MgAlON系复合材料的热震稳定性分析  

Thermal Shock Stability Analysis of MgAlON Composite Materials

作　　者：郭艳芹[1] GUO Yan-qin(Department of Engineering,Huanghe Science and Technology College,Zhengzhou 450063,China)

机构地区：[1]黄河科技学院工学部

出　　处：《硅酸盐通报》2019年第8期2426-2429,共4页Bulletin of the Chinese Ceramic Society

基　　金：河南省科技厅攻关项目(172102210383)

摘　　要：研究了不同骨料、不同基质及不同热震冷却方法对MgAlON系复合材料热震稳定性的影响。实验原料为骨料、基质料、结合剂(糊精),压制成型后1500℃高温氮化烧成。先测定烧成后试样的抗折强度;然后将试样1000℃埋碳处理后降至室温风冷循环三次,测其抗折强度;再将试件加热保温到设定温度后立即取出,放入循环水中进行水冷后测定其抗折强度σf;并计算热震前后试样残余强度保持率;利用SEM观察试样热震后的显微结构特征。实验研究表明:MgO-MgAl 2O 4-MgAlON系复合材料的临界热震温差ΔT C为400℃;热震后MgAl 2O 4-MgAlON复合材料的残余强度保持率较高,MgAlON弥散于基质材料中,起到了原位自补强作用;同种骨料的试样相比,氧化铝基试样热震后的残余强度保持率相对较高。The effects of different aggregates,different matrix material and different thermal shock cooling methods on the thermal shock staility of MgAlON composites were studied.Aggregate,matrix material and binder(dextrin)were used as raw materials in the experiment,the specimens were pressed into strips and nitrided at 1500℃.The flexural strength of sintered specimens was tested;then the specimens were reduced to room temperature air-cooled cycles three times after carbon embedding treatment at 1000℃,and the flexural strength was measured;secondly,the specimens were taken out immediately after heat preservation to set temperature and put into circulating water for water cooling,the flexural strength was measured;and the residual strength retention rate of the specimens before and after thermal shock was calculated;the microstructural characteristics of the specimens after the thermal shock were observed by SEM.The experimental results show that the critical thermal shock temperature differenceΔT C of MgO-MgAl 2O 4-MgAlON system composites is 400℃;the residual strength retention rate of MgAl 2O 4-MgAlON composites after thermal shock is higher,and MgAlON disperses in matrix materials and plays an in-situ self-reinforcing role;compared with the samples of the same aggregate,the residual strength retention rate of alumina-based composites after thermal shock is relatively higher.

关 键 词：三点弯曲法 抗折强度 热震稳定性 MgAlON系复合材料 

分 类 号：V254[一般工业技术—材料科学与工程]