Research On Properties Of Steel Fiber Reinforced Ceramic Matrix Composites

Along with rapid development of science and technology,more properties of material are required by many fields.The composite of materials is a good way to enhance the properties,when traditional materials can not satisfy the requirements. Ceramic,which is the one of three most important kinds of materials,how to deal with the brittle become the key of their composites.Currently,there are many ways to enhance CMCs,and they have made grant achievement.But now,it is less research on CMCs which enhanced by steel fibers,and cooperating with other factors.Al₂O₃-ZrO₂-TiO₂ has been chosen for the main part of CMCs,with a BN and clay helping sinter,and steel fibers for enhancing the properties of CMCs,under the fixed sinter ruler,to obtain CMCs enhanced by steel fiber under 1200℃.This kind of material is SFRCMCs.In this paper,the experiments include researchs on the properties of SFRCMCs from forming factors(including binder and forming pressure),the ratio of main part and the size of Al₂O₃ powder,by some tests and discussions.With the result of experiments,the ratio of main part and the size of powder are the each one of the most important factors to influence the properties of SFRCMCs.At last one of the samples has a good property compared with others (273.62MPa in compression strength and 73.68MPa in bending strength),when the ratio of Al₂O₃-ZrO₂-TiO₂ to be 50:15:15,and chosen an appropriate size of Al₂O₃ powder(50μm),and excluding the factors of forming.The ratio of steel fiber is 10%(wt%).Then,increasing the ratio of steel fibers based on the results of last experiment, and researching the properties of the samples.It has displayed that with the increasing of steel fibers,the properties of SFRCMCs has improved at first and then declined when the ratio of steel fibers is very high.The sample content 24%(wt%) steel fibers has better properties(364.56MPa in compression strength and 103.54MPa in bending strength) compared with other samples.The other result is that long steel fiber is better than short fiber when they reinforcing CMCs. Decreasing;the ratio of steel fiber to 18%(wt%),and adding 6%(wt%) with different kinds of metal powder(Cu,Ni,Fe,Fe₃Al).The result showed that,the properties of samples have been reinforced in varying degrees,and the sample with Fe powder for addition has the best properties(435.68MPa in compression strength and 127.47MPa in bending strength).The metal powder may improve the binding of interface between ceramics and steel fibers,and remedy the defects of bad compatibility of ceramics and steel fibers.