The first micro-segregation under conditions of twin roll strip casting was simulated.The relationship between the temperature and solid fraction in the mushy zone was given.The temperatures such as ZDT,LIT were got f...The first micro-segregation under conditions of twin roll strip casting was simulated.The relationship between the temperature and solid fraction in the mushy zone was given.The temperatures such as ZDT,LIT were got from this simulation.Then using the turbulent model,the flow field and thermal field in the pool of twin-roll strip caster was simulated.The speed and temperature at different casting speed was given,and the results were also explained.By these two simulations,the appropriate casting speed can be found.These simulations can provide effective data for controlling the twin-roll strip casting process.展开更多
The influence of solid fraction of Al 28Pb alloy mushy on distribution of Pb in Al Pb ingot was studied. The special electromagnetic stirring apparatus was used to prepare Al 28Pb alloy mushy and the relationship betw...The influence of solid fraction of Al 28Pb alloy mushy on distribution of Pb in Al Pb ingot was studied. The special electromagnetic stirring apparatus was used to prepare Al 28Pb alloy mushy and the relationship between solid fraction and stirring temperature was gotten. The results show that when solid fraction of Al 28Pb alloy mushy is less than 45%, Pb precipitation usually happens in the ingot. However, Pb precipitation in casting reduces gradually with increasing solid fraction of mushy, and when solid fraction is larger than 45%, Pb precipitation in casting can be removed. [展开更多
Al-7graphite composite was processed using Al-7graphite mushy prepared by electromagnetic-mechanical stirring method, and the influence of solid fraction on the distributing of graphite particles in ingot was studied....Al-7graphite composite was processed using Al-7graphite mushy prepared by electromagnetic-mechanical stirring method, and the influence of solid fraction on the distributing of graphite particles in ingot was studied. The results shows that the relationship between solid fraction and stirring temperature of mushy is: f(s) = 591.5-0.897 t (where f(s) is the solid fraction, t is the stirring temperature). For Al-7graphite composite, with the increasing of solid fraction, the aggregation extent of graphite particles reduced gradually, and when solid fraction was larger than 30%, graphite particles could distribute evenly in ingot.展开更多
Heat transfer at the metal-die interface has a great influence on the solidification process and casting structure. As thin-wall components are extensively produced by high pressure die casting process(HPDC), the B390...Heat transfer at the metal-die interface has a great influence on the solidification process and casting structure. As thin-wall components are extensively produced by high pressure die casting process(HPDC), the B390 alloy finger-plate casting was cast against an H13 steel die on a cold-chamber HPDC machine. The interfacial heat transfer behavior at different positions of the die was carefully studied using an inverse approach based on the temperature measurements inside the die. Furthermore, the filling process and the solidification rate in different finger-plates were also given to explain the distribution of interfacial heat flux(q) and interfacial heat transfer coefficient(h). Measurement results at the side of sprue indicates that qmax and hmax could reach 9.2 MW·m^(-2) and 64.3 kW ·m^(-2)·K^(-1), respectively. The simulation of melt flow in the die reveals that the thinnest(T_1) finger plate could accelerate the melt flow from 50 m·s^(-1) to 110 m·s^(-1). Due to this high velocity, the interfacial heat flux at the end of T_1 could firstly reach a highest value 7.92 MW·m^(-2) among the ends of T_n(n=2,3,4,5). In addition, the q_(max) and h_(max) values of T_2, T_4 and T_5 finger-plates increase with the increasing thickness of the finger plate. Finally, at the rapid decreasing stage of interfacial heat transfer coefficient(h), the decreasing rate of h has an exponential relationship with the increasing rate of solid fraction(f).展开更多
Anaerobic digestion(AD)as a waste management method has the potential to reduce greenhouse gas emissions while pro-ducing renewable energy,making it a viable option for managing the organic fraction of municipal solid...Anaerobic digestion(AD)as a waste management method has the potential to reduce greenhouse gas emissions while pro-ducing renewable energy,making it a viable option for managing the organic fraction of municipal solid waste(OFMSW).OFMSW characteristics can vary depending on factors such as waste source,composition and separation units.The charac-teristics of OFMSW are critical for analyzing and monitoring the AD process to optimize biogas production.In this study,the waste composition and physicochemical characteristics of the mechanically separated OFMSW(ms-OFMSW)were determined at a full-scale AD plant in Turkiye.The ms-OFMSW samples were collected monthly after mechanical separation and were subsequently sent to the anaerobic digester.The composition and physicochemical characteristics of the samples were determined by manual sorting.The results showed that the majority of the ms-OFMSW(76.45%±1.71%)was organic,while 8.99%±1.56%was recyclable and 14.56%±1.69%was non-recyclable.Loss of environmental benefits for the recyclable materials was determined using a free online tool provided by Environmental Protection Agency.Metals(399.7 GJ)and plas-tics(403.7 GJ)both saved nearly the same amount of energy while metals saved the most water(421.8 m3),with the greatest positive impact.Greenhouse benefits ranged from 3 tons to 40 tons of carbon dioxide equivalent for each waste stream.These findings suggest that efficient pre-separation units can improve the anaerobic digestibility of OFMSW,while also providing greater environmental benefits by preventing recyclable waste from the anaerobic digester.In addition to encouraging source separation applications,this study demonstrates the need for improved technologies to separate OFMSW from mixed MSW.展开更多
