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Effects of second phases on mechanical properties and martensitic transformations of ECAPed TiNi and Ti-Mo based shape memory alloys 被引量:8
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作者 宋杰 王立明 +5 位作者 张效宁 孙小刚 江鸿 范志国 谢超英 吴明雄 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第8期1839-1848,共10页
TiNi and Ti-based shape memory alloys were processed by equal channel angular pressing (ECAP) at 673-773 K along Bc route to obtain ultrafine grains for increasing the strength of parent phase and improving the func... TiNi and Ti-based shape memory alloys were processed by equal channel angular pressing (ECAP) at 673-773 K along Bc route to obtain ultrafine grains for increasing the strength of parent phase and improving the functional properties. The effects of both thermodynamically stable and metastable second phases on the mechanical properties and martensitic transformations of these alloys were investigated. It is found that thermodynamically stable Ti2Ni phase has no effect on martensitic transformation and superelasticity of Ti-rich TiNi alloy, thermodynamically stable α phase is harmful for ductility of Ti-Mo-Nb-V-Al alloy, but metastable Ti3Ni4 phase is effective for R phase transformation, martensitic transformation and superelasticity of Ni-rich TiNi alloy. The mechanisms of the second phases on the martensitic transformations and mechanical properties were discussed. 展开更多
关键词 TiNi alloy Ti-Mo based shape memory alloy equal channel angular pressing (ECAP) second phase mechanical property
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Evolution of second phases and mechanical properties of 7075 Al alloy processed by solution heat treatment 被引量:26
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作者 Xiu-liang ZOU Hong YAN Xiao-hui CHEN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第10期2146-2155,共10页
The effects of solution treatment on the evolution of the second phases and mechanical properties of7075Al alloy werestudied with scanning electron microscopy(SEM),energy dispersive X-ray spectrometry(EDS),differentia... The effects of solution treatment on the evolution of the second phases and mechanical properties of7075Al alloy werestudied with scanning electron microscopy(SEM),energy dispersive X-ray spectrometry(EDS),differential scanning calorimetry(DSC),hardness and tensile tests.The results show that Mg(Zn,Cu,Al)2phases gradually dissolve into the matrix,yet the size andmorphology of Al7Cu2Fe phase exhibit no change with the increase of the solution treatment temperature and time due to its highmelting point.When the solution treatment temperature and time continue to increase,the formation of coarse black Mg2Si particlesoccurs.Compared to the as-cast alloy,the microhardness,tensile strength,and elongation of the sample under solution heat treatmentat460°C for5h are increased by55.1%,40.9%and109.1%,respectively.This is because the eutectic Mg(Zn,Cu,Al)2phases almostcompletely dissolve and basically no coarse black Mg2Si particles are formed. 展开更多
关键词 solution treatment microstructure evolution second phases mechanical properties 7075 Al alloy
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Effect of ECAP processing on distribution of second phase particles,hardness and electrical conductivity of Cu-0.81Cr-0.07Zr alloy 被引量:6
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作者 Filipe CALDATTO DALAN Gisele Ferreira de LIMA ANDREANI +3 位作者 Dilermando Nagle TRAVESSA Ilshat Albertovich FAIZOV Svetlana FAIZOVA Kátia Regina CARDOSO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第1期217-232,共16页
The effect of equal-channel angular pressing(ECAP)processing at room temperature and 300℃on the distribution of the second phase particles and its influence on hardness and electrical conductivity of the commercial C... The effect of equal-channel angular pressing(ECAP)processing at room temperature and 300℃on the distribution of the second phase particles and its influence on hardness and electrical conductivity of the commercial Cu-0.81Cr-0.07Zr alloy were investigated.Microstructural characterization indicated that the area fraction of coarse Cr-rich particles decreased after ECAP processing.This reduction was attributed to the Cr dissolution induced by plastic deformation.The electrical conductivity of the alloy decreased by 12%after 4 ECAP passes at room temperature due to the increase of electrons scattering caused by higher Cr content in solid solution and higher density of defects in the matrix.These results were supported by the reduction of the Cu lattice parameter and by the exothermic reactions,during differential scanning calorimetry(DSC)analysis,observed only in the samples subjected to ECAP processing.Aging heat treatment after ECAP processing promoted an additional hardening effect and the complete recuperation of the electrical conductivity,caused by the re-precipitation of the partially dissolved particles.The better combination of hardness(191 HV)and electrical conductivity(83.5%(IACS))was obtained after 4 ECAP passes at room temperature and subsequent aging at 380℃for 1 h. 展开更多
关键词 ECAP Cu-Cr-Zr alloy second phase particles phase transition
