High temperature mechanical behavior of advanced directionally solidified multi-phase Mo-alloys with and without coating (HTMA-DS Mo)

带涂层和不带涂层的先进定向凝固多相钼合金的高温机械性能（HTMA-DS Mo）

• 批准号: 438070774
• 负责人: Professorin Dr.-Ing. Manja Krüger
• 金额: --
• 依托单位: Institut für Werkstoff- und Fügetechnik (IWF)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/438070774?language=en
• 关键词: temperature; mechanical; behavior; advanced; directionally

Mo-Hf-B and Mo-Zr-B alloys as a new class of refractory alloys are potential candidates in stationary and mobile turbine applications. Due to the high melting points of the constituents high-temperature strength and creep strength are expected up to 1,400 °C. Those high service temperatures, in turn, may result in higher turbine efficiencies and may reduce primary energy consumption.As a manufacturing route, directional solidification via zone melting as a new processing approach for Mo-Hf-B and Mo-Zr-B results in low oxygen (< 50 ppm) impurities, which is essential to avoid embrittlement of these alloys; moreover the materials possess a homogeneous fibre-reinforced microstructure.Aim of this proposal is to investigate the high-temperature creep behaviour of this novel class of refractory alloys to qualify them for high-temperature applications. While creep test data are available from experiments under compression, no data of creep under tensile load and under real service conditions are available for this type of alloys. Thus, our experimental research will divide into three parts: i) Sample preparation via directional solidification in a zone melting process, carried out at Kiev Polytechnical Institute KPI, and microstructure and phase composition characterization of the fibre-reinforced Mo-Hf-B and Mo-Zr-B alloys at KPI and at the Otto-von-Guericke University, Magdeburg, OVGU. ii) Creep tests will be carried out at OVGU under inert atmosphere and under real service conditions. For the later an oxidation protection coating must be provided due to oxidation and evaporation of molybdenum from the alloys. For this, iii) an oxidation protection coating strategy will be developed based on particle loaded preceramic polymers, and tensile creep behaviour will be characterized for coated alloys in oxidizing atmosphere. From these results we will a) develop a creep model for this novel-type material class and b) a coating model for molybdenum based refractory alloys.

Mo-Hf-B 和 Mo-Zr-B 合金作为一种新型难熔合金，是固定式和移动式涡轮机应用的潜在候选者。由于成分的高熔点，预计高温强度和蠕变强度可达 1,400 °C。这些高工作温度反过来可能会导致更高的涡轮机效率，并可能减少一次能源消耗。作为一种制造路线，通过区域熔化进行定向凝固作为 Mo-Hf-B 和 Mo-Zr-B 的新加工方法，可产生低氧 (< 50 ppm) 杂质，这对于避免这些合金脆化至关重要；此外，该材料具有均匀的纤维增强微观结构。该提案的目的是研究此类新型耐火合金的高温蠕变行为，以使其适合高温应用。虽然蠕变测试数据可从压缩实验中获得，但对于此类合金，没有拉伸载荷下和实际使用条件下的蠕变数据。因此，我们的实验研究将分为三个部分：i）在基辅理工学院 KPI 进行的区域熔化过程定向凝固样品制备，以及 KPI 和 OVGU 马格德堡奥托冯格里克大学的纤维增强 Mo-Hf-B 和 Mo-Zr-B 合金的微观结构和相组成表征。 ii) 蠕变试验将在 OVGU 惰性气氛下和实际使用条件下进行。对于后者，由于合金中钼的氧化和蒸发，必须提供氧化保护涂层。为此，iii) 将基于颗粒负载陶瓷前体聚合物开发氧化保护涂层策略，并且将表征氧化气氛中涂层合金的拉伸蠕变行为。根据这些结果，我们将 a) 开发这种新型材料类别的蠕变模型，b) 钼基耐火合金的涂层模型。