A mathematic model of the solid fraction during rheo-casting by the cooling sloping plate process was established, and the effects of the process parameters on the solid fraction were analyzed. The calculation results...A mathematic model of the solid fraction during rheo-casting by the cooling sloping plate process was established, and the effects of the process parameters on the solid fraction were analyzed. The calculation results show that the experimental result is approximately agreed with the calculation value. The effect of the casting temperature on the change rate of the solid fraction is not obvious. But the beginning solidification length is greatly influenced by the casting temperature. The beginning solidification length increases with the increment of the casting temperature. The effect of the sloping angle on the solid fraction becomes obvious with the increment of the sloping plate length. The solid fraction increases sharply with the decrease of the initial thickness of the melt. The melt initial thickness between 15 and 20 mm is suggested.展开更多
A numerical model was developed to simulate the jet-flow solid fraction of W18Cr4 V high-speed steel during spray forming. The whole model comprises two submodels: one is an individual droplet model, which describes t...A numerical model was developed to simulate the jet-flow solid fraction of W18Cr4 V high-speed steel during spray forming. The whole model comprises two submodels: one is an individual droplet model, which describes the motion and thermal behaviors of individual droplets on the basis of Newton's laws of motion and the convection heat transfer mechanism; the other is a droplet distribution model, which is used to calculate the droplet size distribution. After being verified, the model was used to analyze the effects of parameters, including the initial gas velocity, deposition distance, superheat degree, and the ratio of gas-to-metal mass flow rates, on the jet-flow solid fraction. Finally, an equation to predict the jet-flow solid fraction directly and conveniently according to the parameters was presented. The values predicted by the equation show good agreement with those calculated by the numerical model.展开更多
The key factor in semi-solid metal processing is the solid fraction at the forming temperature because it affects the microstructure and mechanical properties of the thixoformed components. Though an enormous amount o...The key factor in semi-solid metal processing is the solid fraction at the forming temperature because it affects the microstructure and mechanical properties of the thixoformed components. Though an enormous amount of data exists on the solid fraction-temperature re- lationship in A356 alloy, information regarding the solid fraction evolution characteristics of A356-TiB2 composites is scarce. The present article establishes the temperature-solid fraction correlation in A356 alloy and A356-xTiB2 （x = 2.5wt% and 5wt%） composites using dif- ferential thermal analysis （DTA）. The DTA results indicate that the solidification characteristics of the composites exhibited a variation of 2℃ and 3℃ in liquidus temperatures and a variation of 3℃ and 5℃ in solidus temperatures with respect to the base alloy. Moreover, the eutectic growth temperature and the solid fraction（fs） vs. temperature characteristics of the composites were found to be higher than those of the base alloy. The investigation revealed that in-situ formed TiB2 particles in the molten metal introduced more nucleation sites and reduced undercooling.展开更多
The solid circulation rate is essential for design of pressurized circulating fluidized beds(PCFBs).With increasing pressure from atmospheric pressure to a few bars,the gas density linearly increases with the pressure...The solid circulation rate is essential for design of pressurized circulating fluidized beds(PCFBs).With increasing pressure from atmospheric pressure to a few bars,the gas density linearly increases with the pressure,which affects the gas-solid flow characteristics.In this work,experiments were performed at room temperature in a cold PCFB apparatus with a riser of 3.3 m in height and 0.05 m in diameter.The solid circulation rate was studied from 20 to 80 kg/(m^(2)·s)under various conditions with increasing pressure from 0.1 to 0.6 MPa and fluidizing gas velocity from around 1.5 to 8.0 m/s for different Geldart B group particles.Most of the conditions were in the flow regimes of core-annulus flow(CAF)only and CAF with a turbulent fluidized bed at the bottom.The trend of the apparent slip factor with the dimensionless slip velocity was similar at different pressures and for different average particle sizes,and it converged to an exponential function.An empirical equation was obtained by fitting the solid circulation rate with the operating parameters(particle transport velocity,particle volume fraction,Archimedes number,and Froude number),which is helpful for design and operation of PCFBs.展开更多
