凝胶离心成形制备YG10硬质合金管  

CENTRIFUGAL GEL FORMING FOR PREPARATION OF YG10 CEMENTED CARBIDE PIPE

作　　者：石永亮[1] 郭志猛[1] 方哲成[1] 曾鲜[1] 

机构地区：[1]北京科技大学,北京100083

出　　处：《粉末冶金工业》2012年第2期44-48,共5页Powder Metallurgy Industry

基　　金：广东省产学研结合项目"微(纳)米级晶粒硬质合金制品研发及产业化"(2009A090100014)

摘　　要：将凝胶离心成形工艺应用于YG10复合粉末的坯体成形,研究了固含量对YG10复合粉末浆料的流变性的影响,分析了凝胶离心成形过程中引发剂量和压力对聚合速率的影响,并研究了离心转速对坯体和烧结体性能的影响。结果表明:以油酸作分散剂,制备稳定且流动性好的浆料最佳固含量为50%(体积分数),引发剂的加入量为5mmol/L(相对于预混液的体积),凝胶离心成形过程中压力能够加速浆料的固化,采用自行设计的离心成型机,选择最佳转速4 000r/min,制备出的坯体密度高、无残留气孔,相对密度57%,强度28.3MPa。坯体经真空脱胶烧结1 420℃保温1h制备出YG10硬质合金管,烧结体收缩均匀无变形,组织结构完整无偏析。Centrifugal gel forming was applied to the molding of YG10 composite powders.The effect of the solids loading on the rheological behavior of YG10 composite powders slurry was investigated.The effect of the initiator amount and pressure on polymerization rate was anlysized.Moreover,the effect of the rotationl speed on the green and sintered bodies was also investigated.The results show that,the YG10 composite powders have a good dispersibility in the HEMA gel system.Using oleic acid as dispersant,the slurry with good flowability and good stability and maximum solids loading of 50vol% can be obtained.The amout of initiator is 5 mmol/L（based on the volume of the premix）.In the centrifugal gel forming process,pressure can accelerate the solidification of the slurry.The green body with high density,without residue pores,the strength of 28.3 MPa and relative density of 57% was prepared by choosing the optimum rotate speed of 4 000 r/min and using our device.YG10 cemented carbide pipe was prepared by sintering at 1 420℃ for 1 h in vacuum.It has uniform shrinkage without deformation,and the microstructure has no segregation.

关 键 词：凝胶离心成形 流变性 真空烧结 硬质合金 

分 类 号：TG135.5[一般工业技术—材料科学与工程]