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Microstructure of partially remelted billet of AM60 alloy prepared with self-inoculation method 被引量:4
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作者 邢博 李元东 +2 位作者 马颖 陈体军 郝远 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第9期1622-1629,共8页
The billets of AM60 alloy, prepared with self-inoculation method, were partially remelted into semisolid state. Effects of process parameters on remelting microstructure of semisolid billet were investigated. Experime... The billets of AM60 alloy, prepared with self-inoculation method, were partially remelted into semisolid state. Effects of process parameters on remelting microstructure of semisolid billet were investigated. Experimental results show that the solid particles obtained with self-inoculation method are in smaller grain size and globular shape after partial remelting, compared with those prepared with other casting methods. In the optimized process conditions, the average size of solid particles of partially remelted billet is 65 μm, and the shape factor is 1.12. The process parameters, i.e. pouting temperature, addition amount of self-inoculants, and the slope angle of multi-stream mixing cooling chalmel have influence on the microstructure of partially remelted billet. The optimized temperature is from 680 ℃ to 700 ℃, addition amount of self-inoculants is between 5% and 7% (mass fraction), slope angle of multi-stream mixing cooling channel is between 30° and 45°, with which the dendritic microstructure of as-cast billet can be avoided, and the size of solid particles ofremelted billet is reduced. 展开更多
关键词 am60 alloy self-inoculation method semisolid process partial remelting process parameters
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Effects of novel self-inoculation method on microstructure of AM60 alloy 被引量:4
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作者 Xing Bo Li Yuandong +1 位作者 Ma Ying Hao Yuan 《China Foundry》 SCIE CAS 2011年第1期121-126,共6页
A novel cast processing method,self-inoculation method (SIM),was proposed.The process involves the addition of self-inoculant to melt,then pouring the melt to a mould through a multi-stream mixing cooling channel.In t... A novel cast processing method,self-inoculation method (SIM),was proposed.The process involves the addition of self-inoculant to melt,then pouring the melt to a mould through a multi-stream mixing cooling channel.In this paper,the process parameters were investigated.Results indicate that the melt treatment temperature,the amount of self-inoculant added,and the slope angle of the cooling channel are the key factors for SIM process.The optimized parameters are that the melt treatment temperature is between 680 and 700°C;the addition of self-inoculant is between 5wt.% and 7wt.%;and the slope angle of the cooling channel is between 30° and 45°.Further analysis reveals that SIM changes the solidification microstructure of slurry by controlling the nucleation and growth of the primary phase in the melt. 展开更多
关键词 am60 alloy self-inoculation method multi-stream mixing cooling channel nucleation and growth
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Commercial AM60 alloy for semisolid processing:Alloy optimization and thermodynamic analysis 被引量:1
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作者 李元东 D.APELIAN +2 位作者 邢博 马颖 郝远 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第9期1572-1578,共7页
Semisolid processing is now a commercially successful manufacturing route to produce net-shape parts in automotive industry. The conspicuous results of alloy optimization with thermodynamic simulations for semisolid p... Semisolid processing is now a commercially successful manufacturing route to produce net-shape parts in automotive industry. The conspicuous results of alloy optimization with thermodynamic simulations for semisolid processing of commercial AM60 alloy were present. The results indicate that the available processing temperature range of AM60 alloy is 170 ℃. The temperature sensitivity of solid fraction decreases with increasing solid fraction or with decreasing temperature above eutectic reaction temperature of AM60 alloy. When the solid fraction φs is 0.4, corresponding processing temperature is 603.8 ℃ and the sensitivity -dφs/dT is 0.0184. The effects of various alloying elements on the solidification behavior and SSM processability of AM60 alloy were calculated with Pandat software. 展开更多
关键词 am60 alloy semisolid processing alloy optimization thermodynamic analysis solid fraction
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Grain refining technique of AM60B magnesium alloy by MgCO_3 被引量:3
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作者 陈体军 王瑞权 +2 位作者 黄海军 马颖 郝远 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第7期1533-1539,共7页
