Y_2O_3对SPS烧结纳米AlN粉末的影响  

Effects of Y_2O_3 on the SPS Sintering Nanometer AIN Powders

作　　者：杜学丽[1] 秦明礼[1] 冯培忠[1] 曲选辉[1] 

机构地区：[1]北京科技大学材料科学与工程学院

出　　处：《稀有金属材料与工程》2007年第A03期78-81,共4页Rare Metal Materials and Engineering

基　　金：国家杰出青年科学基金(50025412);国家"973"计划资助项目(TG2000067203)

摘　　要：利用低温燃烧法合成出了平均粒度为100 nm的AIN粉末,将合成的粉末采用放电等离子(SPS)技术进行低温强化烧结,研究Y_2O_3对烧结过程以及烧结试样特性的影响。XRD进行物相分析,SEM观察断口形貌,排水法测烧结试样的密度,激光闪光法测烧结试样的热导率。实验表明:采用低温燃烧法合成出的AlN粉末具有非常好的烧结性能,采用SPS烧结技术,40 MPa压力下,在1600℃保温4 min,就能得到非常致密的AlN陶瓷;Y_2O_3对纳米AlN粉末在SPS低温强化烧结过程仍有促进作用,使试样在更低的温度下烧结致密,并且晶粒更细小,从而热导率也较低;加入Y_2O_3的烧结试样晶界强度增加,断口中有较多的穿晶断裂形式,而不加入Y_2O_3的烧结试样主要以沿晶形式断裂。The nanometer AIN powders with mean grain size 100nm were synthesized by low-temperature combustion synthesis （LCS）. The synthesized powders were sintered through spark plasma sintering （SPS） technique in vacuum. The effects of Y2O3 on the SPS sintering process and sintered sample properties were investigated. X-ray diffraction （XRD） was used to identify the produced phases. The fracture surfaces of the sintered samples were observed by scanning electron microscopy （SEM）. The thermal diffusivity at room temperature was measured by a laser flash technique. Density of sintered specimen was measured by Archimedes displacement method. The result reveals that the nanometer AIN powders synthesized by LCS have excellent sintering property. The powder sintered by SPS at 1600 ℃ for 4 min at 40 MPa pressure fabricated the AIN ceramics with full density. Y2O3 promoted the SPS sintering process and made sintering temperature decrease that resulted in grain size and thermal conductivity of sintered sample deceasing. The fracture mode of sintered sample doped with Y2O3 was transgranular/intergranular mixed fracture due to grain-boundary strength increasing, and that was mainly intergranular fracture for sintered sample with no Y2O3.

关 键 词：AIN陶瓷 氧化钇 低温燃烧法 放电等离子烧结 

分 类 号：TB383.1[一般工业技术—材料科学与工程] TF124.5[冶金工程—粉末冶金]