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In the field of advanced materials, tungsten niobium alloy, a typical refractory metal composite, is gaining prominence as a critical foundational material in strategic sectors such as aerospace and high-end equipment manufacturing. This two-phase alloy system, composed of tungsten and niobium, achieves a complementary balance of tungsten’s high melting point and strength with niobium’s excellent ductility and corrosion resistance through elemental ratio control and microstructural design. Known as Tungsten Niobium Alloy or Niobium Tungsten Alloy, it demonstrates irreplaceable value in…

Tungsten crucibles operating in high-temperature environments must have good thermal stability and thermomechanical compatibility, especially when used with other structural materials (such as graphite, ceramic, quartz glass), and its coefficient of thermal expansion (CTE) becomes a key factor in the design and use process. The coefficient of thermal expansion of tungsten in the range of room temperature to 2500°C is roughly between 4.5 × 10??/K and 5.5 × 10??/K, which is much lower than that of general metals such as…

As an important refractory metal product in the field of high temperature, tungsten crucible plays a key role in the fields of metallurgy, semiconductor, aerospace and nuclear energy. In order to ensure its reliability and safety in extreme environments, it is particularly important to test and analyze the mechanical properties of the system. The mechanical properties of W crucible not only determine its structural stability during use, but also directly affect its thermal shock resistance, crack propagation resistance and long-term…

Superalloy is a kind of alloy material that can maintain excellent mechanical properties and corrosion resistance in a high-temperature environment, and is widely used in aerospace, gas turbine, nuclear energy equipment and other fields. Due to the generally high melting point of superalloys, some even exceeding 1500 °C, the preparation process puts forward extremely strict requirements for the high temperature resistance, chemical stability and structural strength of the container material. Tungsten crucible, as one of the most commonly used ultra-high…

Although tungsten has excellent material properties as a high melting point metal, its actual performance in high temperature and extreme environments is also profoundly affected by the microstructure of the material. Therefore, it is of great significance to study the relationship between the microstructure and its properties of tungsten crucible to improve its overall reliability and life. First, microstructure characteristics of W crucible W crucibles are usually manufactured by powder metallurgy process, and their microstructure mainly includes grain morphology, grain…

In some special high-temperature atmospheres or melt environments, tungsten crucibles still face a certain degree of corrosion problems. Corrosion not only affects the service life of the crucible, but can also contaminate the material being treated and reduce product quality. Therefore, improving the corrosion resistance of the crucible is the key to improving its comprehensive performance and prolonging the service life. In this paper, the corrosion mechanism, influencing factors and main improvement methods are systematically analyzed and discussed. 1. The…

Due to the high melting point of tungsten itself, it is difficult for the traditional casting and molding method to be directly applied to the manufacture of crucibles, so the sintering process has become one of the main methods for preparing tungsten crucible. In this paper, we will focus on the sintering process of crucibles, and discuss its process flow, key parameters, technical challenges and optimization directions. 1. Preparation and molding of raw materials before sintering The first step in…