Establishing various processing routes and their effect on microstructure and high temperature properties for alloys with melting temperatures >1900°C

建立熔化温度>1900℃合金的各种加工路线及其对显微组织和高温性能的影响

• 批准号: 404942487
• 负责人: Professor Dr.-Ing. Uwe Glatzel
• 金额: --
• 依托单位: National Science and Technology Council (NSTC)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/404942487?language=en
• 关键词: Establishing; various; processing; routes; their

Refractory metal based alloys are generally produced by powder metallurgy. Up to now, little is known about ingot metallurgy produced materials with melting points exceeding 1900°C. The already known methods are only suitable for the fabrication of small sample quantities, or have very limited geometric freedom. Therefore, the aim of this proposal is to improve various ingot metallurgy routes to fabricate alloys with melting points >1900°C. This project will be carried out in close collaboration with Prof. An-Chou Yeh of National Tsing Hua University, Taiwan. In this joint work, the materials of interest include Mo-9Si-8B-2Al (at.%), Cr-7Si-2Ge-2Mo (at.%), and Mo-Al-Ti-based alloys. The work-shares between University Bayreuth and National Tsing Hua University are as follows:University Bayreuth will be responsible of (1) Optimization of the vacuum induction melting process for casting the above mentioned alloys, for sample quantities of up to 2.5 kg. The focus is to achieve a porosity < 1.0 vol.% and to avoid segregations. (2) Microstructural observations at the alloy/crucible interface and alloy center. (3) Comparison of the creep properties of VIM and floating zone (FZ) produced samples at temperatures up to 1700°C in a vacuum tensile creep testing device.National Tsing Hua University will take charge of (1) Optimization of floating zone technique for achieving single crystals with sizes of > 9 mm in diameter and > 40 mm in length. (2) Study the elemental segregations, phase transformations. (3) Determination of oxidation behaviors up to 1700 °C as function of the two production routes, vacuum induction and floating zone melting.

难熔金属基合金通常通过粉末冶金生产。到目前为止，对熔点超过1900°C的铸锭冶金生产的材料知之甚少。已知的方法仅适用于小样品量的制造，或者具有非常有限的几何自由度。因此，本提案的目的是改进各种铸锭冶金路线，以制造熔点>1900°C的合金。该项目将与台湾国立清华大学叶岸洲教授密切合作进行。在这项联合工作中，感兴趣的材料包括Mo-9 Si-8B-2Al（at.%），Cr-7Si-2Ge-2 Mo（原子%），和Mo-Al-Ti基合金。拜罗伊特大学和国立清华大学之间的工作份额如下：拜罗伊特拜罗伊特大学将负责（1）优化铸造上述合金的真空感应熔炼工艺，样品量高达2.5 kg。重点是实现孔隙率< 1.0体积%避免种族隔离。(2)合金/坩埚界面和合金中心的显微组织观察。(3)在真空拉伸蠕变试验装置中，比较Vim和浮区法（FZ）生产的样品在高达1700°C的温度下的蠕变性能。国立清华大学将负责（1）优化浮区法技术，以获得直径> 9 mm、长度> 40 mm的单晶。(2)研究元素偏析，相变。(3)测定高达1700 °C的氧化行为，作为两种生产路线（真空感应和浮区熔炼）的函数。