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spinodal decomposition和它在形成某些有序结构中的作用

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物理 1983年第12期 718-723页

作者：李如生清华大学化学与化学工程系

New insights into the hardening and pitting corrosion mechanisms of thermally aged duplex stainless steel at 475℃:A comparative study between 2205 and 2101 steels

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Journal of Materials Science & Technology 2022年第3期98卷 123-135页

作者： R.Silva G.S.Vacchi C.L.Kugelmeier I.G.R.Santos A.A.Mendes Filho D.C.C.Magalhães C.R.M.Afonso V.L.Sordi C.A.D.Rovere Munir Rachid Corrosion Laboratory Department of Materials EngineeringFederal University of São CarlosRodovia Washington Luis Km 23513565-905 São CarlosSPBrazil Engineering Modeling and Applied Social Sciences Center(CECS)Federal University of ABCAvenida dos Estados 500109210580 Santo AndréSPBrazil Federal University of São Carlos Graduate Program in Materials Science and EngineeringBrazil

In this study,the relationship between spinodal decomposition and the formation of Ni-rich clusters and G-phase in the ferrite on hardening and pitting corrosion of two thermally aged duplex stainless steels(DSSs)at 475℃was *** indicate that,for 2205 DSS,pitting corrosion behavior is influenced by the presence and size of G-phase precipitates for longer aging times,but this contribution is masked by the advanced stage of spinodal decomposition in the ferritic *** the other hand,for 2101 DSS,the formation of Cr-richer nitrides impairs pitting corrosion resistance more than spinodal decomposition.

关键词： Duplex stainless steel spinodal decomposition G-phase precipitation Pitting corrosion Hardening

Atomic-scale characterization of multiple precipitating species in a precipitation-hardened martensitic stainless steel

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Journal of Iron and Steel Research(International) 2022年第2期29卷 207-214页

作者： Zhen-bao Liu Zhe Yang Jian-xiong Liang Zhi-yong Yang Guang-min Sheng Division of Special Steels Central Iron and Steel Research Institute(CISRI)Beijing100081China School of Material Science and Engineering Chongqing UniversityChongqing400044China

Multiple precipitating species in a 2.2 GPa grade precipitation-hardened martensitic stainless steel with balanced ductility were characterized at atomic scale by atom probe *** results indicated that the clustering of solute atoms was promoted with progressive aging treatments.(Cr,Mo)-rich carbide(M_(2)C)precipitated at the linear dislocations in the as-aged *** segregation of Cr,Mo,and C at phase boundaries favored the precipitation of carbide and caused the formation of Cr-lean *** decomposition of martensitic matrix during aging led to the substantial precipitation of fine Cr-rich(α′Cr)*** with the first aging treated samples,a synergistic enhancement of both strength and ductility of the secondary aging treated(SAT)samples was primarily ascribed to the enhanced precipitation of Cr-rich ***,Ni-rich filmy reversed austenite precipitated at the lath boundary,which was beneficial to the ductility of SAT samples.

关键词： Aging treatment Nanoprecipitate Atom probe spinodal decomposition Precipitation-hardened martensitic stainless steel

Influence of quenching medium on the dendrite morphology,hardness,and tribological behaviour of cast Cu-Ni-Sn spinodal alloy for defence application

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Defence Technology（防务技术） 2023年第12期30卷 83-100页

作者： Bipin Sankar Karthik V Shankar Vamu Sunil Hemanth Kashyap S Nikhil Nair Adarsh A.Nair Abhinav P M Department of Mechanical Engineering Amrita Vishwa VidyapeethamAmritapuriIndia

