Effects of V and Al on Microstructure and Room Temperature Fracture Toughness of Nb-Si In-situ Composites

来源期刊：稀有金属材料与工程2009年增刊第3期

论文作者：Han Yafang Song Jinxia Qu Shiyu Kang Yongwang

关键词：composite materials; microstructure; room-temperature fracture toughness;

摘    要：The effect of alloying elements V and Al on microstructure and room temperature fracture toughness of an experimental Nb-Si in-situ composite was investigated. The Nb-Si alloys with different amount of V and Al were prepared by non-consumable arc-melting furnace. The experimental results showed that with the addition of V and Al, the microstructure of the Nb-Si materials transformed from Nb_(ss)+Nb_3Si to Nb_(ss)+Nb_5Si_3 and the lattice parameters of Nb_(ss) phase decreased, and the alloying element V promoted the formation of the finer Nb_(ss) structure. It was observed that the room temperature fracture toughness was improved by the addition of V and Al, and the optimum room-temperature fracture toughness of the material appeared in the alloy with 2.6at.%V and 3.6at.%Al. The improvement of room temperature fracture toughness may be mainly attributed to the increment of the volume fraction of Nb_(ss) phase and the decrement of the silicide phase size.