对金属间化合物Ti2AlNb基合金在加热状态下的变形行为和变形机理进行研究。首先，利用单向拉伸试验得到不同温度和应变速率下合金的真应力?应变关系；然后，通过拉深和弯曲试样得到合金的极限拉深比(LDR)及弯曲性能参数；最后，通过金相实验和断口形貌分析研究Ti2AlNb基合金在不同加热条件下的高温变形机制。结果表明：在750~950°C、应变速率0.001 s?1的条件下，随着温度的升高，合金的伸长率从13.58%增大至97.82%，屈服强度从788 MPa降低至80 MPa；当温度达到950°C时，应变速率对合金的变形性能有明显影响。同时，在该温度范围内，材料发生由O相向B2和α2相的组织转变，从微观组织演变揭示了Ti2AlNb基合金塑性提高的变形机理。
The deformation behavior and mechanism of Ti2AlNb-based alloy were experimentally investigated at elevated temperatures. Firstly, the stress?strain relationships at different temperatures and strain rates were investigated via uniaxial tensile testing. Then, formability data, as determined by examining the deep drawing and bending abilities, were obtained through limiting draw ratio (LDR) and bending tests. Finally, metallographic experiments and fracture morphology investigations were conducted to examine the thermal deformation mechanism of the alloy. The results showed that as the temperature increased, the total elongation increased from 13.58% to 97.82% and the yield strength decreased from 788 to 80 MPa over the temperature range from 750 to 950 °C at a strain rate 0.001 s?1. When the temperature reached 950 °C, the strain rate was found to have a great influence on the deformation properties. The plastic formability of the sheet metal was significantly improved and a microstructuraltransformation of O toB2 andα2 occurred in this temperature region, revealing the deformation mechanism of its plasticity.
参考文献
| [1] | 宋辉;王忠金;赫晓东.高密度脉冲电流处理对Ti2AlNb基合金板材的增塑作用[J].中国有色金属学报（英文版）,2013(1):32-37. |
| [2] | WU Hong-yan;ZHANG Ping-ze;CHEN Wei;WANG Ling;ZHAO Hao-feng;XU Zhong.High-temperature tribological behaviors of Ti_2AlNb-based alloys by plasma surface duplex treatment[J].中国有色金属学报（英文版）,2009(05):1121-1125. |
| [3] | N. V. Kazantseva;S. L. Demakov;A. A. Popov.Microstructure and Plastic Deformation of Orthorhombic Titanium Aluminides Ti_2AlNb. III. Formation of Transformation Twins upon the B2 -> O Phase Transformation[J].The Physics of Metals and Metallography,20074(4):378-387. |
| [4] | 秦春;姚泽坤;李誉之;宁永权;郭鸿镇.热加工对电子束焊接TC11/Ti2AlNb双合金接头组织和性能的影响[J].中国有色金属学报（英文版）,2014(11):3500-3508. |
| [5] | 冯艾寒;李渤渤;沈军.Ti2AlNb基合金的研究进展[J].材料与冶金学报,2011(1):30-38. |
| [6] | L. Germann;D. Banerjee;J.Y. Guedou.Effect of composition on the mechanical properties of newly developed Ti_2AINb-based titanium aluminide[J].Intermetallics,20059(9):920-924. |
| [7] | S.V.Kamat;A.K.Gogia;D.Banerjee.Effect of alloying elements and heat treatment on the fracture toughness of Ti-Al-Nb alloys[J].Acta materialia,19981(1):239-251. |
| [8] | PENG Ji-hua;MAO Yong.Tensile properties and fracture behavior of Ti2AlNb based alloys at room temperature[J].中国有色金属学会会刊,2000(03):378. |
| [9] | Daniel G. Sanders;Mamidala Raniulu.Examination of Superplastic Forming Combined with Diffusion Bonding for Titanium: Perspective from Experience[J].Journal of Materials Engineering and Performance,20046(6):744-752. |
| [10] | S V Sajadifar;G G Yapici;M Ketabchi;B Bemanizadeh.High Temperature Deformation Behavior of 4340 Steel: Activation Energy Calculation and Modeling of Flow Response[J].钢铁研究学报（英文版）,2013(12):133-139. |
| [11] | 徐斌;曾卫东;何德华;周义刚;梁晓波;李世琼.Ti-22Al-25Nb合金热变形行为研究[J].热加工工艺,2007(1):1-4. |
| [12] | 沈军;冯艾寒.Ti2AlNb基合金微观组织调制及热成形研究进展[J].金属学报,2013(11):1286-1294. |
| [13] | 王辉;罗应兵;PeterFRIEDMAN;陈明和;高霖.高强度铝合金7075的温成形性能[J].中国有色金属学报（英文版）,2012(1):1-7. |
| [14] | Peng Lin;Zhubin He;Shijian Yuan.Instability of the O-phase in Ti-22Al-25Nb alloy during elevated-temperature deformation[J].Journal of Alloys and Compounds: An Interdisciplinary Journal of Materials Science and Solid-state Chemistry and Physics,2013:96-102. |
| [15] | 王凯旋;曾卫东;赵永庆;邵一涛;周建华;王晓英;周义刚.钛合金片层α相在热加工过程中演变规律的定量研究[J].稀有金属材料与工程,2010(4):565-569. |
| [16] | J. F. Michel;P. Picart.Size effects on the constitutive behaviour for brass in sheet metal forming[J].Journal of Materials Processing Technology,20033(3):439-446. |
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