Cu-Ni-Sn spinodal alloys(spinodal bronze)are potential materials with robust applications in components associated with defence applications like bearings,propellers,bushes,and shafts of heavily loaded aircraft,off-road vehicles,and *** paper presents a comparative study using water,Brine solution,and SAE 40 oil as the quenching media in regular bronze(Cu-6Sn)and spinodal bronze(Cu-9Ni-6Sn)*** analysis was conducted by optical microscopy,transmission electron microscopy(TEM),and X-ray diffraction technique(XRD)on bronze and spinodal bronze samples immersed in the three different quenching media to understand the grain size and hardness values *** analysis was performed to analyze the effect of quenching media on the wear aspects of bronze and spinodal bronze *** hardness value of the brine-aged spinodal bronze samples was as high as 320 Hv,and the grain size was very low in the range of 60μm.A quantitative comparison between brine-aged regular bronze and brine-aged spinodal bronze showed that the hardness(Hv)was almost 80%higher for brine-aged spinodal ***,the grain size was approximately 30%finer for spinodal bronze when compared with regular *** the load was increased in spinodal bronze samples,there was an initial dip in wear rate followed by a marginal *** was a steady increase in friction coefficient with a rise in load for brine-aged regular bronze and spinodal bronze *** results indicate that brine solution is the most effective quenching medium for cast Cu-Ni-Sn spinodal alloys.

关键词： Quenching Water Brine SAE 40 oil Grain size Hardness Wear rate spinodal decomposition CuSn spinodal alloy CuNiSn

Oxygen-assisted spinodal structure achieves 1.5 GPa yield strength in a ductile refractory high-entropy alloy

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Journal of Materials Science & Technology 2023年第26期157卷 11-20页

作者： Dingcong Cui Yuyu Zhang Linxiang Liu Yue Li Lei Wang Zhijun Wang Junjie Li Jincheng Wang Feng He State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518063China

Refractory high-entropy alloys(RHEAs)with room-temperature ductility are drawing growing attention for potential high-temperature ***,the most widely used metallurgical mechanisms appear weak in optimizing their strength and ***,we report that the nanoscale spinodal struc-ture in Ti_(41)V_(27)Hf_(15)Nb_(15)O_(2)leads to the highest tensile yield strength(∼1.5 GPa)among the existing RHEAs and good elongation of∼12%.With the aid of thermodynamic calculations,we show that oxygen plays a dominant role in controlling the formation of the spinodal structure by influencing the spinodal gap of the Ti-V-Hf-Nb *** the atomic structure of the spinodal structure(β+β^(∗)),we showed that the large lattice misfit of the spinodal phases is mainly responsible for the excellent strengthen-ing effect while the planar to wavy dislocation glide mode transition accounts for the retained *** work provides a novel strategy to improve the mechanical properties of the RHEAs and deepens the understanding of their phase stabilities.

关键词： High entropy alloys spinodal decomposition Strengthening mechanisms

EFFECT OF HEATING RATE ON THERMO-INDUCED AGGREGATION OF POLY(ETHYLENE OXIDE)-b-POLY(N-ISOPROPYLACRYLAMIDE) IN AQUEOUS SOLUTIONS

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Chinese Journal of Polymer Science 2010年第3期28卷 437-447页

作者：梁德海 Beijing National Laboratory for Molecular Sciences and the Key Laboratory of Polymer Chemistry & Physics of Ministry of Education College of Chemistry & Molecular EngineeringPeking University

The effects of heating rate on the aggregate behavior of poly（ethylene oxide）-b-poly（N-isopropylacrylamide） in aqueous solutions were investigated in detail by laser light scattering and TEM. By employing two separate heating protocols, step-by-step heating at 〈 5 K/step and one-step jump, to heat the sample from 15℃ to the selected temperature, we found that the heating rate only showed significant effect on the aggregates above the cloud point. The aggregate formed by step-by-step heating exhibited a much larger size and a broader size distribution than those formed by one-step jump heating. Moreover, neither of the aggregates were ideal micellar structures as indicated by the size and the Rg/Rh values. On the contrary, at temperatures below the cloud point where the block copolymer formed core-shelled micelles, the heating rate showed negligible effect on the size and size distribution of the micelles. Since the system underwent a phase separation above the cloud point, the heating rate effect could be reasonably explained by the phase separation mechanisms： the nucleation-and-growth mechanism in the metastable region and the spinodal decomposition mechanism in the unstable region.

关键词： Heating rate Cloud point Nucleation-and-growth spinodal decomposition PEO-b-PNIPAm.

