Al_2O_3纤维含量对硅基陶芯性能的影响及增强机制  

Effects of Al_2O_3 Fiber Content on Properties of Silicon-based Ceramic Core and Strengthening Mechanism

作　　者：黄嘉俊 严青松 芦刚 饶文杰 于航 Huang Jiajun;Yah Qingsong;Lu Gang;Rao Wenjie;Yu Hang(National Defence Key Discipline Laboratory of Light Alloy Processing Science and Technology,Nanchang Hangkong Universit)

机构地区：[1]南昌航空大学轻合金加工科学与技术国防重点学科实验室

出　　处：《特种铸造及有色合金》2018年第11期1234-1238,共5页Special Casting & Nonferrous Alloys

基　　金：江西省教育厅科技资助项目(GJJ160687)

摘　　要：为提高硅基陶瓷型芯性能,将不同含量的Al_2O_3纤维添加至型芯浆料中,采用热压注法造芯,研究不同Al_2O_3纤维添加量下型芯抗弯强度及气孔率的变化,并观察试样断面微观形貌。结果表明,添加Al_2O_3纤维对陶瓷型芯抗弯强度和气孔率影响显著,纤维含量为1%,型芯抗弯强度达到最大值,为20.48MPa;纤维含量为0.75%,型芯气孔率达到最大值为36.16%;纤维添加量超过1%,纤维分散性较差,纤维桥联作用发挥不明显,增强效果削弱。Al_2O_3纤维增强陶瓷型芯包括两种机制:桥联增强和拔出增强。In order to improve the properties of silicon based ceramic core,the Al2O3 fibers with different content were added to the core slurry,and the core was made by hot pressure casting.The change of the bending strength and porosity of the core with different Al2O3 fibers was analyzed,and the microstructure of the sample was observed.The results show that the effect of Al2O3 fiber on the flexural strength and porosity of the ceramic core is significant.With the fiber content of 1%,the core flexural strength reaches the maximum value of 20.48 MPa,and with the fiber content of 0.75%,the porosity of the core is 36.16%.However,with the fiber addition more than 1%,the fiber presents poor dispersion,and the fiber bridging action is weak,so the enhancement effect is weakened.Al2O3 fiber reinforced ceramic core includes two mechanisms,bridging enhancement and pull-out enhancement.

关 键 词：硅基陶瓷型芯 AL2O3纤维 抗弯强度 气孔率 

分 类 号：TQ174.75[化学工程—陶瓷工业] TB331[化学工程—硅酸盐工业]