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Different role of second phase in the micro-galvanic corrosion of WE43 Mg alloy in NaCl and Na_(2)SO_(4) solution 被引量:5
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作者 Baojing Feng Guonan Liu +7 位作者 Peixu Yang Sensen Huang Dongqing Qi Peng Chen Chengduo Wang Jiang Du Shaojun Zhang Jinhui Liu 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2022年第6期1598-1608,共11页
Effect of the second phase in the micro-galvanic corrosion of a commercial Mg alloy containing rare earth elements, cast WE43 alloy,was investigated in 0.6 M NaCl solution and 0.6 M Na_(2)SO_(4)solution by scanning el... Effect of the second phase in the micro-galvanic corrosion of a commercial Mg alloy containing rare earth elements, cast WE43 alloy,was investigated in 0.6 M NaCl solution and 0.6 M Na_(2)SO_(4)solution by scanning electron microscopy(SEM) observations, scanning Kelvin probe force microscopy(SKPFM) analysis, hydrogen evolution, weight loss measurement, and electrochemical techniques. It is confirmed that the second phase of cast WE43 alloy is more active than Mg matrix and exhibits an anodic role in the micro-galvanic corrosion with α-Mg matrix as cathode and dissolves preferentially in Na_(2)SO_(4)solution, in contrast to the situation in NaCl solution. The corrosion rate of cast WE43 alloy in Na_(2)SO_(4)solution is much higher than that in NaCl solution, which is different from the conventional wisdom and could be attributed to the different role of the second phase in the micro-galvanic corrosion in two solutions. 展开更多
关键词 Mg rare earth alloy second phase Micro-galvanic corrosion Anode role Solution anion
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Effects of shape and size of second phase on mechanical properties of sintered Mo-Y_(2)O_(3) alloys 被引量:2
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作者 Zhuang-zhi WU Na ZHAO +4 位作者 Yao LU Hai-lang LIU Bo-hua DUAN Xin-li LIU De-zhi WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第6期1926-1934,共9页
The morphology and size of second phase greatly influence the strengthening effect on oxidation dispersion strengthened Mo alloys.In this work,a novel nanostructuring strategy is adopted to modify the second phase of ... The morphology and size of second phase greatly influence the strengthening effect on oxidation dispersion strengthened Mo alloys.In this work,a novel nanostructuring strategy is adopted to modify the second phase of Y_(2)O_(3),and the corresponding effects of particle shape and size on mechanical properties of sintered Mo−Y_(2)O_(3) alloys were investigated.It is found that spherical particles with sizes below 200 nm are preferred due to the dominant intragranular distribution of second phases associated with better strengthening effect originating from dislocation pinning.With smaller particle size of Y_(2)O_(3) nanospheres(105 nm),the tensile strength of corresponding Mo alloy is enhanced by about 43.8%,much higher than that(8.3%)reinforced by second phase nanospheres with larger particle size(322 nm).Meanwhile,with similar particle size(around 100 nm),the spherical shape exhibits better strengthening effect than the one reinforced by one-dimensional rod-like second phase. 展开更多
关键词 Mo-based alloys second phase yttrium oxide mechanical properties dispersion strengthening
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Phase-field study of the second phase particle effect on texture evolution of polycrystalline material 被引量:1
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作者 卢艳丽 张刘超 +1 位作者 周影影 陈铮 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第6期639-643,共5页
The second phase particle effect on texture evolution of polycrystalline material is studied through phase-field method. A unique field variable is introduced into the phase-field model to represent the second phase p... The second phase particle effect on texture evolution of polycrystalline material is studied through phase-field method. A unique field variable is introduced into the phase-field model to represent the second phase particles. Elastic interaction between particles and grains is also considered. Results indicate that in the presence of second phase particles the average particle diameter turns smaller than in the absence of these particles and retards texture formation by pinning effect. The second phase particles change the strain energy profile, which tremendously influences the pinning effect. 展开更多
关键词 texture evolution second phase particles elastic energy phase-field method
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Effects of second phases on fracture behavior of Mg-10Gd-3Y-0.6Zr alloy 被引量:1
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作者 林丹 王磊 +2 位作者 孟凡强 崔建忠 乐启炽 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第B07期421-425,共5页
