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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…

Monocrystalline materials occupy a core position in high-tech industries such as semiconductors, optoelectronics, lasers, and aerospace, and their crystal quality directly affects the performance and reliability of terminal devices. In order to obtain high-purity, high-consistency, and high-defect controlled single crystal materials, crystals need to be grown in extreme temperatures and highly controllable environments. In the whole single crystal preparation system, tungsten crucible has become an irreplaceable key component due to its unique physical and chemical properties. It not only plays…

In a vacuum furnace environment, where the atmosphere is clean and the oxygen content is very low, metal materials need to have high heat resistance, evaporation resistance and structural stability. With its unique properties, tungsten crucible plays an irreplaceable role in high-temperature precision processes including aerospace, semiconductors, special alloys, rare earth metallurgy, etc. In this paper, the high temperature resistance of the crucible in vacuum furnace will be systematically analyzed from the aspects of thermal stability, sublimation resistance, heat conduction…

The development of high-end manufacturing industry has put forward higher requirements for the temperature resistance, thermal shock resistance, structural stability and service life of tungsten crucibles. In order to better meet various extreme working conditions, the performance optimization of crucibles has become an important topic in manufacturing and application. The following will discuss the performance optimization path of crucibles from the aspects of raw material selection, densification process, microstructure control, surface modification and composite materials. 1. Use high-purity tungsten powder…

The manufacturing process of tungsten crucible is complex and the technical requirements are high, mainly including powder preparation, pressing molding, high-temperature sintering and mechanical processing. 1. Preparation of raw materials The manufacture of crucibles begins with the preparation of high-purity tungsten powder. Tungsten powder is usually obtained by hydrogen reduction of tungstate, such as sodium tungstate or ammonium tungstate. High-quality crucibles have extremely high requirements for the purity of raw materials, usually requiring tungsten powder purity of more than 99.95%…