Solidification experiments of Cr steel under linear EMS were conducted to investigate the columnar-to-equiaxed transition(CET).The results are compared with those in carbon steel to clarify effect of Cr content and EM...Solidification experiments of Cr steel under linear EMS were conducted to investigate the columnar-to-equiaxed transition(CET).The results are compared with those in carbon steel to clarify effect of Cr content and EMS.The conclusions are as follow:The criterion for dendrite fragmentation under linear EMS is obtained and verified by previous paper,then is considered valid for Cr steel.Investigation is carried out on the relation between the superficial velocity in the bulk flow and critical solid fraction at the time of dendrite fragmentation(CET occurrence).The critical solid fraction is smaller in high Cr case.As a result,the CET occurrence is more difficult in this case.展开更多
A traditional semisolid processing based on the rheological properties of semisolid alloy is very difficult in manufacturing the semisolid slurry because of the chase for spherical,fine and high solid fraction of the ...A traditional semisolid processing based on the rheological properties of semisolid alloy is very difficult in manufacturing the semisolid slurry because of the chase for spherical,fine and high solid fraction of the primary solid in the slurry.Through many experiments,it is found that it is not very necessary to excessively emphasize the glomeration and high solid fraction considering of the facts that the rheological properties of the semisolid slurry is controlled by not only the microstructure of the primary solid but also the rheological conditions.The manufacturing slurry can be simply regarded as preparing the semisolid alloy melt,therefore,a modified semisolid processing technology is presented.Its procedure consists of three basic steps,such as preparing slurry,filling mould cavity and solidification with pressure.The basic aim of the preparing slurry is to obtain the slurry containing 5%-20%(volume fraction) primary solid with particle or stick instead of spherical morphology.The experiment results show that,with the modified rheological processing technology,many steel and nonferrous alloy products are industrially produced.展开更多
The aim of this work is to attempt the application of A357 Al-Si-Mg cast alloy in the thixoextrusion process,evaluating the different forming parameters effect.Thixoextrusion offers several advantages compared with tr...The aim of this work is to attempt the application of A357 Al-Si-Mg cast alloy in the thixoextrusion process,evaluating the different forming parameters effect.Thixoextrusion offers several advantages compared with traditional hot-extrusion such as lower pressure,minor friction forces,higher material fluidity and longer tool life.This type of semi-solid process requires high solid fraction(0.7<fs<1) materials because of its low solidification rate.Aluminium alloy A357 is a commercial cast alloy characterized by high strength,ductility and corrosion resistance.It is commonly used for cast production of automotive components and it is also suitable for semi-solid process,due to its wide range of solidification.A357 aluminium alloy was used as a feedstock for thixoextrusion in order to investigate thixoformability at high solid fraction.A357 alloy with high solid fraction(>0.85) is less sensitive to temperature drops and allows more stable material flow at higher speeds.To know the forming parameters that improve the mechanical properties of thixoextruded parts,some extrusion tests were carried out.The results were used as the main criteria for assessing the thixoforming viability of the A357 alloy.展开更多
Green-Naghdi （G-N） theory of thermoelasticity is employed to study the deformation of micropolar thermoelastic solid with voids considering the influence of various sources acting on the plane surface. The normal mo...Green-Naghdi （G-N） theory of thermoelasticity is employed to study the deformation of micropolar thermoelastic solid with voids considering the influence of various sources acting on the plane surface. The normal mode analysis is used to obtain the analytical expressions of the displacement components, force stress, coupled stress, variation of volume fraction field and temperature distribution. The computed results are presented graphically when the volume source is applied. Comparisons of type II and type III with and without micropolarity effect are made with the results predicted in the context of （G-N） theory.展开更多
The bonding of steel-mushy Al-7graphite was studied. The relationship between interfacial shear strength of bonding plate and solid fraction of Al-7graphite mushy was obtained, and the interfacial structure of bonding...The bonding of steel-mushy Al-7graphite was studied. The relationship between interfacial shear strength of bonding plate and solid fraction of Al-7graphite mushy was obtained, and the interfacial structure of bonding plate was determined. The results showed that: under the condition of 500 degreesC for preheat temperature of steel plate and 10 mm/s for rolling speed, the largest interfacial shear strength of bonding plate was 70.1 MPa when solid fraction of Al-7graphite mushy was 34.6%.展开更多
基金Item Sponsored by National Natural Science Foundation(59995440)
文摘The first micro-segregation under conditions of twin roll strip casting was simulated.The relationship between the temperature and solid fraction in the mushy zone was given.The temperatures such as ZDT,LIT were got from this simulation.Then using the turbulent model,the flow field and thermal field in the pool of twin-roll strip caster was simulated.The speed and temperature at different casting speed was given,and the results were also explained.By these two simulations,the appropriate casting speed can be found.These simulations can provide effective data for controlling the twin-roll strip casting process.