The effects of grain refining parameters on microstructure of AM60B magnesium alloy with MgCO3 were investigated and then a refining technique was developed.Simultaneously,the corresponding mechanisms were discussed.T... The effects of grain refining parameters on microstructure of AM60B magnesium alloy with MgCO3 were investigated and then a refining technique was developed.Simultaneously,the corresponding mechanisms were discussed.The results indicate that increasing addition temperature of MgCO3 or pouring temperature is beneficial for obtaining fine grains.There is an optimal addition amount of 1.2%at the addition temperature of 790°C.Prolonging holding time at 790°C will increase grain size.The grain refining technique that 1.2%MgCO3 is added at 790°C followed by holding for 10 min and pouring can decrease the grain size from 348μm of the un-refined alloy to 69μm.The nucleation substrates are actually the Al4C3 particles formed from reactions between the MgCO3 and alloying elements in the melt.Besides the heterogeneous nucleation regime,growth restriction of the Al4C3 particles agglomerated at growing front is the other mechanism. 展开更多
关键词 am60B magnesium alloy grain refinement MGCO3
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Effects of shot speed and biscuit thickness on externaly solidified crystals of high-pressure diet cast AM60B magnesium alloy 被引量:4
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作者 王柏树 熊守美 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第4期767-772,共6页
Standard mechanical test bars with a diameter of 6.4 mm and a gauge length of 50 mm were processed, and the microstructures of die cast AM60B alloy under different die casting process parameters were observed. The inf... Standard mechanical test bars with a diameter of 6.4 mm and a gauge length of 50 mm were processed, and the microstructures of die cast AM60B alloy under different die casting process parameters were observed. The influences of the slow shot speed, the fast shot speed and the biscuit thickness on the externally solidified crystals (ESCs) were investigated. With the increase of the biscuit thickness, the number of the ESCs in the cast samples decreases. Under a low slow shot speed, larg ESCs are found in the cast structure and a high fast shot speed results in more spherical ESCs. The relationships between ESCs and process parameters were also discussed. 展开更多
关键词 am60B magnesium alloy die casting microstructure externally solidified crystals
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Properties inhomogeneity of AM60 magnesium alloy processed by cyclic extrusion compression angular pressing followed by extrusion 被引量:9
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作者 Siroos AHMADI Vali ALIMIRZALOO +1 位作者 Ghader FARAJI Ali DONIAVI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第3期655-665,共11页
A new severe plastic deformation(SPD)technique for improvement of the metallurgical properties of the magnesium alloys is presented.In this process,a cyclic extrusion compression angular pressing(CECAP)process is foll... A new severe plastic deformation(SPD)technique for improvement of the metallurgical properties of the magnesium alloys is presented.In this process,a cyclic extrusion compression angular pressing(CECAP)process is followed by an extrusion step in the outlet playing the role of additional back pressure.Therefore,more uniform and enhanced mechanical properties are expected in comparison with equal channel angular pressing(ECAP).In order to evaluate the effectiveness and capabilities of this new method,an AM60 magnesium alloy was processed.Finite element results exhibited a significant increase in strain values as well as uniform strain distribution for the new method.In addition,~110%increase in compressive stress was observed in new method compared to the conventional ECAP.Experimental results revealed a noticeable increase in the hardness and strength of the specimens processed by the new technique as a result of the formation of finer grains and more homogeneous microstructure with good distribution of refinedβ-phase along the boundaries.It may be concluded that the new process is very promising for future magnesium alloy products. 展开更多
关键词 cyclic extrusion compression angular pressing am60 alloy strain distribution mechanical properties grain refinement
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Microstructural evolution during solution treatment of thixoformed AM60B Mg alloy 被引量:1
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作者 黄海军 陈体军 +1 位作者 马颖 郝远 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第4期745-753,共9页
The microstructural evolution and kinetic characteristics were studied during solution treatment of AM60B Mg alloy prepared by thixoforming. The results indicate that the microstructural evolution includes two stages... The microstructural evolution and kinetic characteristics were studied during solution treatment of AM60B Mg alloy prepared by thixoforming. The results indicate that the microstructural evolution includes two stages: the first stage involves rapid dissolution of eutectic β (Mg 17 Al 12 ) phase, homogenization and coarsening, and the second stage is regarded as normal grain growth consisting of primary α-Mg particles (primary particles) and secondary α-Mg grains (secondary grains). In the first stage, the dissolution completes in a quite short time because the fine β phase can quickly dissolve into the small-sized secondary