3D网状结构TiBw/Ti60复合材料高温力学性能

利用反应热压技术制备了3D网状结构Ti Bw/Ti60复合材料,对复合材料在600~750℃范围内的高温力学性能进行了测试。结果表明,与Ti60合金相比,3D网状结构Ti Bw的原位形成显著提高了复合材料高温强度。在600、650、700和750℃,5.1%(体积分数)Ti Bw/Ti60复合材料的抗拉强度相比Ti60合金分别提高了42.5%、39.9%、35%和13.2%,而延伸率在各温度下均低于基体合金。网状结构复合材料断裂时形成的主裂纹沿网状界面处扩展,且断裂机制随实验温度增加而改变。     

TiB_w/TC4钛合金与C/C复合材料钎焊接头的界面组织结构

采用活性钎料TiZrNiCu对TiBw/TC4钛合金和C/C复合材料进行了钎焊连接,借助SEM,EDS,XRD等分析手段研究了钎焊工艺参数对接头界面组织结构的影响.结果表明,采用TiZrNiCu钎料可以实现对两种材料的连接,接头典型的界面结构为：C/C复合材料/TiC＋（Ti,Zr）2（Cu,Ni）/Ti（s,s）＋（...     

选区激光熔化3D打印钛合金及其复合材料研究进展

选区激光熔化(SLM)3D打印技术作为近年来快速兴起的增材制造技术,在航空航天、国防和生物医疗用高性能钛合金及其复合材料关键及复杂结构件方面具有显著优势、发展潜力巨大.SLM 3D钛合金晶粒细小且常含有大量的α′马氏体,而SLM 3D钛基复合材料中则通常可以原位生成纳米尺度的TiBw和TiCp等陶瓷增强相,使得成形构件的力学性能显著优于铸件和粉末冶金制品水平.本文在介绍SLM 3D打印技术的原理与特点基础上,着重评述了其在钛合金及其复合材料的应用基础研究及工程应用进展,并对未来相关关键基础科学与技术问题进行了展望.     

Influence of TiBw volume fraction on microstructure and high-temperature properties of in situ TiBw/Ti6Al4V composites with TiBw columnar reinforced structure fabricated by pre-sintering and canned extrusion

Tailoring TiBw volume fraction was utilized in TiBw/Ti6Al4V composites to pursue performance optimization for potential high-temperature applications. Detailed investigations focused on the influence of TiBw volume fraction on microstructure and its correlations with mechanical properties mainly at high temperatures ranging from 500 °C to 700 °C. Highly aligned TiB whiskers along extrusion direction caused the formation of TiBw columnar reinforced structure, which was composed of ductile TiBw-poor interior regions and hardened TiBw-rich boundaries. Refined prior β phases arising from dynamic recrystallization led to the size reduction in α colonies. This tendency commonly accompanied with the formation of equiaxed α phase was evidently enhanced by the restriction of increasing TiB whiskers at the boundaries. Much better strengthening of TiB whiskers was achieved on the premise of good interfacial bonding with Ti matrix at high temperatures, and the strengthening depended linearly on their volume fractions, with strength increments of about 44.3 MPa/vol.% at 500 °C, and 27.5 MPa/vol.% at 600 °C, yet merely 6.3 MPa/vol.% at 700 °C. Attributed to the softening of Ti matrix and the crack retardation of ductile TiBw-poor regions by raising temperature, enhanced ductility was negatively correlated with TiBw volume fraction below 600 °C, but positively at 700 °C under the possible grain boundary sliding inspired by ample equiaxed α phase.