热处理对锻态2.5vol.%(TiB TiC)/Ti复合材料组织与性能的影响

Effect of Heat Treatment on the Microstructure and Properties of As Forged 2.5vol.% (TiB TiC)/Ti Composite

摘要:

研究了热处理条件对锻态2.5vol.%(TiB TiC)/Ti复合材料显微组织和力学性能的影响。结果表明：固溶时效处理对复合材料的基体组织特征有显著影响，在两相区进行固溶时效处理后，得到等轴和双态组织，随固溶温度的升高，初生α相含量逐渐降低，而β转变组织含量逐渐升高，当固溶温度超过β转变温度时，得到全片层组织。TiB和TiC增强相在热处理过程中较为稳定，形态与分布无明显变化。固溶时效处理后，锻态复合材料的拉伸强度提高而塑性降低，随固溶温度的升高，复合材料的室温拉伸强度和塑性均有明显增加，而650 oC下拉伸强度与塑性与室温下表现出相反的规律。复合材料经1050oC/2h/AC 600oC/6h/AC处理后综合性能最好，室温拉伸强度为1215.8MPa，延伸率为3.14%，650 oC下拉伸强度为629.9MPa，延伸率为15.9%。

Abstract:

The effects of heat treatment on microstructure and mechanical properties of as forged 2.5vol.%(TiB TiC)/Ti composite have been studied in this paper. The results showed that solution and aging treatments have a significant impact on the matrix characteristics and tensile properties of the composite. Equiaxed, bimodal and fully lamellar microstructures were obtained, the content of primary α reduces while the content of the transformed β phase increases with increasing of solution temperature. The TiB and TiC reinforcements are stable during heat treatment and their morphologies and distribution have no obvious change. The tensile strength increases while the elongation decreases after solution and aging treatment. With increasing of solution temperatures, both the tensile strength and elongation rises at room temperature, while the tensile strength and elongation tested at 650 oC exhibit a contrary tendency. The composite presents superior comprehensive properties with tensile strength of 1215.8MPa and elongation of 3.14% at room temperature, while tensile strength of 629.9MPa and elongation of 15.9% at 650 oC after the heat treatment of 1100 oC/2h/AC 600 oC/6h/AC.