grains. The homogenization of Al element needs relatively long time. Simultaneously, the microstructure morphology and average grain size obviously change. The first stage sustains approximately 1 h when it is solutionized at 395 ℃ Comparatively, the second stage needs very long time and the microstructure evolves quite slowly as a result of low Al content gradient and thus low diffusivity of Al element after the homogenization of the first stage. The growth model of primary particles obeys power function while that of the secondary grains follows the traditional growth equation in the first stage. In the second stage, both of the primary particles and secondary grains behave a same model controlled by diffusion along grain boundaries and through crystal lattice. 展开更多
关键词 am60B Mg alloy THIXOFORMING solution heat treatment microstructure kinetics
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Microstructural evolution during partial remelting of AM60B magnesium alloy refined by MgCO_3 被引量:4
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作者 陈体军 马颖 +2 位作者 王瑞全 李元东 郝远 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第9期1615-1621,共7页
AM60B magnesium alloy was refined by MgCO3 and its microstmcturat evolution was investigated during partial remelting. The results indicate that MgCO3 is an effective grain refiner for AM60B alloy and can decrease the... AM60B magnesium alloy was refined by MgCO3 and its microstmcturat evolution was investigated during partial remelting. The results indicate that MgCO3 is an effective grain refiner for AM60B alloy and can decrease the grain size from 329 pm of the unrefined alloy to 69 μm. A semisolid microstructure with small and spheroidal primary particles can be obtained after being partially remelted. The microstructure evolution can be divided into four steps: the initial rapid coarsening, structure separation, spheroidization and final coarsening. Correspondingly, these four steps result from the phase transformations of β→α, α+β→L and α→L, α→L and two reverse reactions of α→L and L→α, respectively. One spheroidal primary particle in the semisolid microstmcture usually originates one dendrite in the as-cast microstructure. The variation of primary particle size with holding time does not obey the LSW law, Dt^3-Do^3=Kt, after the semisolid system is in its solid-liquid equilibrium state. Longer heating duration makes the primary particles more globular, but it makes their size larger at the same time. 展开更多
关键词 am60B alloy THIXOFORMING microstructure evolution phase transformation partial remelting
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Weibull analysis of effect of T6 heat treatment on fracture strength of AM60B magnesium alloy 被引量:2
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作者 A.H.SHEVIDI R.TAGHIABADI A.RAZAGHIAN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第1期20-29,共10页
The effect of T6heat treatment on the fracture strength and reliability of AM60B alloy was studied.The tensile specimens were poured at three different temperatures of670,685and700?C for different holding times of5,10... The effect of T6heat treatment on the fracture strength and reliability of AM60B alloy was studied.The tensile specimens were poured at three different temperatures of670,685and700?C for different holding times of5,10and15min.The fluidity test was also conducted to determine the fluidity length under different pouring temperatures and holding times.According to the results,the optimum pouring temperature and holding time were determined as685?C and10min,respectively.SEM fractography of the tensile specimens reveals that the entrained oxides and oxide-related porosities are the main factors responsible for the reduction of fracture strength under the non-optimal casting conditions.The Weibull statistical approach was used to quantify the scatter of fracture strength in as-cast and heat-treated conditions.For this purpose,T6schedule was applied to the specimens prepared under the optimal casting condition.It is found that,despite minor effect on the average fracture strength,T6heat treatment improves the reliability of castings,where the Weibull modulus is increased by75%.According to the microstructural and fractography observations,this improvement is related to the evolution of more uniform microstructure and the elimination of coarse brittleβ-particles in heat-treated samples. 展开更多
关键词 Mg.Al alloy am60B alloy DIE-CAST Weibull analysis fracture strength FLUIDITY
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Influence of Sn addition on mechanical properties of gas tungsten arc welded AM60 Mg alloy sheets 被引量:2
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作者 Jun GOU Ai-tao TANG +4 位作者 Fu-sheng PAN Jia SHE Su-qin LUO Jun-hua YE Da-wei SHI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第8期2051-2057,共7页
