摘要
以B4C、SiC粗粉为原料,采用机械合金化制备高活性的B4C-SiC超细复合粉体。通过XRD、SEM、LPSA和IR等测试技术研究球料比、过程控制剂及球磨时间对复合粉体性能的影响,确定机械合金化制备B4C-SiC超细复合粉体的最佳工艺条件,研究机械合金化过程中粉体有序-无序转变过程。随后,采用热压烧结工艺验证复合粉体的烧结活性。结果表明:球磨机转速是250 r/min的条件下,球料比为30:1,过程控制剂为2wt%,球磨时间为120 h时,可获得晶格无序的B4C-50wt%SiC超细复合粉体;该复合粉体在1900℃,30 MPa热压条件下烧结1 h,其体积密度为2.62 g/cm3,达到理论密度的93%,比普通混合粉体在相同热压条件下获得样品的致密度提高了8.1%;机械合金化工艺制备的B4C-SiC超细复合粉体具有极高的烧结活性。
High active and ultrafine B4C-SiC composite powders were prepared by the coarse powders of B4C and SiC through the technology of mechanical alloying. Under testing techniques of X-ray diffraction, scanning electron mi- croscope, laser particle size analysis and infrared absorption spectrum, by which studied the influences of ball to pow- der weight ratio, process control agents and milling time on composite powders, the best technological conditions of MA for preparing B4C-SiC ultrafine composite powders could be confirmed. After studying order-disorder transforma- tion of the composite powders during the process of MA, hot pressing sintering was adopted to verify the sintering ac- tivity of the composite powders. The results indicate that the lattice unordered BaC-50wt% SiC ultrafine composite powders can be obtained when the ball to powder weight ratio is 30：1, process control agents 2wt%, milling time 120 h and the rotation speed 250 r/rain. While the composite powders are sintered at 1900℃ with pressure of 30 MPa, the density of samples is 2.62 g/cm3 and the relative density of samples attains 93%. The relative density of samples sintered with the composite powders is 8.1% higher than that of samples sintered with ordinary mixing powders. B4C-SiC ultrafine composite powders prepared by mechanical alloying possess extremely high sintering activity.
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
2014年第2期185-190,共6页
Journal of Inorganic Materials
基金
中日韩A3前瞻计划(51161140399)
武汉理工大学自主创新研究基金(13664302)~~
