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| 1 | Effects of Ce and Sb on the microstructure and properties of AZ91D magnesium alloy prepared by the EPC process显示文摘The effects of small amounts of cerium and antimony additions on the microstructure and the mechanical properties of AZ91D(Mg-9Al-Zn) based alloy were researched via the expendable pattern casting(EPC) process.The results show that the microstructure is obviously refined and the tensile strength of the AZ91D based alloy at ambient temperature is significantly improved.When compared to AZ91D,the AZ91D-1.0%Ce-0.4%Sb alloy has higher ultimate tensile strength and elongation.Its ultimate tensile strength and elongation are enhanced by 39% and 47%,respectively.The morphology of the tensile fracture of the AZ91D-1.0%Ce-0.4%Sb alloy has more characteristics of quasi-cleavage.This indicates that it has had a larger plastic deformation before failure.The tensile strength and elongation decrease with the increase of Ce and Sb contents because of the coarsening and volume increase of CeSb and Al11Ce3 phases. | LI Jiqiang DONG Xuanpu FAN Zitian WANG Yuanqing | 2008 | Rare Metals2008，27，1： | 19 |
| 2 | Gating system optimization of low pressure casting A356 aluminum alloy intake manifold based on numerical simulation显示文摘To eliminate the shrinkage porosity in low pressure casting of an A356 aluminum alloy intake manifold casting, numerical simulation on fi lling and solidifi cation processes of the casting was carried out using the ProCAST software. The gating system of the casting is optimized according to the simulation results. Results show that when the gating system consists of only one sprue, the fi lling of the molten metal is not stable; and the casting does not follow the sequence solidifi cation, and many shrinkage porosities are observed through the casting. After the gating system is improved by adding one runner and two in-gates, the fi lling time is prolonged from 4.0 s to 4.5 s, the fi lling of molten metal becomes stable, but this casting does not follow the sequence solidifi cation either. Some shrinkage porosity is also observed in the hot spots of the casting. When the gating system was further improved by adding risers and chill to the hot spots of the casting, the shrinkage porosity defects were eliminated completely. Finally, by using the optimized gating system the A356 aluminum alloy intake manifold casting with integrated shape and smooth surface as well as dense microstructure was successfully produced. | Jiang Wenming Fan Zitian | 2014 | China Foundry2014，11，2： | 14 |
| 3 | Influence of mechanical vibration on the solidification of a lost foam cast 356 alloy显示文摘Mechanical vibration was applied to the solidification of a lost foam cast(LFC) 356 aluminum alloy.Effects of mechanical vibration,with different peak acceleration,on the size and morphology of α-Al phase,and also on the mechanical properties of the castings were studied.Results indicated that α-Al dendrites gradually grow into equiaxed grains as the peak acceleration of vibration is increased.When the peak acceleration is between about 1 to 4 g,α-Al phase distribution is uniform and is refined obviously.α-Al dendrites are reduced and the mechanical properties of the castings are improved significantly when compared to those of the castings that are produced without vibration.However,when the peak acceleration is higher than 4 g,strong vibration will lead to defects formation,such as sand adhesion,while the amount and size of pores will be increased.And due to the turbulent flow that caused by strong vibration,the chance of forming large pores in the matrix has been increased significantly.The increase in defects will result in the deterioration of mechanical properties. | Zhao Zhong Fan Zitian Dong Xuanpu Tang Bo Pan Di Li Jiqiang | 2010 | China Foundry2010，7，1： | 7 |
| 4 | Status quo and development trend of lost foam casting technology显示文摘Lost foam casting(LFC)technology has been widely applied to cast iron and cast steel.However,the development of LFC for Al and Mg alloys was relatively slower than that for cast iron and cast steel.The application of LFC to Al and Mg alloys needs more effort,especially in China.In this paper,the development history of LFC is reviewed,and the application situations of LFC to Al and Mg alloys are mainly discussed.Meanwhile,the key problems of LFC for Al and Mg alloys are also pointed out.Finally,the prospects for LFC technology are discussed,and some special new LFC technologies are introduced for casting Al and Mg alloys.In future,the development trends of green LFC technology mainly focus on the special new LFC methods,metal material,coating,heat treatment,new foam materials as well as purification technology of tail gas,etc. | Fan Zitian Jiang Wenming Liu Fuchu Xiao Botao | 2014 | China Foundry2014，11，4： | 6 |
