【作者】 隋洲；

【导师】 朱兆军；

【作者基本信息】 哈尔滨工业大学 ， 材料加工工程， 2010， 硕士

【摘要】 3D-Ka gome夹芯结构是近年来提出的一种力学性能十分优异的新型点阵夹芯结构。与金字塔型、四面体型芯子结构相比，3D-Ka gome芯子结构有更高的强度、更好的抗屈曲性能和各向同性特性。本文以3D-Ka gome夹芯结构为研究对象，采用AnyCasting铸造模拟软件对Inconel718镍基高温合金熔模精密铸造3D-Ka gome夹芯结构的过程进行数值模拟仿真，分析了浇注系统、型壳预热温度及浇注温度对铸件成形性的影响，并研究了合金的显微组织及力学性能。针对3D-Ka gome结构的特点，设计了3种缝隙式浇注系统，分别对3种浇注系统的充型凝固过程进行数值模拟，并采用Niya ma判据对凝固过程中可能产生的缩孔、缩松缺陷进行了预测分析。Inconel718镍基高温合金的充型及凝固过程的缺陷预测表明，同一种浇注系统，在型壳预热温度不变的条件下，缺陷出现的概率随着浇注温度的提高而降低，但是浇注温度过高，出现缺陷的概率反而更高；在浇注温度不变的条件下，型壳预热温度提高有利于铸件的成形，但是过高的型壳预热温度增大了缩孔、缩松缺陷的趋势；随着缝隙式浇道的宽度及浇道数量的增加，出现缺陷的概率亦随之减少。因此对浇注系统、型壳预热温度及浇注温度进行了正交实验分析，发现采用双缝隙式浇注系统，浇注温度为1460℃，型壳预热温度为860℃的情况下，缺陷出现的概率最小。本文在优化后的工艺参数条件下，用Inconel718镍基高温合金对3D-Ka gome结构进行真空熔模精密铸造，浇注后的铸件充型完好，表面光滑。更多还原

【Abstract】 Sand wich structure with 3D-Ka gome truss core, a new truss core structurewith superior mecha nica l, is brought forward in recent years. Compared withpyra mida l and tetra hed ral truss cores, 3D-Ka gome truss core possesses the higherstrength, grea t resista nc e to plastic buck ling and the excellent isotropicperforma nce.In this paper, 3D-Ka gome truss core was considered as the object of study,based on AnyCasting of casting process simula tion softwa re. The numerica lsimula tion process of the 3D-Ka gome truss core on Inconel718 supera lloyinvestment casting was ana lysied. The effects of ga ting system, parameters(pouringtemperature and prehea ted temperature of shell mould ) to the figura tion of trusscore were also resea rched , and studied the microstructures and mecha nica lproperty of Inconel718 supera lloy.To understa nd the characteristics of investment casting of 3D-Ka gome trusscore, different ga ting systems were designed. In addition, the defect of the trusscore panels was pred icted by the criterion of Niya ma: the poles in the midd le of thetruss core panels were the most likely to form shrinka ge cavity and porosity.The defect pred iction in filling seq uence and solid ifica tion seq uence ofsupera lloy Inconel718 showed tha t the probability of defect decreased with theincreasing of the pouring temperature when the prehea ted temperature of the shellmould was content, ho wever the probability of defect increased when pouringtemperature was too high; higher prehea ted temperature of shell mould was benefitfor figura tion of truss core when the pouring temperature was fixed, but theprobability of defects increased if the prehea ted temperature of shell mould was toohigh; the probability of defects decreased with wid th and increasing qua ntity of slotga ting system, too. Therefore, the effects of slot ga ting system, pouring temperatureand prehea ted temperature of shell mould based on orthogona l test were disscussed,we obta ined tha t the optimum combina tion was when the pouring temperature was1460℃, prehea ted temperature of shell mould was 860℃with double slot ga tingsystem.The 3D-Ka gome truss core was successfully cast on Inconel718 supera lloy invacuum ind uction furnace on the cond ition sta ted above.更多还原