The effects of second phases on the fracture behavior of Mg-10Gd-3Y-0.6Zr alloy were investigated.The results show that the fracture mode can be generally described as ductile transgranular fracture in as-extruded con... The effects of second phases on the fracture behavior of Mg-10Gd-3Y-0.6Zr alloy were investigated.The results show that the fracture mode can be generally described as ductile transgranular fracture in as-extruded condition and intergranular fracture in peak-aged condition.In as-extruded condition,the ductile transgranular fracture occurs by the formation and transgranular propagation of the microcrack from the broken primary phases.However,as the collaboration effects of precipitates inside grains and on the grain boundaries have the tendency to reduce the cohesive strength of the grain boundary,and make the grain boundaries the favorable path for crack propagation,the intergranular fracture occurs in peak-aged condition. 展开更多
关键词 Mg-Gd-Y-Zr alloy second phases MICROSTRUCTURE FRACTURE tensile properties
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Grain growth simulation with the second phase particle pinning for heat-affected zone of microalloyed steel welds 被引量:1
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作者 陈翠欣 李午申 《China Welding》 EI CAS 2006年第4期63-66,共4页
The second phase particle dispersed in microalloyed steel has different effects on grain growth depending on their size and volume fiaction of the second phase particles which will change during welding thermal cycles... The second phase particle dispersed in microalloyed steel has different effects on grain growth depending on their size and volume fiaction of the second phase particles which will change during welding thermal cycles. The particle coarsening and dissolution kinetics model was analyzed for continuous heating and cooling. In addition, based on experimental data, the coupled equation of grain growth was established by introducing limited size of grain growth with the consideration of the second phase particles pinning effects. Using Monte Carlo method based on experimental data model, the grain growth simulation for heat-affected zone of microalloyed steel welds was achieved. The calculating results were well in agreement with that of experiments. 展开更多
关键词 microalloyed steel the second phase particle grain growth pinning effect SIMULATION
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The second phase cofferdam of Three Gorges Project was started to dismantle
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《Electricity》 2001年第4期52-52,共1页
关键词 PROJECT The second phase cofferdam of Three Gorges Project was started to dismantle
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CALCULATION OF SECOND PHASE PARTICLE-GRAIN BOUNDARY INTERACTION RANGE 被引量:6
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作者 X.L. Wang Y.H. Wei +1 位作者 W. Wang L.F. Hou 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2008年第1期8-14,共7页
On the basis of the grain boundary equation by HeUman and corresponding analysis of Worner, this article deals with the interaction range between the second-phase particle (SPP) and grain boundary (GB) as viewed f... On the basis of the grain boundary equation by HeUman and corresponding analysis of Worner, this article deals with the interaction range between the second-phase particle (SPP) and grain boundary (GB) as viewed from the applicability of grain boundary equation. Also, a new expression describing the interaction range has been derived, which solves the problem in theory that the interaction range between SPP and GB can only be qualitatively analyzed previously. It is shown that given the interaction position between SPP and GB, the interaction range can be quantitatively determined by use of this expression. 展开更多
关键词 second-phase particle Grain boundary Pinning force Surface free energy
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Influence of Varying Crude Protein Levels and Balanced Amino Acids on the Performance and Haematological Characteristics of Laying Hens at the Second Phase of Production 被引量:1
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作者 Gbemiga Oladimeji Adeyemo 《Food and Nutrition Sciences》 2013年第1期11-15,共5页
Varying levels of dietary crude proteins and balanced amino acids were fed to layers for a period of eight weeks starting from the twenty-sixth week of age of birds and six weeks into egg production. Effects on perfor... Varying levels of dietary crude proteins and balanced amino acids were fed to layers for a period of eight weeks starting from the twenty-sixth week of age of birds and six weeks into egg production. Effects on performance and haematological characteristics were investigated at this second phase of production. Sixty Black Nera hens were randomly allotted into four (4) dietary treatments, containing the following levels of crude protein 14%, 15%, 16%, 17% and the metabolizable energy was iso-caloric for each treatment. The results showed that there were no significant differences (P > 0.05) observed for lymphocyte, Haemoglobin (Hb), Packed Cell Volume (PCV), Red Blood Cell (RBC) and White Blood Cell (WBC), these haematological parameters were within the range for healthy birds. Thus crude protein level of 14% can be used in diets of layers at the second phase of production provided that adequate amino acids are given, without adverse effect on egg laying, feed intake and measured blood parameters. 展开更多
关键词 VARYING CRUDE Protein BALANCED Amino ACIDS LAYING HEN second phase
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Design biodegradable Zn alloys: Second phases and their significant influences on alloy properties 被引量:12