The effects of Sn addition on the microstructure and mechanical properties of gas tungsten arc butt-welded Mg?6Al?0.3Mn (AM60) (mass fraction, %) alloy sheets were investigated by optical microscopy, scanning electron... The effects of Sn addition on the microstructure and mechanical properties of gas tungsten arc butt-welded Mg?6Al?0.3Mn (AM60) (mass fraction, %) alloy sheets were investigated by optical microscopy, scanning electron microscopy, X-ray diffraction, transmission electron microscopy, and microhardness and tensile tests. The results indicate that both the average microhardness and joint efficiency of AM60 are improved by the addition of 1% Sn (mass fraction). The ultimate tensile strength of Mg?6Al?1Sn?0.3Mn (ATM610) reaches up to 96.8% of that of base material. Moreover, fracture occurs in the fusion zone ofATM610 instead of in the heat-affected zone of AM60 welded joint. The improvement in the properties is mainly attributed to the formation of Mg2Sn, which effectively obstructs the grain coarsening in the heat-affected zone, resulting in a relatively finemicrostructure. The addition of 1% Sn improves the mechanical properties of AM60 welded joint 展开更多
关键词 am60 Mg alloy ATM610 Mg alloy gas tungsten arc welding mechanical properties
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Design of experiment study on hardness variations in friction stir welding of AM60 Mg alloy 被引量:2
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作者 S.Richmire K.Hall M.Haghshenas 《Journal of Magnesium and Alloys》 SCIE EI CAS 2018年第3期215-228,共14页
Identification of process parameters,their effects and contributions to the outcomes of the system using experimental approach could be a daunting,time consuming,and costly course.Using proper statistical methods,i.e.... Identification of process parameters,their effects and contributions to the outcomes of the system using experimental approach could be a daunting,time consuming,and costly course.Using proper statistical methods,i.e.,Taguchi method,could significantly reduce the number of required experiments and statistical significance of the parameter can be identified.Friction stir welding is one of those welding techniques with many parameters which have different effects on the quality of the welds.In friction stir welding the tool rotational speed(RPM)and transverse speed(mm/min)influence the strength(i.e.,hardness distribution)of the stirred zone.In this study,these two factors are investigated to determine the effect they will have on the hardness in the stirred zone of the friction stir welds and how the two factors are related to one another for as-cast magnesium alloy AM60 with nominal chemical composition of Mg-(5.5-6.5)Al-(0.24-0.6)Mn-0.22Zn-0.1Si.Experimental data was taken at three different tool rotational speeds and three different transverse speeds.The data obtained was then analyzed using a 32 factorial design to find the contribution of these parameters.It was determined that both tool rotational speed and transverse speed possess significant effects on the stir zone hardness.Also,the interactions between the two factors were statistically assessed. 展开更多
关键词 am60 Mg alloy Design of experiment(DOE) Statistical method Friction stir welding
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Grain refining technique of AM60B alloy by Al-Ti-B master alloy 被引量:2
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作者 Chen Tijun Wang Ruiquan +1 位作者 Ma Ying Hao Yuan 《China Foundry》 SCIE CAS 2011年第4期380-385,共6页
The effects of grain refining parameters on grain size of AM60B magnesium alloy have been investigated using an Al-5Ti-IB master alloy as refiner; and an appropriate refining technique has been developed. The results ... The effects of grain refining parameters on grain size of AM60B magnesium alloy have been investigated using an Al-5Ti-IB master alloy as refiner; and an appropriate refining technique has been developed. The results indicate that the Al-Ti-B master alloy is an effective grain refiner for AM60B alloy and the grain size can be decreased from 348 μm to 76 μm. Raising the addition temperature or the poudng temperature is beneficial for grain refinement; while for the addition amount and holding time, there is an optimal value. The appropriate grain refining technique is that 0.3% Al-Ti-B master alloy is added at 780℃ and then the melt is held for 30 min before pouring. The above phenomena can be explained by the refining mechanisms that have been proposed from the related studies on Al and Mg alloys and theoretical analysis. 展开更多
关键词 am60B magnesium alloy grain refinement Al-Ti-B master alloy refining mechanism
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Effect of rare earth elements on the microstructure and property for magnesium alloy AM60B 被引量:3
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作者 KaikunWang KuiZhang 《Journal of University of Science and Technology Beijing》 CSCD 2002年第6期466-469,共4页
