Re和C掺杂TaWHf合金的高温力学性能

High-Temperature Mechanical Properties of TaWHf Alloy Doped with Re and C

摘要:

研究了掺杂Re (1wt%)和C (0.01wt%)的Ta-8W-2Hf合金在室温、1300 ℃和1500 ℃下的高温力学性能。结果表明，再结晶后的TaWHfReC合金中含有细小的弥散析出相Ta₂C，显著提高了合金的力学性能。在1300和1500 ℃的高温下，TaWHfReC合金的强度远高于TaWHf合金。在1300 ℃时，TaWHf合金的抗拉伸强度为322 MPa，而TaWHfReC合金的抗拉伸强度达到了392 MPa。当温度升至1500 ℃时，析出相强化在TaWHfReC合金中仍然有效，其抗拉伸强度达到268 MPa。此外，在1300 ℃下，TaWHfReC合金的延伸率为23.5%，几乎是TaWHf合金的两倍。TaWHfReC合金在高温下力学性能的显著提升主要归因于位错与细小的Ta₂C析出相之间的相互作用。细小且弥散的颗粒有效抑制了位错的运动，并在高温下表现出显著的强化效果。

Abstract:

The high-temperature mechanical properties of Ta-8W-2Hf alloy doped with Re (1wt%) and C (0.01wt%) were investigated at room temperature, 1300 °C, and 1500 °C. Results show that fine and dispersed precipitates Ta₂C are detected in crystallized TaWHfReC alloy, which significantly enhance mechanical properties of the alloy. The strength of TaWHfReC alloy is much higher than that of TaWHf alloy, especially at 1300 and 1500 °C. At 1300 °C, the ultimate tensile strength of the TaWHf alloy is 322 MPa, while that of the TaWHfReC alloy reaches 392 MPa. When the temperature rises to 1500 °C, precipitated-phase strengthening remains effective in the TaWHfReC alloy, achieving an ultimate tensile strength of 268 MPa. Additionally, at 1300 °C, the elongation of the TaWHfReC alloy reaches 23.5%, which is nearly twice of that of the TaWHf alloy. The significant improvement in the mechanical properties of the TaWHfReC alloy at elevated temperatures is primarily attributed to the interaction between dislocations and the fine Ta₂C precipitated phase. The fine and uniformly distributed particles effectively inhibit dislocation motion and exhibit a pronounced strengthening effect at high temperatures.