(1. 太原理工大學 先進鎂基材料山西省重點實驗室，太原 030024；
2. 哈爾濱工業(yè)大學 金屬精密熱加工國家級重點實驗室，哈爾濱 150001)
摘 要: 采用真空感應熔煉技術(shù)制備不同體積分數(shù)(TiBw+TiCp)/Ti復合材料，研究該系列復合材料在600~750 ℃高溫拉伸力學行為。結(jié)果表明：(TiBw+TiCp)含量由0增加到7.5%(體積分數(shù))時，(TiBw+TiCp)/Ti復合材料基體初始β晶粒和α片層得到顯著細化；TiBw及TiCp的原位生成顯著提高了基體合金的抗拉強度，并隨(TiBw+TiCp)體積分數(shù)的增大而增大；隨著拉伸溫度升高，(TiBw+TiCp)/Ti復合材料抗拉強度降低而塑性增加，TiBw及TiCp對基體的強化作用主要源于細晶強化、載荷傳遞強化；(TiBw+TiCp)/Ti復合材料在600~700 ℃的斷裂機制為TiBw和TiCp的斷裂在750 ℃為增強相與基體間界面脫粘。
關(guān)鍵字: 鈦基復合材料；顯微組織；高溫拉伸性能；失效機理
（1. Shanxi Key Laboratory of Advanced Magnesium-based Materials, Taiyuan University of Technology, Taiyuan 030024;
2. National Key Laboratory for Precision Hot Forming of Metals, Harbin Institute of Technology, Harbin 150001）
Abstract:Titanium matrix composites reinforced with different volume fractions of (TiBw+TiCp) were prepared by vacuum induction melting technology, the high temperature tensile mechanical behavior of (TiBw+TiCp)/Ti composites at 600~750 ℃ was investigated. The results indicate that the prior β grain size and α lath width are gradually refined with the (TiBw+TiCp)/Ti (volume fraction) increasing from 0 to 7.5%. The in situ TiBw and TiCp can improve the ultimate tensile strengths of the matrix alloy significantly, and then increase with the increase of (TiBw+TiCp) volume fraction. With the increase of the tensile temperature, the ultimate tensile strength decreases while the elongation increases. The strengthening effects of (TiBw+TiCp) on matrix alloy are mainly attributed to the grain refinement, load transfer and solid solution of C. The fractograph characteristic of the composites reveals that fracture of TiBw and TiCp is the main failure mechanism of the composites at 600-700 ℃ while interfacial debonding dominates the fracture mechanism of the composites at 750 ℃.
Key words: titanium matrix composite; microstructure; high temperature tensile property; failure mechanism