| 5 | Properties of sodium silicate bonded sand hardened by microwave heating显示文摘The sodium silicate bonded sand hardened by microwave heating has many advantages,such as low sodium silicate adding quantity,fast hardening speed,high room temperature strength,good collapsibility and certain surface stability. However,it has big moisture absorbability in the air,which would lead to the compression strength and the surface stability of the sand molds being sharply reduced. In this study,the moisture absorbability of the sodium silicate bonded sand hardened by microwave heating in different humidity conditions and the effect factors were investigated. Meanwhile,the reasons for the big moisture absorbability of the sand were analyzed. Some measures to overcome the problems of high moisture absorbability,bad surface stability and sharply reducing strength in the air were discussed. The results of this study establish the foundation of green and clean foundry technology based on the microwave heating hardening sodium silicate sand process. | Wang Jina Fan Zitian Zan Xiaolei Pan Di | 2009 | China Foundry2009，6，3： | 6 |
| 6 | Enhanced mechanical properties of 6082 aluminum alloy via SiC addition combined with squeeze casting显示文摘In order to improve mechanical properties of 6082 aluminum alloy,the SiC_(p)/Al 6082 composites were prepared by the addition of the micron-sized SiC_(p)articles combined with the squeeze casting.The effects of the SiC_(p)content and squeeze casting on the microstructure and mechanical properties of the 6082 aluminum alloy were investigated by SEM,EDS,TEM,tensile testing and hardness testing analysis methods.Research results exhibited that the SiC_(p)content and squeeze casting had a significant impact on the microstructure and mechanical properties of the 6082 aluminum alloy.The addition of the SiC_(p)refined the grain size of the 6082 aluminum alloy while caused the increase of the porosity with increasing the SiC_(p)content,especially in the permanent mold casting condition.Compared to the permanent mold casting,the squeeze casting obviously reduced pore defects,refined grain size and made the SiC_(p)distribute evenly as well as bond tightly with the Al matrix.The tensile strength,yield strength,elongation,elastic modulus and hardness of the 6082 aluminum alloy obtained with the SiC_(p)and squeeze casting were remarkably improved,and the optimal mechanical properties were obtained with a 2 wt.%SiC_(p),and they increased 10.73%,72.7%,193.9%,23.5%and 25.2%,respectively,compared to those of the6082 aluminum alloy obtained without SiC_(p)and squeeze casting.The fracture surface of the SiC_(p)/Al 6082 composites obtained with the squeeze casting was dense and exhibited a ductile fracture mode. | Wenming Jiang Junwen Zhu Guangyu Li Feng Guan Yang Yu Zitian Fan | 2021 | Journal of Materials Science & Technology2021，，29： | 6 |
| 7 | Investigating on casting mold (or core) making with coated sand by the selected laser sintering显示文摘1 .Introduction Based on the parameters and cross-section’s information from a CAD model, the selected laser sintering (SLS) uses a laser beam to sinter selectively powdered solid materials (plastic, wax, ceramic, metal, etc.), and the solidified material is built up layer by layer to formthepart needed} As there are still some problems in material and technology, it is difficulty to sinter or produce | ~*Zitian FAN, Naiyu HUANG, Yan LI, Zhili LIU(State Key Laboratory of Plastic Simulation and Die & Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, Hubei, P. R. China) | 2004 | China Foundry2004，1，2： | 6 |
| 8 | Study on typical hole defects in AZ91D magnesium alloy prepared by low pressure lost foam casting显示文摘The hole defects can easily occur in magnesium alloy castings that are prepared by low pressure lost foam casting(LP-LFC)process when the process parameters such as vacuum,pouring temperature and f illing velocity are not properly selected.In this study,the forming mechanism of the hole defects in AZ91D magnesium castings by LP-LFC process was investigated.The shape,location and surface appearance of the hole defects were observed using optical microscopy and scanning electron microscopy,and the chemical composition on the surface of the holes was analyzed using energy spectrometer.The result indicates that there are two types of hole defects,i.e.,the pyrolysis products related hole defects,including concentrative hole and blow hole defects,and slag related hole defects.The concentrative hole and the blow-hole defects were formed either by the liquidEPS degradation products entrapped in the molten metal under the condition that the pouring temperature is equal to or lower than 730℃,or by the hindered transport of EPS pyrolysis products.Some irregular shape hole defects were caused by slag or by coating slough entrapment when the pouring temperature is equal to 750℃and the f illing velocity is equal to or greater than 100 mm·s-1.To reduce or eliminate the hole defects,the vacuum and f illing velocity must be properly chosen to ensure that the metal front prof ile exhibits convex shape and in laminar current state,and the pouring temperature should be just high enough to ensure that the molten melt has adequate heat energy to complete the foam pyrolysis and to fully occupy the mould.For AZ91D magnesium castings in this study,the parameters should be 730℃pouring temperature,0.02-0.03 MPa vacuum and 80mm·s-1f illing velocity. | Li Jiqiang Zhao zhong Fan Zitian Dong Xuanpu Shi Hualiang | 2013 | China Foundry2013，10，4： | 5 |
