采用计算流体动力学CFD(Computational Fluid Dynamics)与有限元FEA(Finite Element Analysis)耦合分析方法,建立缸体缸盖温度场模型和缸体缸盖强度分析模型。通过计算流体动力学分析计算了发动机额定工况下的缸内燃烧热负荷及缸内水套...采用计算流体动力学CFD(Computational Fluid Dynamics)与有限元FEA(Finite Element Analysis)耦合分析方法,建立缸体缸盖温度场模型和缸体缸盖强度分析模型。通过计算流体动力学分析计算了发动机额定工况下的缸内燃烧热负荷及缸内水套冷却边界,有限元分析加载装配预紧力及最大爆发压力进行强度计算,对计算结果进行后处理,得到缸孔变形相关值,并对其进行评估及优化。计算结果表明,优化缸体水套后,缸孔变形得到明显改善。展开更多
A novel in-situ process-Reaction Synthesis has been used to fabricate Al/TiC compos-ites,the phase constitute,microstructure and mechanical property of the Al/TiC composite have been investigated by the use of XRD and...A novel in-situ process-Reaction Synthesis has been used to fabricate Al/TiC compos-ites,the phase constitute,microstructure and mechanical property of the Al/TiC composite have been investigated by the use of XRD and SEM.It has been shown that the reaction synthesized TiC particu-late is submicron in size(about 0.1~0.8μpm),spherical in shape and smooth in surface.In macrostruc-ture the distribution of the TiC particulate in matrix is homogeneous,but in micostructure there is micro-segregation of the TiC particulate at the intergrannular.The cast structure become fine because of the existence of the TiC particulate.In addition«with the increasing of weight percentage of TiC partic-ulate in alloy,the yield strength and ultimate tensile strength of the composite increase significantly«e.g.at 15%TiC,117% and 103% increase respectively,in the same time the elongation of the composite is still more than 4.5%.In the end,the analysis has been done by SEM on the fracture morphology of the composite.The results show that the fracture is ductility,and mainly because of the cluster of TiC particulate to intergrannular and the synthesis of bar morphology Al_(3)Ti.展开更多
In this paper,the effects of aluminum content,C/Ti ratio and the size of powders on the phase constitute and micrography of reaction synthesis of Al+Ti+C system have been studied by the use of XRD and SEM.It has been ...In this paper,the effects of aluminum content,C/Ti ratio and the size of powders on the phase constitute and micrography of reaction synthesis of Al+Ti+C system have been studied by the use of XRD and SEM.It has been shown that with the increase of aluminum content,in addition to TiC,Al_3Ti phase is also synthesised,and the content of Al_3Ti increase,and the size of TiC become fine,changing from 0.4-1.4μm.The increase of C/Ti ratio is favorable to the synthesis of TiC and can increase the Al content in which only TiC phase has formed,and has no effect on the micrography of TiC,but shows great in fluence on the micrography,of Al_3Ti.In addition,the size of titanium has no effect on the phase constitue and micrography,but the size of aluminum has great in fluence on them.With the increase of size of aluminum powder,Al_3Ti will be synthesised and its content increase also,so it is unfavorable to the synthesis of TiC.展开更多
文摘采用计算流体动力学CFD(Computational Fluid Dynamics)与有限元FEA(Finite Element Analysis)耦合分析方法,建立缸体缸盖温度场模型和缸体缸盖强度分析模型。通过计算流体动力学分析计算了发动机额定工况下的缸内燃烧热负荷及缸内水套冷却边界,有限元分析加载装配预紧力及最大爆发压力进行强度计算,对计算结果进行后处理,得到缸孔变形相关值,并对其进行评估及优化。计算结果表明,优化缸体水套后,缸孔变形得到明显改善。
文摘A novel in-situ process-Reaction Synthesis has been used to fabricate Al/TiC compos-ites,the phase constitute,microstructure and mechanical property of the Al/TiC composite have been investigated by the use of XRD and SEM.It has been shown that the reaction synthesized TiC particu-late is submicron in size(about 0.1~0.8μpm),spherical in shape and smooth in surface.In macrostruc-ture the distribution of the TiC particulate in matrix is homogeneous,but in micostructure there is micro-segregation of the TiC particulate at the intergrannular.The cast structure become fine because of the existence of the TiC particulate.In addition«with the increasing of weight percentage of TiC partic-ulate in alloy,the yield strength and ultimate tensile strength of the composite increase significantly«e.g.at 15%TiC,117% and 103% increase respectively,in the same time the elongation of the composite is still more than 4.5%.In the end,the analysis has been done by SEM on the fracture morphology of the composite.The results show that the fracture is ductility,and mainly because of the cluster of TiC particulate to intergrannular and the synthesis of bar morphology Al_(3)Ti.
文摘In this paper,the effects of aluminum content,C/Ti ratio and the size of powders on the phase constitute and micrography of reaction synthesis of Al+Ti+C system have been studied by the use of XRD and SEM.It has been shown that with the increase of aluminum content,in addition to TiC,Al_3Ti phase is also synthesised,and the content of Al_3Ti increase,and the size of TiC become fine,changing from 0.4-1.4μm.The increase of C/Ti ratio is favorable to the synthesis of TiC and can increase the Al content in which only TiC phase has formed,and has no effect on the micrography of TiC,but shows great in fluence on the micrography,of Al_3Ti.In addition,the size of titanium has no effect on the phase constitue and micrography,but the size of aluminum has great in fluence on them.With the increase of size of aluminum powder,Al_3Ti will be synthesised and its content increase also,so it is unfavorable to the synthesis of TiC.
