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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%…

Vacuum heat treatment is a process of heating and cooling metals or alloys under high vacuum or protective atmosphere, and is often used to improve the mechanical properties, dimensional stability and surface quality of materials. Compared with traditional heat treatment methods, it has significant advantages, such as preventing oxidation and decarburization, improving treatment cleanliness, reducing heat treatment deformation, etc., so it is widely used in aerospace, precision instruments, mold manufacturing and high-end electronics industry. As a key component for carrying…

In the field of modern high-end manufacturing, superalloys are widely used in aerospace, gas turbines, nuclear industry and high-temperature chemical industries due to their excellent high-temperature strength, oxidation resistance and corrosion resistance. In order to prepare superalloy materials with excellent properties, uniform structure and stable composition, processes such as melting, alloying, casting and refining are often required at extremely high temperatures. Tungsten crucible, as a metal container with extremely high melting point and excellent chemical stability, has become an indispensable…

With the continuous development of nuclear energy technology, the requirements for thermal stability, corrosion resistance and structural integrity of materials under extreme conditions are increasing, and tungsten crucibles have become one of the important containers for the processing and research of highly radioactive materials, molten nuclear fuel, high-temperature structural materials and radioactive waste due to their excellent physical and chemical properties. First of all, tungsten is characterized by its extremely high melting point of 3410°C, which is one of the…

With the rapid development of semiconductor technology, the requirements for material purity, structural stability and preparation process are increasing. Due to its excellent physical and chemical properties, tungsten crucible occupies an extremely important position in the preparation of semiconductor materials, especially in key processes such as high-temperature crystal growth, smelting, and vapor deposition. Tungsten is a metal with an ultra-high melting point of up to 3410°C, second only to tantalum and rhenium among all metals. This allows the W crucible…