中强高韧钛合金EB熔炼及板材制备

EB Melting and Plate Preparation of Medium Strength and High Toughness Titanium Alloy

采用短流程、低成本的一次EB熔炼方法制备钛合金扁锭,然后通过不经锻造直接进行轧制的工艺方案,获得了700 MPa级20 mm厚的Ti-Al-Mo-V-Zr-Sn成分体系钛合金热轧板,研究了热处理工艺对钛合金板材组织、性能的影响。结果表明:通过EB炉一次熔炼可以获得成分均匀的Ti-Al-Mo-V-Zr-Sn系钛合金扁锭,采用在Tβ相变点附近开坯轧制,并在α+β两相区换向轧制及成品退火热处理的工艺方案,获得了中强高韧钛合金板材,且随着热处理温度升高,钛合金板材冲击韧性提升,在900℃的热处理温度下获得了最佳的强度和韧性匹配,为中强高韧低成本钛合金板材制备提供了可行方案。

Titanium alloy flat ingots are prepared by using a short process,low-cost EB melting method,and then rolled directly without forging to prepare a 700 MPa grade 20 mm thick Ti-Al-Mo-V-Zr-Sn system titanium alloy hot rolled plate.The effect of heat treatment process on the microstructure and properties of the titanium alloy plate is studied.The results show that the Ti-Al-Mo-V-Zr-Sn titanium alloy flat ingots with uniform composition can be obtained through one-time EB melting.The medium strength and high toughness titanium alloy plates can be obtained by rolling at the temperature near the Tβtransus,and reversing rolling theα+βzone and annealing the finished product at the temperature below the Tβtransus.With the increase of heat treatment temperature,the impact toughness of titanium alloy plates is improved.The match between strength and toughness is good when the heat treatment temperature is near the Tβtransus and above 900℃.