Effect of hydrogen on superplastic deformation of (TiB + TiC)/Ti–6Al–4V composite
Effect of hydrogen on superplastic deformation of (TiB + TiC)/Ti–6Al–4V composite
复制标题
DOI：
10.1016/j.ijhydene.2009.07.091
复制
发表时间：
2009-10
影响因子：
7.2
通讯作者：
Junqiang Lu;J. Qin;W. Lu;Yifei Chen;Di Zhang;H. Hou
中科院分区：
文献类型：
--
作者：
Junqiang Lu;J. Qin;W. Lu;Yifei Chen;Di Zhang;H. Hou
制备了TiB + TiC增强Ti-6Al-4V基复合材料，并对其进行了氢化处理。通过X射线衍射（XRD）鉴定物相。通过光学显微镜（OM）检查微观结构。测定了复合材料的转变温度与氢浓度的关系。结果表明，氢气使复合材料的相变温度显著降低，β相含量增加。对氢化复合材料进行了超塑性变形。氢降低了合金的最佳超塑性温度，提高了最佳超塑性应变速率。氢化复合材料的流动应力比未氢化复合材料有很大的降低。复合材料的应变速率敏感性指数m随氢含量的增加而增大，在氢含量为0.85wt.%时达到最大值0.327 H.活化能Q随氢浓度的增加而减小，在488- 382 kJ/mol之间。氢在超塑性变形过程中促进了复合材料的再结晶，细化了组织。
Ti–6Al–4V matrix composite reinforced with TiB plus TiC was prepared and hydrogenated. The phases were identified by X-ray diffraction (XRD). Microstructures were examined by optical microscopy (OM). Dependence of transus temperatures of the composite on hydrogen concentration was determined. The result shows hydrogen decreases transus temperatures of the composite significantly and increases the amount of β phase. Superplastic deformation of the hydrogenated composites was performed. Hydrogen decreases the optimum superplastic temperatures and increases the optimum superplastic strain rate. The flow stresses of hydrogenated composites decrease greatly compared to unhydrogenated composite. The strain rate sensitivity index m of the composite increases with increasing hydrogen concentration and reaches maximum 0.327 at 0.85wt.% H. Meanwhile, the activation energy Q decreases with increasing hydrogen concentration and ranges in 488–382kJ/mol. Hydrogen promotes recrystallization of the composite and refines the microstructure during superplastic deformation.