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作者 Zhang-Zhi Shi Xi-Xian Gao +5 位作者 Hai-Jun Zhang Xue-Feng Liu Hui-Yan Li Chao Zhou Yu-Xia Yin Lu-Ning Wang 《Bioactive Materials》 SCIE 2020年第2期210-218,共9页
Alloying combined with plastic deformation processing is widely used to improve mechanical properties of pure Zn.As-cast Zn and its alloys are brittle.Beside plastic deformation processing,no effective method has yet ... Alloying combined with plastic deformation processing is widely used to improve mechanical properties of pure Zn.As-cast Zn and its alloys are brittle.Beside plastic deformation processing,no effective method has yet been found to eliminate the brittleness and even endow room temperature super-ductility.Second phase,induced by alloying,not only largely determines the ability of plastic deformation,but also influences strength,corrosion rate and cytotoxicity.Controlling second phase is important for designing biodegradable Zn alloys.In this review,knowledge related to second phases in biodegradable Zn alloys has been analyzed and summarized,including characteristics of binary phase diagrams,volume fraction of second phase in function of atomic percentage of an alloying element,and so on.Controversies about second phases in Zn-Li,Zn-Cu and Zn-Fe systems have been settled down,which benefits future studies.The effects of alloying elements and second phases on microstructure,strength,ductility,corrosion rate and cytotoxicity have been neatly summarized.Mg,Mn,Li,Cu and Ag are recommended as the major alloying elements,owing to their prominent beneficial effects on at least one of the above properties.In future,synergistic effects of these elements should be more thoroughly investigated.For other nutritional elements,such as Fe and Ca,refining second phase is a matter of vital concern. 展开更多
关键词 Biodegradable Zn alloys Alloy design second phase Microstructure Comprehensive properties
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Enhanced Damping Capacities of Mg–Ce Alloy by the Special Microstructure with Parallel Second Phase 被引量:4
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作者 Zhongshan Wu Jingfeng Wang +4 位作者 Haibo Wang She Ma Song Huang Shun Li Fusheng Pan 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2017年第9期941-946,共6页
Microstructure evolution and damping capacities of Mg–Ce binary alloys with three different Ce contents(0.5, 1, or 2 wt%) have been systematically investigated in this work. Numerous fine parallel second phases in... Microstructure evolution and damping capacities of Mg–Ce binary alloys with three different Ce contents(0.5, 1, or 2 wt%) have been systematically investigated in this work. Numerous fine parallel second phases in Mg–2Ce alloy are obtained, as well as a large number of dislocations around them, but few dislocations appear around the reticular second phase in the Mg–1Ce alloy. Among the three alloys, two internal friction peaks(P;and P;) are detected at about 78 and 167?C in both the Mg–0.5Ce and Mg–1Ce alloys.In addition, the alloy with special parallel second phase structure exhibits excellent damping capacity in both strain amplitude and temperature-dependent regions. These results may be ascribed to the stress concentration and the formation of abundant parallel and uniform dislocation configurations in the ?-Mg matrix without the influence of crystal orientation. The obtained results may provide a novel idea to prepare high-damping magnesium alloys by tailoring their microstructure. 展开更多
关键词 Mg–Ce alloy Parallel second phase Dislocation configuration Damping capacity
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Kinetics of Precipitation Behavior of Second Phase Particles in Ferritic Ti-Mo Microalloyed Steel 被引量:2
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作者 HU Bin-hao CAI Qing-wu WU Hui-bin 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2013年第7期69-77,共9页
Two types of stress relaxation tests were carried out to investigate the incubation time for incipient precipi-tation of Ti(C,N) in deformed austenite and (Ti,Mo)C in ferrite of ferritic Ti-Mo microalloyed steel T... Two types of stress relaxation tests were carried out to investigate the incubation time for incipient precipi-tation of Ti(C,N) in deformed austenite and (Ti,Mo)C in ferrite of ferritic Ti-Mo microalloyed steel The size dis-tribution, amount and chemical composition of precipitates were obtained by using physicochemical phase analysis, and calculated according to thermodynamics and kinetics. The experimental results demonstrated that the incubation time was reduced with increasing Ti content, and prolonged with the addition of Mo. After 30 % deformation at 850 ℃, the nucleation of strain-induced Ti(C,N) was a relatively slow process. On the other hand, the temperature where the nucleation rate of (Ti, Mo)C in ferrite was the highest descended first and then ascended with increasing Ti content, and so did the temperature where the incubation time was the shortest. The key point is that the tempera-ture of steel containing about 0.09 % Ti is the lowest. The mass fraction of MC-type particles with size smaller than 10 nm in steel containing 0.09% Ti and 0.2% Mo reached 73.7%. The size distributions of precipitates in steel containing 0.09% Ti were relatively concentrated compared with that in steel containing 0.07% Ti. 展开更多