| 9 | Wet reclamation of sodium silicate used sand and biological treatment of its wastewater by Nitzschia palea显示文摘The massive amount of sodium silicate in the used sand was a pollution source,especially in the waste water from the wet reclamation of used sand.A new process of wet reclamation by biologically treating the waste water produced during the wet reclamation process of used sand was studied in the paper.In the work,the pre-cultivation of N.palea was performed firstly,and three different scrubbing solutions:(1) tap water,(2) modified medium for N.palea,and (3) filtrate of the broth treated by N.palea for 15 days,were used.The results of the primary investigation show that a de-skinning ratio of 90% is obtained when using the scrubbing solution containing modified medium for N.palea at the ratio 1:2 of sand and scrubbing solution,and the maximal concentrations of Na+ and SiO32are 1.49 g·L-1 and 0.51 g·L-1,respectively.The results of the optimal biomass,pH value decrease and Na+ and SiO32consumption indicate the optimal incubation conditions are at the irradiance of 5,000 lux and 25 oC.Using the filtrate of the broth treated by N.palea for 15 days as the scrubbing solution directly,a de-skinning ratio of 93% is the highest compared to the results of the tap water and the modified medium for N.palea.In the biological process using N.palea,less water is used and little wastewater is produced,which is advantageous to the purpose of green manufacturing and environmental protection. | Wang Huafang Fan Zitian Yu Shaoqiang Liu Fuchu Li Xuejie | 2012 | China Foundry2012，9，1： | 5 |
| 10 | A new low-cost method of reclaiming mixed foundry waste sand based on wet-thermal composite reclamation显示文摘A lot of mixed clay-resin waste sand from large-scale iron foundries is discharged every day; so mixed waste sand reclamation in low cost and high quality has a great realistic significance. In the study to investigate the possibility of reusing two types of waste foundry sands, resin bonded sand and clay bonded sand which came from a Chinese casting factory, a new low-cost reclamation method of the mixed foundry waste sand based on the wet-thermal composite reclamation was proposed. The waste resin bonded sand was first reclaimed by a thermal method and the waste clay bonded sand was reclaimed by a wet method. Then, hot thermal reclaimed sand and the dehydrated wet reclaimed sand were mixed in certain proportions so that the hot thermal reclaimed sand dried the wet reclaimed sand leaving some water. The thermal reclamation efficiency of the waste resin bonded sand was researched at different heat levels. The optimized wet reclamation process of the waste clay bonded sand was achieved by investigating the effects of wet reclamation times, sand-water ratio and pH value on the reclaimed sand characteristics. The composite reclamation cost also was calculated. The research results showed that the properties of the mixed reclaimed sand can satisfy the application requirements of foundries; in which the temperature of the thermal reclamation waste resin bonded sand needs to be about 800 oC, the number of cycles of wet reclamation waste clay bonded sand should reach four to five, the optimal sand-water ratio of wet reclamation is around 1:1.5, and the pH value should be adjusted by adding acid. The mass ratio of hot thermal reclaimed sand to dehydrated wet reclaimed sand is about 1:2.5, and the composite reclaimed sand cost is around 100 yuan RMB per ton. | Fan Zitian Liu Fuchu Long Wei Li Guona | 2014 | China Foundry2014，11，5： | 5 |
| 11 | Dry reusing and wet reclaiming of used sodium silicate sand显示文摘Based on the characteristics of used sodium silicate sand and the different use requirements for recycled sand, 'dry reusing and wet reclaiming of used sodium silicate sand' is considered as the most suitable technique for the used sand. When the recycled sand is used as support sand, the used sand is only reused by dry process including breaking, screening, dust-removal, etc., and it is not necessary that the used sand is reclaimed with strongly rubbing and scraping method, but when the recycled sand is used as facing sand (or single sand), the used sand must be reclaimed by wet method for higher removal rate of the residual binders. The characteristics and the properties of the dry reused sand are compared with the wet reclaimed sand after combining the different use requirements of support sand and facing sand (or single sand), and above the most adaptive scheme has also been validated. | Zitian FAN Naiyu HUANG Huafang WANG Xuanpu DONG | 2005 | China Foundry2005，2，1： | 4 |
| 12 | Novel technologies for the lost foam casting process显示文摘 | Wenming JIANG Zitian FAN | 2018 | Frontiers of Mechanical Engineering2018，13，1： | 3 |