Phase separation and coarsening of NiAl(β′)intermetallic in quench-aged Fe-Ni-Al alloys

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Journal of Iron and Steel Research(International) 2020年第11期27卷 1331-1338页

作者： C.Ferreira-Palma J.A.Rosas-Barrios V.M.Lopez-Hirata D.I.Rivas-Lopez H.J.Dorantes-Rosales Faculty of Chemical Sciences Universidad VeracruzanaVeracruz 94294Mexico ESIQIE Instituto Politecnico Nacional.UPALMMexico City 07738Mexico

The coarsening behavior of four quench-aged Fe-Ni-AI alloys with different Ni and Al con tents is *** alloys were solubilized at 1100℃for 24 h,water-quenched and aged at 850℃for periods ranging from 1 to 100 h to promote phase separation and *** two alloys with the highest combined Ni and Al contents(>35 at.%)showed signs of spinodal decomposition,while the alloys with lower Ni and Al contents followed a classical nucleation *** Ni and Al contents promoted an increase in NiAl(β′)phase fraction in concordance with phase equilibrium *** alloy with the highest[3'fraction presented a completely interconnected *** coarsening ofβ′particles in the other three alloys followed the predictions of the Lifshitz-Slyozov-Wagner(LSW)*** general trend was an increase in the coarsening kinetics with higher Ni and Al *** highest hardness was found in the alloys with higher fraction albeit these compositions are less resistant to coarsening and have been reported to present a low room-temperature ductility.

关键词： Precipitation spinodal decomposition Coarsening Aging Fe-Ni-Al alloy

Effects of Chain Entanglement on Liquid-Liquid Phase Separation Behavior of LCST-type Polymer Blends: Cloud Point and decomposition Rate

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Chinese Journal of Polymer Science 2015年第6期33卷 869-879页

作者： Yu Lin 上官勇刚 Bi-wei Qiua Wen-wen Yu Feng Chen Zhen-wu Guo 郑强 MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang University Shanghai Key Laboratory of Advanced Polymeric Materials School of Materials Science and EngineeringEast China University of Science and Technology College of Modern Science and Technology China Jiliang University

By preparing homogenous blend samples with different degrees of chain entanglement, we report an anomalous contribution of chain entanglement to phase separation temperature and rate of poly（methyl methacrylate）/poly（styrene-co- maleic anhydride）（PMMA/SMA） blends presenting a typical lower critical solution temperature （LCST） behavior. The melt- mixed PMMA/SMA blends with a higher chain entanglement density present a lower cloud point （To） and shorter delay time, but lower phase separation rate at the given temperature than solution-cast ones, suggesting that for the polymer blends with different condensed state structure, thermodynamically more facilitation to phase separation （lower Tc） is not necessarily equivalent to faster kinetics （decomposition rate）. The experimental results indicate that the lower Tc of melt-mixed sample is ascribed to smaller concentration fluctuation wavelength （Am） induced by higher entanglement degree, while higher entanglement degree in melt-mixed sample leads to a confined segmental dynamics and consequently a slower kinetics （decomposition rate） dominated by macromolecular diffusion at a comparable quench depth. These results reveal that the chain packing in polymer blends can remarkably influence the liquid-liquid phase separation behavior, which is a significant difference from decomposition of small molecular mixtures.

关键词： Chain entanglement spinodal decomposition Concentration fluctuation Segmental dynamics.

Microstructure and properties of Cu-2.8Ni-0.6Si alloy

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Rare Metals 2013年第3期32卷 228-233页

作者： Xiang-Peng Xiao Bai-Qing Xiong Guo-Jie Huang Lei Cheng Li-Jun Peng Qi-Ming Liang State Key Laboratory for Fabrication and Processing of Nonferrous Metals General Research Institute for Nonferrous Metals China Nonferrous Metals Processing Technology Albetter Albronze Co. Ltd.

The phase transformation behavior and heat treatment response of Cu-2.8Ni-0.6Si （wt%） alloy sub- jected to different heat treatments were studied by X-ray diffraction, transmission electron microscopy observation, and measurement of hardness and electrical conductivity. The variation of hardness and electrical conductivity of the alloy was measured as a function of aging time. On aging at the temperature below TR （500-550 ℃） in Cu-2.8Ni-0.6Si alloy, the transformation undergoes spinodal decomposi- tion, DO22 ordering, and δ-NiaSi phase. On aging at the temperature above TR （500-550 ℃）, the transformation products were precipitations of 8-Ni2Si. The free energy versus composition curves were employed to explain the microstructure observations.

关键词： Microstructure Hardness Electricalconductivity spinodal decomposition DO22 ordering