The effects of rare earth elements on the microstructure and properties ofmagnesium alloy AM60B alloy were studied. Different proportions of rare earth elements were added toAM60B and the tensile tests were carried ou... The effects of rare earth elements on the microstructure and properties ofmagnesium alloy AM60B alloy were studied. Different proportions of rare earth elements were added toAM60B and the tensile tests were carried out under different temperatures. The experimental resultsshow that at room temperature the tensile strength of AM60B can be improved with the addition ofrare earth elements. The ductility of which at room or elevated temperature (120 deg C) can also beimproved, and the ductility is to some extent in proportion with the amount of rare earth elements.The ductility at 120 deg C is better than that at room temperature. The microstructure graphsdemonstrate that appropriate amount of rare earth elements (0.1 percent-0.2 percent, mass fraction)can fine AM60B's grain and improve its ductility. 展开更多
关键词 magnesium alloy am60B rare earth elements STRENGTH DUCTILITY MICROSTRUCTURE
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Equal Channel Angular Deformation (ECAD) of As-Cast AM60 Magnesium Alloy
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作者 PengLUO XiaolinWU KenongXIA 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2003年第6期513-515,共3页
As-cast AM60 magnesium alloy ingot with grains coarser than those of as-extruded AZ series is more liable to produce cracks under ECAD with severe shear strain. A feasible scheme of equal channel angular deformation (... As-cast AM60 magnesium alloy ingot with grains coarser than those of as-extruded AZ series is more liable to produce cracks under ECAD with severe shear strain. A feasible scheme of equal channel angular deformation (ECAD) for as-cast AM60 magnesium alloy ingot was proposed in this paper. The tests were conducted on Instron machine with hydraulic back-force machine. Through analysing load us displacement curves, the effects of ECAD processing conditions on deformability and microstructure of as-cast magnesium AM60 billets were discussed. During testing, the back-force employment was helpful to keep ECAD processing more stable. And with back-force, it was observed that the number of ECAD passes in different routes could tremendously affect the deformability and microstructure of magnesium specimens. It was concluded that ECAD processing is entirely feasible for as-cast magnesium AM60 alloy under severe shear strain, and back-force employment, multi-passes deformation and lubrication of graphite paper are the factors primarily beneficial to improvement of deformability and refinement of grained structure. This work provides a way to produce magnesium alloy with fine-grained structure directly from casting ingot by ECAD technique. 展开更多
关键词 ECAD am60 magnesium alloy DEFORMABILITY METALLOGRAPHY
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Section thickness-dependent tensile properties of squeeze cast magnesium alloy AM60
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作者 Xuezhi Zhang Meng Wang Zhizhong Sun Henry Hu 《China Foundry》 SCIE CAS 2012年第2期178-183,共6页
The development of alternative casting processes is essential for the high demand of light weight magnesium components to be used in the automotive industry, which often contain different section thicknesses. Squeeze ... The development of alternative casting processes is essential for the high demand of light weight magnesium components to be used in the automotive industry, which often contain different section thicknesses. Squeeze casting with its inherent advantages has been approved for the capability of minimizing the gas porosity in magnesium alloys. For advanced engineering design of light magnesium automotive applications, it is critical to understand the effect of section thickness on mechanical properties of squeeze cast magnesium alloys. In this study, magnesium alloy AM60 with different section thicknesses of 6, 10 and 20 mm squeeze cast under an applied pressure of 30 MPa was investigated. The prepared squeeze cast AM60 specimens were tensile tested at room termperature. The results indicate that the mechanical properties including yield strength (YS), ultimate tensile strength (UTS) and elongation (A) decrease with an increase in section thickness of squeeze cast AM6O. The microstructure analysis shows that the improvement in the tensile behavior of squeeze cast AM60 is primarily attributed to the low-gas porosity level and fine grain strucuture which result from the variation of cooling rate of different section thickness. The numerical simulation (Magmasoft) was employed to determine the solidification rates of each step, and the simulated results show that the solidification rate of the alloy decreases with an increase in the section thickness. The computed solidification rates support the experimental observation on grain structural development. 展开更多
关键词 squeeze casting magnesium alloy am60 tensile properties section thickness
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Correlation between Porosity and Fracture Mechanism in High Pressure Die Casting of AM60B Alloy 被引量:27
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作者 X.Li S.M.Xiong Z.Guo 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2016年第1期54-61,共8页