文摘The influence of solid fraction of Al 28Pb alloy mushy on distribution of Pb in Al Pb ingot was studied. The special electromagnetic stirring apparatus was used to prepare Al 28Pb alloy mushy and the relationship between solid fraction and stirring temperature was gotten. The results show that when solid fraction of Al 28Pb alloy mushy is less than 45%, Pb precipitation usually happens in the ingot. However, Pb precipitation in casting reduces gradually with increasing solid fraction of mushy, and when solid fraction is larger than 45%, Pb precipitation in casting can be removed. [
基金China and Tsinghua-Zhongda Postdoctoral Science Foundation.]
文摘Al-7graphite composite was processed using Al-7graphite mushy prepared by electromagnetic-mechanical stirring method, and the influence of solid fraction on the distributing of graphite particles in ingot was studied. The results shows that the relationship between solid fraction and stirring temperature of mushy is: f(s) = 591.5-0.897 t (where f(s) is the solid fraction, t is the stirring temperature). For Al-7graphite composite, with the increasing of solid fraction, the aggregation extent of graphite particles reduced gradually, and when solid fraction was larger than 30%, graphite particles could distribute evenly in ingot.
基金financially supported by the class General Financial Grant from the China Postdoctoral Science Foundation(No.2015M580093)the National Nature Science Foundation of China(No.20151301587)the National Major Science and Technology Program of China(No.2012ZX04012011)
文摘Heat transfer at the metal-die interface has a great influence on the solidification process and casting structure. As thin-wall components are extensively produced by high pressure die casting process(HPDC), the B390 alloy finger-plate casting was cast against an H13 steel die on a cold-chamber HPDC machine. The interfacial heat transfer behavior at different positions of the die was carefully studied using an inverse approach based on the temperature measurements inside the die. Furthermore, the filling process and the solidification rate in different finger-plates were also given to explain the distribution of interfacial heat flux(q) and interfacial heat transfer coefficient(h). Measurement results at the side of sprue indicates that qmax and hmax could reach 9.2 MW·m^(-2) and 64.3 kW ·m^(-2)·K^(-1), respectively. The simulation of melt flow in the die reveals that the thinnest(T_1) finger plate could accelerate the melt flow from 50 m·s^(-1) to 110 m·s^(-1). Due to this high velocity, the interfacial heat flux at the end of T_1 could firstly reach a highest value 7.92 MW·m^(-2) among the ends of T_n(n=2,3,4,5). In addition, the q_(max) and h_(max) values of T_2, T_4 and T_5 finger-plates increase with the increasing thickness of the finger plate. Finally, at the rapid decreasing stage of interfacial heat transfer coefficient(h), the decreasing rate of h has an exponential relationship with the increasing rate of solid fraction(f).
基金the Scientific Research Project supported by The Istanbul Technical University,Turkiye(Yagmur Kabakci,Project No.MDK-2019-42183)The authors gratefully acknowledge to Duzce Solid Waste Association,Project No.5218B04.
