摘要
以TiH2粉末为原料,通过组元球磨混合、压制成形和烧结工艺制备钛合金。用扫描电镜对球磨过程TiH2粉末的粒度、形貌变化以及烧结CP-Ti,Ti-6Al-4V合金的组织形貌进行了观察;采用热重分析方法研究了TiH2粉末脱氢的特性;用热膨胀技术研究了TiH2,TiH2-Al-V两种粉末压坯的烧结致密化特性。结果表明:TiH2粉末经过球磨后迅速变细,其粒度随球磨时间的延长而减小,粉末形貌由原来的不规则形状逐渐变为等轴状;TiH2粉末在烧结过程的脱氢将使α-Ti产生强烈收缩、同时因脱氢后获得的新鲜钛表面所发生的快速粘接而使烧结体迅速致密、得到相对密度大于99%的烧结坯体;TiH2-Al-V粉末压坯在烧结时因为伴随着合金元素的溶解而使其烧结致密特性不如纯TiH2粉末压坯的好;TiH2粉末经过成型、烧结脱氢工艺可获得典型的等轴状纯钛组织,TiH2-Al-V粉末经过相同工艺可获得典型的层片状α+β钛合金组织、且合金元素分布均匀。
The titanium hydride was directly used as the raw material through component mixing, compaction and sintering to manufacture the titanium alloy. The particle size and morphology of Till2 change with the milling process and the mierostructure of CP-Ti and Ti-6A1-4V alloy were observed u- sing scanning electron microscope. The dehydrogenation characteristics of Till2 powder was studied using thermal gravimetric analysis. The thermal expansion technique was used to evaluate the sinte- ring densification characteristics of compacts of Till2 and TiH2-A1-V powder. The results show that the particle size of Till2 powder after ball milling is reduced rapidly with ball milling time adding and the powder morphology change gradually from the original irregular to be the equiaxed. The compacts of TiHe powders is easy to sintering densification due to the combination of dehydrogenation and shrinkage of ^-Ti in the process, which creates the fresh dehydrogenation titanium uniform during sin- tering, thus leads to rapid densification and very high sintering relative density, higher than 99%. In contrast, it is difficult to achieve a full densification of TiH2-A1-V alloy powder during sintering process, which requires dissolution of alloy elements. The microstructure of sintered sample of Till2 powders compacts appears typical pure titanium with equiaxed. The microstructure of TiH2-A1-V alloy shows the typical lamellar like α＋β characteristics with a uniform distribution of alloy element.
出处
《材料工程》
EI
CAS
CSCD
北大核心
2013年第10期64-70,共7页
Journal of Materials Engineering
关键词
粉末冶金
TiH2
球磨
成型
烧结
脱氢
显微组织
powder metallurgy
Till2
ball milling
forming ~ sintering
dehydrogenation
microstructure