关键词 ferritic Ti-Mo microalloyed steel precipitation behavior second phase particle stress relaxation parti-cle size distribution
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Monte Carlo study on abnormal growth of Goss grains in Fe-3%Si steel induced by second-phase particles 被引量:1
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作者 Dong-qun Xin Cheng-xu He +5 位作者 Xue-hai Gong Hao Wang Li Meng Guang Ma Peng-fei Hou Wen-kang Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2016年第12期1397-1403,共7页
The selective abnormal growth of Goss grains in magnetic sheets of Fe-3%Si (grade Hi-B) induced by second-phase particles (AlN and MnS) was studied using a modified Monte Carlo Ports model. The starting microstruc... The selective abnormal growth of Goss grains in magnetic sheets of Fe-3%Si (grade Hi-B) induced by second-phase particles (AlN and MnS) was studied using a modified Monte Carlo Ports model. The starting microstructures for the simulations were generated from electron backscatter diffraction (EBSD) orientation imaging maps of recrystallized samples. In the simulation, second-phase particles were assumed to be randomly distributed in the initial microstructures and the Zener drag effect of particles on Goss grain boundaries was assumed to be selectively invalid because of the unique properties of Goss grain boundaries. The simulation results suggest that normal growth of the matrix grains stagnates because of the pinning effect of particles on their boundaries. During the onset of abnormal grain growth, some Goss grains with concave boundaries in the initial microstructure grow fast abnormally and other Goss grains with convex boundaries shrink and eventually disappear. 展开更多
关键词 silicon steel grain growth second phase particles Monte Carlo simulation
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Drag Effects of Solute and Second Phase Distributions on the Grain Growth Kinetics of Pre-Extruded Mg-6Zn Alloy
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作者 Zhaoyang Jin Donghua Yu +2 位作者 Xintong Wu Kai Yin Kai Yan 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2016年第12期1260-1266,共7页
In order to control the grain size during hot forming,grain growth behavior of a pre-extruded Mg-6Zn magnesium alloy and its correlation with solute and second phase distribution were investigated.Isothermal annealing... In order to control the grain size during hot forming,grain growth behavior of a pre-extruded Mg-6Zn magnesium alloy and its correlation with solute and second phase distribution were investigated.Isothermal annealing was conducted on a Gleeble-1500 thermo-mechanical simulator.The mean grain size Dg of each annealed specimen was measured by the quantitative metallography technique.The grain growth kinetics of the Mg-6Zn alloy annealed at 473-623 K was obtained as Dg^4- Dg0^4=2.25 ×10^11 exp(-95450)by the least square linear regression method.The deviation of grain growth exponent n = 4 from the theoretical value of 2 may be attributed to the presence of solute zinc and second phases which will retard the boundary migration.Microscopic observations show that the non-uniform distribution of grain size for samples pre-extruded or annealed at low temperatures is closely related to the non-uniform distribution of fine and dispersed second phases but not to the non-uniform distribution of solute zinc.This indicates that second phase pinning effect plays an important role in microstructure refinement. 展开更多
关键词 Grain growth kinetics second phase distribution Solute dragging Magnesium alloys
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Interface conjunction factors of the second phase particles in alloys and their effects 被引量:3
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作者 李志林 刘志林 +1 位作者 刘伟东 张凌雯 《Science China(Technological Sciences)》 SCIE EI CAS 2002年第2期195-205,共11页
The second phase in multi-phase alloys has connection with many important phenomena such as aging strengthening,dispersion strengthening,secondary hardening,crystal refinement.In this paper,the interface conjunction f... The second phase in multi-phase alloys has connection with many important phenomena such as aging strengthening,dispersion strengthening,secondary hardening,crystal refinement.In this paper,the interface conjunction factors of the interface between MC(M=V,Nb,Ti) and austenite and martensite are calculate out.The relationship between these factors and the characteristics are analyzed.The reason for the second phases being fine and dispersing and their strengthening and toughening effect on the alloy is explained using the relationship.Based on the relationship,the valence electron structure of the interface between the second phase particles and the matrix can be optimized by changing the alloying elements,which make it possible to design the composition of alloys from the valence electron structure of the second phase particles. 展开更多
关键词 INTERFACE CONJUNCTION factor second phase particle valence electron structure refinement strength-toughness.