文摘Anaerobic digestion(AD)as a waste management method has the potential to reduce greenhouse gas emissions while pro-ducing renewable energy,making it a viable option for managing the organic fraction of municipal solid waste(OFMSW).OFMSW characteristics can vary depending on factors such as waste source,composition and separation units.The charac-teristics of OFMSW are critical for analyzing and monitoring the AD process to optimize biogas production.In this study,the waste composition and physicochemical characteristics of the mechanically separated OFMSW(ms-OFMSW)were determined at a full-scale AD plant in Turkiye.The ms-OFMSW samples were collected monthly after mechanical separation and were subsequently sent to the anaerobic digester.The composition and physicochemical characteristics of the samples were determined by manual sorting.The results showed that the majority of the ms-OFMSW(76.45%±1.71%)was organic,while 8.99%±1.56%was recyclable and 14.56%±1.69%was non-recyclable.Loss of environmental benefits for the recyclable materials was determined using a free online tool provided by Environmental Protection Agency.Metals(399.7 GJ)and plas-tics(403.7 GJ)both saved nearly the same amount of energy while metals saved the most water(421.8 m3),with the greatest positive impact.Greenhouse benefits ranged from 3 tons to 40 tons of carbon dioxide equivalent for each waste stream.These findings suggest that efficient pre-separation units can improve the anaerobic digestibility of OFMSW,while also providing greater environmental benefits by preventing recyclable waste from the anaerobic digester.In addition to encouraging source separation applications,this study demonstrates the need for improved technologies to separate OFMSW from mixed MSW.
基金supported by the National Natural Science Foundation of China (Nos.51034002 and 50974038)National Program for Fundamental Research and Development of China (No.2011CB610405)
文摘A mathematic model of the solid fraction during rheo-casting by the cooling sloping plate process was established, and the effects of the process parameters on the solid fraction were analyzed. The calculation results show that the experimental result is approximately agreed with the calculation value. The effect of the casting temperature on the change rate of the solid fraction is not obvious. But the beginning solidification length is greatly influenced by the casting temperature. The beginning solidification length increases with the increment of the casting temperature. The effect of the sloping angle on the solid fraction becomes obvious with the increment of the sloping plate length. The solid fraction increases sharply with the decrease of the initial thickness of the melt. The melt initial thickness between 15 and 20 mm is suggested.
基金financially supported by the National High-Tech Research and Development Program of China (No. 2012AA03A509)the National Natural Science Foundation of China (No. 51204015)
文摘A numerical model was developed to simulate the jet-flow solid fraction of W18Cr4 V high-speed steel during spray forming. The whole model comprises two submodels: one is an individual droplet model, which describes the motion and thermal behaviors of individual droplets on the basis of Newton's laws of motion and the convection heat transfer mechanism; the other is a droplet distribution model, which is used to calculate the droplet size distribution. After being verified, the model was used to analyze the effects of parameters, including the initial gas velocity, deposition distance, superheat degree, and the ratio of gas-to-metal mass flow rates, on the jet-flow solid fraction. Finally, an equation to predict the jet-flow solid fraction directly and conveniently according to the parameters was presented. The values predicted by the equation show good agreement with those calculated by the numerical model.
基金financial support from the Indian Institute of Technology Bhubaneswar under the SEED project grant for fabricating the "cooling slope casting" experimental setupthe support extended by Central Research Facility (CRF), Indian Institute of Technology Kharagpur, toward the facility for conducting DTA experiments
文摘The key factor in semi-solid metal processing is the solid fraction at the forming temperature because it affects the microstructure and mechanical properties of the thixoformed components. Though an enormous amount of data exists on the solid fraction-temperature re- lationship in A356 alloy, information regarding the solid fraction evolution characteristics of A356-TiB2 composites is scarce. The present article establishes the temperature-solid fraction correlation in A356 alloy and A356-xTiB2 （x = 2.5wt% and 5wt%） composites using dif- ferential thermal analysis （DTA）. The DTA results indicate that the solidification characteristics of the composites exhibited a variation of 2℃ and 3℃ in liquidus temperatures and a variation of 3℃ and 5℃ in solidus temperatures with respect to the base alloy. Moreover, the eutectic growth temperature and the solid fraction（fs） vs. temperature characteristics of the composites were found to be higher than those of the base alloy. The investigation revealed that in-situ formed TiB2 particles in the molten metal introduced more nucleation sites and reduced undercooling.
基金Financial support to this work by the National Key Research and Development Program of China(No.2016YFB0600802)is gratefully acknowledged.
文摘The solid circulation rate is essential for design of pressurized circulating fluidized beds(PCFBs).With increasing pressure from atmospheric pressure to a few bars,the gas density linearly increases with the pressure,which affects the gas-solid flow characteristics.In this work,experiments were performed at room temperature in a cold PCFB apparatus with a riser of 3.3 m in height and 0.05 m in diameter.The solid circulation rate was studied from 20 to 80 kg/(m^(2)·s)under various conditions with increasing pressure from 0.1 to 0.6 MPa and fluidizing gas velocity from around 1.5 to 8.0 m/s for different Geldart B group particles.Most of the conditions were in the flow regimes of core-annulus flow(CAF)only and CAF with a turbulent fluidized bed at the bottom.The trend of the apparent slip factor with the dimensionless slip velocity was similar at different pressures and for different average particle sizes,and it converged to an exponential function.An empirical equation was obtained by fitting the solid circulation rate with the operating parameters(particle transport velocity,particle volume fraction,Archimedes number,and Froude number),which is helpful for design and operation of PCFBs.
