α+β两相型钛合金TC4低成本制备及防护性能研究

Low Cost Preparation and Protective Properties ofα+βTwo-Phase Titanium Alloy TC4

α+β两相型钛合金TC4综合性能优良,本研究旨在针对装甲防护领域提供低成本高防护性能的TC4钛合金。采用电子束(electron beam,EB)冷床炉熔炼+真空自耗熔炼(vacuum arc remelting,VAR)工艺,降低TC4生产制备成本;采用两种热加工工艺调控靶板的显微组织,对不同组织和厚度的靶板进行防护性能测试、弹坑显微组织观察、靶板失效分析,确定获得具有优异防护性能的TC4合金靶板的热加工工艺。结果表明:EB+VAR熔炼工艺在保证高均质TC4铸锭的前提下,实现成本降低约20%~30%;通过高韧性热加工工艺:T_(β)+30℃单相区开坯轧制,后在T_(β)-15℃两相区较高温度二火轧制,再进行800℃退火1 h+空冷,获得双态组织,此组织状态TC4靶板防护性能最优。

TC4 alpha+beta two-phase titanium alloy has excellent comprehensive properties.This study aims to provide low-cost highly-protective TC4 titanium alloy for armor protection applications.Electron beam(EB)cold bed furnace melting+vacuum arc remelting(VAR)process is used to reduce the production and preparation cost of TC4.The microstructure of the target plate is regulated by two kind of heat treatment processes,and the protective performance,microstructure of the bullet crater,and failure analysis of the target plate with different microstructures and thicknesses are tested,to determine the optimal heat treatment process for obtaining excellent protective performance of the TC4 alloy target plate.The results show that the EB+VAR melting process achieves a cost reduction of about 20%to 30%while ensuring high homogeneity of TC4 ingots;through high toughness hot processing technology:billet rolling at T_(β)+30℃single-phase zone,followed by two fire rolling at T_(β)-15℃high-temperature point of two-phase zone,and then annealing at 800℃for 1 hour+air cooling,a dual state microstructure is obtained.This dual microstructure state has the best protective performance for TC4 target plate.