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Electrochemical Properties of LiV_3O_8 Containing Dispersed Second Phase 被引量:1
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作者 G.J. WANG G.Y. SU Y.P. WU 《复旦学报(自然科学版)》 CAS CSCD 北大核心 2005年第5期885-886,共2页
关键词 LiV308 锂电池 电解液 电化学 分散相 阴极
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DISLOCATION DISTRIBUTION IN PLASTIC ZONE AT A CRACK TIP WHILE THE HARD SECOND PHASE EXISTS
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作者 高飞 张宏图 《Chinese Science Bulletin》 SCIE EI CAS 1989年第16期1396-1400,共5页
Recent observations by electron microscopy have shown that a dislocation-free zone (DFZ) exists between the crack tip and the pile-up of dislocations in the plastic zone. Shang, S. J., Ohr, S. M. and Majumdar, B. S., ... Recent observations by electron microscopy have shown that a dislocation-free zone (DFZ) exists between the crack tip and the pile-up of dislocations in the plastic zone. Shang, S. J., Ohr, S. M. and Majumdar, B. S., Burns, S. J. have discussed the problem of the plastic zone at a crack tip in isotropic elastic medium. We know that the hard second phase, which neither causes very large stress concentration nor leads to micrographic split, can improve the bearing capacity of the materials. Therefore, it is necessary to discuss the problem of the plastic zone at a crack tip while the hard second phase exists. 展开更多
关键词 HARD second phase CRACK TIP plastic zone DISLOCATION distribution
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Grain growth in a nanostructured AZ31 Mg alloy containing second phase particles studied by phase field simulations
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作者 吴艳 宗亚平 金剑锋 《Science China Materials》 SCIE EI CSCD 2016年第5期355-362,共8页
Phase field models were established to simulate the grain growth of a nanostructured AZ31 magnesium alloy,which contain spherical particles of differing sizes and volume fractions, under realistic spatial and temporal... Phase field models were established to simulate the grain growth of a nanostructured AZ31 magnesium alloy,which contain spherical particles of differing sizes and volume fractions, under realistic spatial and temporal scales.The effect of the second phase particles on the nanostructure evolution was studied. The simulated results were compared with those of the conventional microstructured alloy.The expression of the local free energy density was improved by adding a second phase particle term. The right input parameters were selected for proper physical meaning. It was shown that the rules that govern the pinning effect of the second phase particles during the grain growth were different for the nanostructure and microstructure. There was a critical particle size value that affected the grain growth within the nanostructure. If the particle size was lower than the critical value, the pinning effect on grain growth increased with decreasing particle size. When the particle size was greater than the critical value, the particles had almost no pinning effect.However, in the conventional microstructured material,the larger particle size resulted in an enhanced pinning effect during grain growth for particle sizes smaller than 1 μm. The effect was reversed when the particle size was larger than the critical value. For the nanostructure, the critical value was200 nm when the particle content was 10 v.%, and the critical value decreased when the content increased. When the particle size was 30 nm, the particle pinning effect on the grain growth increased for increasing particle content. 展开更多
关键词 phase field models second phase particles grain growth magnesium alloy
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