基金Item Sponsored by the Central Universities (N100409010) Project for Key Laboratory of Liaoning Province (LS2010065) +1 种基金"111 project"of Northeastern UniversityChina (B07015)
文摘Solidification experiments of Cr steel under linear EMS were conducted to investigate the columnar-to-equiaxed transition(CET).The results are compared with those in carbon steel to clarify effect of Cr content and EMS.The conclusions are as follow:The criterion for dendrite fragmentation under linear EMS is obtained and verified by previous paper,then is considered valid for Cr steel.Investigation is carried out on the relation between the superficial velocity in the bulk flow and critical solid fraction at the time of dendrite fragmentation(CET occurrence).The critical solid fraction is smaller in high Cr case.As a result,the CET occurrence is more difficult in this case.
基金Project supported by Beijing Natural Science Foundation (3093024)Project supported by Technology Foundation of Beijing Jiaotong University (2007XM035)
文摘A traditional semisolid processing based on the rheological properties of semisolid alloy is very difficult in manufacturing the semisolid slurry because of the chase for spherical,fine and high solid fraction of the primary solid in the slurry.Through many experiments,it is found that it is not very necessary to excessively emphasize the glomeration and high solid fraction considering of the facts that the rheological properties of the semisolid slurry is controlled by not only the microstructure of the primary solid but also the rheological conditions.The manufacturing slurry can be simply regarded as preparing the semisolid alloy melt,therefore,a modified semisolid processing technology is presented.Its procedure consists of three basic steps,such as preparing slurry,filling mould cavity and solidification with pressure.The basic aim of the preparing slurry is to obtain the slurry containing 5%-20%(volume fraction) primary solid with particle or stick instead of spherical morphology.The experiment results show that,with the modified rheological processing technology,many steel and nonferrous alloy products are industrially produced.
基金the University of Liège for the experimental supportthe Walloon Region (First Europe project)the COST 541 for their financial support
文摘The aim of this work is to attempt the application of A357 Al-Si-Mg cast alloy in the thixoextrusion process,evaluating the different forming parameters effect.Thixoextrusion offers several advantages compared with traditional hot-extrusion such as lower pressure,minor friction forces,higher material fluidity and longer tool life.This type of semi-solid process requires high solid fraction(0.7<fs<1) materials because of its low solidification rate.Aluminium alloy A357 is a commercial cast alloy characterized by high strength,ductility and corrosion resistance.It is commonly used for cast production of automotive components and it is also suitable for semi-solid process,due to its wide range of solidification.A357 aluminium alloy was used as a feedstock for thixoextrusion in order to investigate thixoformability at high solid fraction.A357 alloy with high solid fraction(>0.85) is less sensitive to temperature drops and allows more stable material flow at higher speeds.To know the forming parameters that improve the mechanical properties of thixoextruded parts,some extrusion tests were carried out.The results were used as the main criteria for assessing the thixoforming viability of the A357 alloy.
文摘Green-Naghdi （G-N） theory of thermoelasticity is employed to study the deformation of micropolar thermoelastic solid with voids considering the influence of various sources acting on the plane surface. The normal mode analysis is used to obtain the analytical expressions of the displacement components, force stress, coupled stress, variation of volume fraction field and temperature distribution. The computed results are presented graphically when the volume source is applied. Comparisons of type II and type III with and without micropolarity effect are made with the results predicted in the context of （G-N） theory.
基金This work was financially supported by the China and Tsinghua-Zhongda Postdoctoral Science Foundation.
文摘The bonding of steel-mushy Al-7graphite was studied. The relationship between interfacial shear strength of bonding plate and solid fraction of Al-7graphite mushy was obtained, and the interfacial structure of bonding plate was determined. The results showed that: under the condition of 500 degreesC for preheat temperature of steel plate and 10 mm/s for rolling speed, the largest interfacial shear strength of bonding plate was 70.1 MPa when solid fraction of Al-7graphite mushy was 34.6%.
