Nb-Ti-Cr-Si基超高温合金的室温断裂韧性研究进展

摘要

Nb-Ti-Cr-Si基超高温合金具有良好的高温强度和高温抗氧化性能，但室温断裂韧性较差。为了提高该合金的室温断裂韧性，分析了该合金室温断裂韧性较低的原因，对有坩埚整体定向凝固技术、整体定向凝固＋高温均匀化处理和热压烧结法等工艺对Nb-Ti-Cr-Si基超高温合金的室温断裂韧性的影响做了评述，指出了提高该合金室温断裂韧性将来努力的方向。%Nb-Ti-Cr-Si based ultrahigh temperature alloy possesses good high temperature strength and high temperature oxidation resistance,but its room temperature fracture toughness is poor.In order to improve room tem-perature fracture toughness,the reason of poor room temperature fracture toughness are discussed,and the effects of integrally directional solidification with the use of a crucible,directional solidification after homogenization treatment and hot press technologies on the room temperature fracture toughness of Nb-Ti-Cr-Si based ultrahigh temperature al-loy are reviewed.Finally,the future direction to regarding room temperature fracture toughness of these alloy are pro-posed.