| 13 | Research on cracking mechanism of the thin shell mould in expendable pattern shell casting during pattern removal process显示文摘Aiming at the cracking phenomenon of the thin shell mould in the expendable pattern shell casting during the pattern removing process, some systemic researches are presented.The influence of the pattern removing method and temperature on the pattern removing were investigated.The shell mould cracking mechanism was analyzed by using thermo-gravimetric analysis (TGA), and combining the temperature field and the volume change of the expanded polystyrene (EPS) foam pattern being tested.The results indicated that the shell mould was not easily cracked when the pattern removing process was carried out with the furnace being heated little by little because of the shell slowly shrinking with dehydration and shell strength gradually increasing.The shell mould was soon destroyed when it was set directly into the furnace at above 400 oC because of the thin shell mould rapidly shrinking and the foam pattern hindering.However, the shell mould had no cracking when it had been preheated for a long time even if the furnace temperature was above 400 oC and the shell was put into the furnace directly.Moreover, when the shell mould was directly set into the furnace at lower temperatures, 250 to 300 ℃, the shell would shrink slowly and the foam pattern would stay at the maximum expansion stage temperature of 100 to 110 ℃ for a long time; and the shell mould would experience an expansion force from the foam pattern for a long time.The expansion force is related to the pattern removing temperature, holding time, foam pattern thickness and density.Therefore, the foam pattern with higher density could make the shell crack. | Jiang Wenming Fan Zitian Liao Defeng Zhao Zhong | 2010 | China Foundry2010，7，3： | 3 |
| 14 | Accuracy analysis of the part made by selected laser sintering显示文摘The effects of different factors, including the precision of selected laser sintering (SLS) equipment, sintering temperature, sintered thickness of individual layer and laser scanning route, on the SLS part accuracy have been analyzed and studied. Some measures are suggested in order to improve the part accuracy made by SLS. | Zitian FAN Naiyu HUANG Yuejia XIAO Ming HAN | 2004 | China Foundry2004，1，1： | 3 |
| 15 | Study on microstructure and properties of Mg-alloy surface alloying layer fabricated by EPC显示文摘AZ91D surface alloying was investigated through evaporative pattern casting(EPC) technology.Aluminum powder(0.074 to 0.104 mm) was used as the alloying element in the experiment.An alloying coating with excellent properties was fabricated,which mainly consisted of adhesive,co-solvent,suspending agent and other ingredients according to desired proportion.Mg-alloy melt was poured under certain temperature and the degree of negative pressure.The microstructure of the surface layer was examined by means of scanning electron microscopy.It has been found that a large volume fraction of network new phases were formed on the Mg-alloy surface,the thickness of the alloying surface layer increased with the alloying coating increasing from 0.3 mm to 0.5 mm,and the microstructure became compact.Energy dispersive X-ray(EDX) analysis was used to determine the chemical composition of the new phases.It showed that the new phases mainly consist of β-Mg17Al12,in addition to a small quantity of inter-metallic compounds and oxides.A micro-hardness test and a corrosion experiment to simulate the effect of sea water were performed.The result indicated that the highest micro-hardness of the surface reaches three times that of the matrix.The corrosion rate of alloying samples declines to about a fifth of that of the as-cast AZ91D specimen. | Chen Dongfeng Dong Xuanpu Fan Zitian Xu Qian Zhang Xiong | 2010 | China Foundry2010，7，1： | 3 |
| 16 | Effects of rare earth elements addition on microstructures, tensile properties and fractography of A357 alloy显示文摘 | Wenming Jiang Zitian Fan Yucheng Dai Chi Li | 2014 | Materials Science & Engineering A2014，，： | 2 |
| 17 | A Note on the Property of ψ-Function显示文摘About the accurate value of ψ ( x ) = Γ′ ( x ) / Γ ( x), we know only ψ (1)and ψ (1/ 2).In this paper, by calculating the accurate values of some series expansion of a function and applying some skills of complex analysis, we prove that the expression of the ψ-function admits a finite expression in elementary function for rational number z. As an application, some examples are given. | XIE Zitian ZHOU Qinghua | 2011 | Wuhan University Journal of Natural Sciences2011，16，2： | 2 |
| 18 | International reverse spillover effects on parent firms: Evidences from emerging-market MNEs in developed markets显示文摘 | Victor Zitian Chen Jing Li Daniel M. Shapiro | 2012 | European Management Journal2012，，3： | 1 |
| 19 | A new Hilbert-type integral inequality with some parameters and its reverse显示文摘 | XIE Zitian YANG Bicheng | 2008 | Kyungpook Mathe J2008，，48： | 1 |
| 20 | A Hilbert-type integral inequality whose kernel is a homogeneous form of degree-3显示文摘 | XIE Zitian ZENG Zheng | 2008 | J Math Appl2008，，339： | 1 |
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