| High temperature titanium alloy is an important material which is used in the field of modern aerospace and defense, is also one of the main frontier of titanium alloy. However, about this aspect there is a huge contradiction between the slow process of development and the urgent application needs in our country. So, the depth study of high-temperature titanium alloy is essential. This article mainly aims at above 600℃ Ti-Al-Sn-Zr-Mo-Si-based high temperature titanium alloy. Forming method is precision casting technology which has the advantage of High productivity and good dimensional accuracy. Then, we analyzed and optimized the its various process steps. We thoroughly evaluated casting performance and tested the physical properties parameters of the high temperature titanium alloys. Finally, the article presented a suitable heat treatment process and a casting program.This paper studies performance vary of the investment casting slurrys in different powder-liquid ratio. By flow cup method and digital rotational viscometer, the result showed that the Y2O3 powder and yttrium sol at the ratio of 2.2:1 has a good Tu linked performance relatively. Three-point bending test shows that the most significant firing strength increase is powder-liquid ratio of 2.4:1. This paper also presented Micro Vickers Hardness trend near reaction interface after pouring. The article analysised interaction cross-comparison results between the three kinds of shell and three alloys by using line scanning method. And then, the most suitable combination was selected by evaluating their advantages and disadvantagesThe melting method is water-cooled copper crucible vacuum induction melting technology. It can obtain a uniform and stability composition of multiple titanium alloy ingot. We can obtain smaller grains of α-phase structure by giving cast alloy 2h solution treatment in the vicinity of the β-phase transition point. Then we give the alloy aging treatment at different temperatures or for different times The results show that the high temperature alloy is more sensitive to the aging time after comparing different aging treatment. the room temperature performance of the alloy can improve at 700℃ for 4h, but too long time make performance degraded.The experimental results show bad filling properties and poor fluidity of high temperature titanium alloy by pouring the hexagonal graphite mold casting of different thickness, and helical graphite mold casting. After adding 0.3B, liquidit y reduced by 16.9%. Comparing two typical ladder-type castings by lost wax centrifugal casting and graphite centrifugal casting, the article analyzes advantages and disadvantages of the two mold materials, also reflects the casting properties of the alloy indirectly. At the same time, the paper respectively calculated the free and hindered linear shrinkages in the lost wax method centrifugal casting process, which is 1.323% and 0.653% with microscopy odometryIn this paper, analysis of a complex thin-walled tube used in aerospace field had been carried out. Firstly a complete thermal parameters table of TC4 alloy and Ti-Al-Sn-Zr-Mo-Si-based high temperature titanium alloy will be established by combining measurements and JMat simulation result. And then, it gave us the simulation and optimization of the parts’ structure and the design of gating system and compare different casting process parameters with Anycasting simulation software. After comparing different casting process parameters, the best casting process has been determined which is 1900℃ pouring casting temperature, 250 rpm centrifugal rotation, open-top note gating system, investment casting centrifugal casting method. Finally, it compared the casting characteristics of two titanium alloy and predicted the position of defects occurrence, which could serve as a reference for the actual production. |
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