验对液相线以上20~40℃镁合金熔体分别施加超声功率为800 W至1200 W的超声振动,振动时间为90 s,结束超声振动温度为液相线以下10℃左右。结果表明,超声振动可以制备出组织中具有细小圆整的初生α-Mg相的优良半固态浆料,并且经过超声功率为1000 W的超声处理后浆料组织中初生α-Mg晶粒的平均晶粒直径和平均形状系数S F分别为55μm和0.63。此外,1000 W超声处理的铸件试样比未经超声处理的试样抗拉强度提高了25.2%,伸长率提高了93.5%。可见,声空化效应和声流效应使超声振动成为一种制备具有细小圆整初生晶粒镁合金半固态浆料的有效途径。

关键词： Mg-3RE-3Zn-0.7Y合金超声功率半固态浆料组织力学性能

干摩擦条件下超声流变压铸高铁过共晶Al-Si合金磨损性能研究

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摩擦学学报 2017年第2期37卷 176-184页

作者：林冲吴树森吕书林吴和保武汉工程大学机电工程学院湖北武汉430205 华中科技大学材料成形与模具技术国家重点实验室湖北武汉430074

采用销盘式摩擦磨损试验机对干摩擦条件下超声流变压铸成形Al-17Si-2Fe-2Cu-1Ni-0.8Mn合金的磨损性能进行了研究.结果表明:在相同载荷下,超声流变压铸试样的磨损率比液态压铸试样小.长板条状δ-Al4(Fe,Mn)Si2相的细化以及气孔的消除使... 详细信息

采用销盘式摩擦磨损试验机对干摩擦条件下超声流变压铸成形Al-17Si-2Fe-2Cu-1Ni-0.8Mn合金的磨损性能进行了研究.结果表明:在相同载荷下,超声流变压铸试样的磨损率比液态压铸试样小.长板条状δ-Al4(Fe,Mn)Si2相的细化以及气孔的消除使得合金的耐磨性能得以提高.当载荷从50 N增至100 N时,液态压铸和超声流变压铸试样的磨损率增幅均较大;当载荷从100 N增至150 N时,磨损率增幅变缓;当载荷从150 N增至200 N时,磨损率增幅又变大.合金在低载荷(50 N)时,磨损机理以氧化磨损为主;当载荷介于100~150 N之间时,以氧化磨损和剥层磨损相结合的方式为主;在高载荷(200 N)时,以剥层磨损为主.

关键词：干摩擦流变压铸高铁过共晶Al-Si合金磨损性能