【摘要】 本文通过1100°C/1 h真空热压烧结技术制备了2.6vol%TiBw/Ti6Al4V网状增强钛基复合材料,并建立了热处理参数与各相百分含量的量化关系。结果表明,在固溶温度930～1100°C和时效温度400～600°C之间,各相百分含量与固溶、时效温度呈线性变化。并且经过950°C/1 h固溶处理与600°C/12 h时效处理后,由于热处理过程中发生了静态再结晶,钛基复合材料呈现等轴状。对等轴钛基复合材料进行高温拉伸测试,结果表明,材料高温抗拉强度达到772MPa(400°C),658MPa(500°C),392 MPa(600°C),182 MPa(700°C),高温伸长率也分别为9.1%(400°C), 12.5%(500°C), 28.6%(600°C),35.3%(700°C)。通过对材料高温断口的分析,发现TiB晶须在600°C温度以下能够起到很好的增强效果,但是当温度超过700°C后,TiB晶须与基体发生脱粘现象,导致Ti B晶须的增强效果显著降低,并且使裂纹沿着晶界扩展。更多还原

【Abstract】 In this paper, the 2.6 vol%TiBw/Ti6Al4V composites with network architecture were fabricated by hot press sintering(HPS) at 1100 °C for 1 h, and the quantitative relationships between phases and heat treatment temperatures were established. The results showed that the volume fraction phases changed linearly with a range of solution temperature(930-1010 °C) and aging temperature(400-600 °C). Moreover, the composites with equiaxed microstructure were obtained due to the static recrystallization after solution treated at 950 °C for 1 h and aging treated at 600 °C for 12 h. The ultimate high temperature tensile strengths were 772, 658, 392 and 182 MPa, and the elongations were 9.1%, 12.5%, 28.6% and 35.3% at 400, 500, 600 and 700 °C, respectively. In addition, fractured morphology analysis indicated the excellent strengthening effect of TiBw at a temperature below 600 °C. However, the strengthening effect was significantly reduced due to the debonding of matrix and TiBw at 700 °C and caused the cracks to propagate along the grain boundary.更多还原