X-ray tomography was used to characterize the porosity in high pressure die casting of AM60B alloy. In situ tensile deformation was performed to observe the change of porosities and their influences on crack initiatio... X-ray tomography was used to characterize the porosity in high pressure die casting of AM60B alloy. In situ tensile deformation was performed to observe the change of porosities and their influences on crack initiation, propagation and subsequent fracture of specimen. Results showed that four types of porosi- ties, including gas-shrinkage pore, gas pore, net-shrinkage and island-shrinkage, could be identified according to the formation mechanism and morphology characterization. During tensile deformation, it was shown that the gas-shrinkage pore and net-shrinkage, rather than gas pore or island-shrinkage, were the main sources for crack initiation. In addition, the crack propagated by interconnecting the po- rosities at the cross section with minimum efficient force bearing area. At these locations where externally solidified crystals (ESCs) were present, the crack would propagate along the ESC boundaries in an inter- granular mode, while at these locations without ESCs, the crack would propagate roughly along the direction perpendicular to the tensile stress in a combination of trans-granular and inter-granular modes. 展开更多
关键词 High pressures die casting am60B alloy Fracture mechanism POROSITY
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Characterization of the Grain Structures in Vacuum-Assist HighPressure Die Casting AM60B Alloy 被引量:5
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作者 Xiao-Bo Li Shou-Mei Xiong Zhi-Peng Guo 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2016年第7期619-628,共10页
The structures in vacuum-assist high-pressure die casting (HPDC) AM60B alloy were studied by using an optical microscope and a scanning electron microscope with an energy dispersive spectrometer. It was found that t... The structures in vacuum-assist high-pressure die casting (HPDC) AM60B alloy were studied by using an optical microscope and a scanning electron microscope with an energy dispersive spectrometer. It was found that the HPDC under the vacuum could significantly change the morphology and distribution of the microstructure. For both conventional and vacuum-assist HPDC processes, the externally solidified crystals (ESCs) tended to aggregate in the center along the thickness direction of the castings. Besides, the aggregation was more pronounced, and the number of ESCs decreased, and the ESCs tended to become smaller and more globular, as the distance between the specimen location and runner increased. Compared with the conventional castings, the vacuum-assist HPDC can significantly reduce the size and amount of ESCs, and the ESCs tended to be more globular. For the distribution of ESCs along the thickness of the specimens, the aggregation tendency was more pronounced in vacuum-assist die castings than that in conventional castings. Besides, the distribution of ESCs at different locations was more converged in the vacuum-assist HPDC than that in the conventional HPDC. 展开更多
关键词 am60B alloy Grain structure Vacuum-assist high-pressure die casting Externally solidifiedcrystals
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Microstructure Characteristics of the Eutectics of Die Cast AM60B Magnesium Alloy 被引量:6
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作者 MengwuWu Shoumei Xiong 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2011年第12期1150-1156,共7页
Under the cold-chamber high pressure die casting (HPDC) process, samples were produced with AM60B magnesium alloy to investigate the microstructure characteristics of the eutectics, especially focusing on the consti... Under the cold-chamber high pressure die casting (HPDC) process, samples were produced with AM60B magnesium alloy to investigate the microstructure characteristics of the eutectics, especially focusing on the constitution, morphology and distribution of the eutectics over cross section of the castings. Attentions were also paid to study the effect of heat treatment on the eutectics in the die castings. Based on experimental analysis using optical microscopy (OM), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS), it was determined that fully divorced eutectics consisting of c^-Mg and l%MglzA112 appeared at the grain boundary of the primary c^-Mg in the as-cast microstructure. Islands and networks of β-Mg17Al12 phase were observed in the central region of the castings, while the β-Mg17Al12 phase revealed a more dispersed and granular morphology on the surface layer. The two phases ratio β/α in the central region of the castings was approximately 10%, which was higher than that on the surface layer. Besides, the defect bands contained a higher percentage of the eutectics than the adjacent regions. After aging treatment (T6), only α-Mg phase was detected by XRD in the AM60B magnesium alloy, though a small amount of precipitated β-MgITAI12 phase was observed at the grain boundary. In contrast to the microstructure of die cast AZ91D magnesium alloy under the same T0 heat treatment, no discontinuous precipitation of the β-MgITAI12 phase was observed in AMO0B magnesium alloy die castings. 展开更多
关键词 am60B magnesium alloy High pressure die casting Fully divorced eutectic Heat treatment
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