摘要
Based on the analyses of the microstructures and phase diagrams of the TiAl-based alloy, the relationship among the composition, structure and mechanical properties of the B2-containing y-TiAI alloys was reviewed. The refinement of microstructures and improvement of mechanical properties of TiA1 alloy through stabilization of the β/B2 phase were reviewed. The mechanism of the superplastic behavior of the B2-containing y-TiAI alloys was discussed. With a reasonable addition of β-stabilizer, metastable B2 phase can be maintained, which is favorable for fine-grained structure and better high-temperature deformation behaviors. The mechanical properties of the B2-containing TiAI alloy, including the deformability and elevated temperature properties, can also be improved with doping elements and subsequent hot-working processes. The above mentioned researches discuss a new way for developing TiAI alloys with comprehensive properties, including good deformability and creep resistance.
从合金相的结构与相图入手,探讨了B2型TiAl基合金(以γ相为基、含β/B2相的TiAl合金)成分、结构、组织与性能的相关性,分析了β/B2相细化合金的组织和提高材料的高温变形能力的原因,并阐述了B2型TiAl基合金超塑性变形的机理。在TiAl基合金中添加适量的β稳定型元素,形成较稳定的B2结构的有序相,有利于细化晶粒和提高材料的高温变形能力。这种B2型TiAl基合金可通过掺杂微量低序数元素以及随后的热加工工艺提高其综合性能,包括变形能力和高温性能。
基金
Project (2011CB605505) supported by the National Basic Research Program of China
Project (2011JQ002) supported by the Fundamental Research Funds for the Central Universities, China
