鈮坩堝
High melting point: The melting point of niobium is as high as 2468℃, which enables niobium crucibles to maintain a stable physical form in very high temperature environments, not easy to melt and deform, and suitable for high-temperature smelting and other processes. For example, in some experiments or industrial production where metals need to be heated to 1500℃ or even higher, niobium crucibles can reliably carry materials for heating operations.
Good corrosion resistance: Niobium exhibits excellent corrosion resistance in many chemical media. For common acids, such as hydrochloric acid and sulfuric acid within a certain concentration and temperature range, niobium crucibles are basically not corroded. In the production process of some chemical products, high-temperature treatment of corrosive materials is involved. Niobium crucibles can resist corrosion and ensure the smooth progress of the production process and the quality of the product is not contaminated by the crucible material.
Low aspiration: In a high temperature environment, the niobium crucible has a very low adsorption of gas. In the smelting process of semiconductor materials, a pure environment with almost no interference from oxygen and other gases is required to ensure the purity and performance of the materials. The low aspiration characteristic of niobium crucibles is particularly important, which can avoid the contamination of materials due to aspiration.
Good processing performance: Compared with some refractory metals, niobium has relatively good processing performance. It can be processed into crucibles of various shapes and specifications through forging, rolling, welding and other processes to meet the needs of different users and application scenarios. For example, niobium materials can be processed into small crucibles of customized specifications according to the special size requirements of experimental equipment; large niobium crucibles can also be manufactured for large-scale industrial production.
2. Uses of niobium crucibles
Metallurgical industry:
High temperature smelting: used to smelt some rare metals and alloys, such astitanium-alloy.html> titanium alloys, zirconium alloys, etc. The smelting temperature of these alloys is usually high. Niobium crucibles can withstand high temperatures and do not react with the smelted metals, ensuring the precise control and purity of the alloy composition. In the manufacture of high-performance titanium alloys used in the aerospace field, niobium crucibles are used in high-temperature smelting to ensure that the quality of the alloy meets stringent requirements.
Purifying metals: Using the high melting point and corrosion resistance of niobium crucibles, metals are purified by specific physical or chemical methods at high temperatures. For example, when purifying tantalum metal, the impure tantalum raw material can be placed in a niobium crucible, and the impurities can be volatilized or removed by chemical reaction under high temperature and vacuum environment, so as to obtain high-purity tantalum.
Electronic industry:
Preparation of semiconductor materials: In the process of growing semiconductor single crystals, such as growing silicon single crystals for chip manufacturing, niobium crucibles can be used as containers for silicon melt. Its low gas absorption ensures that the silicon melt is not contaminated by gas at high temperature, so as to grow high-quality and high-purity semiconductor crystals, which is crucial to improving chip performance and yield.
Electronic component manufacturing: In the process of manufacturing some high-end electronic components, such as capacitors and resistors, the composition and microstructure of the materials need to be precisely controlled. Niobium crucibles can be used to melt and process special alloy materials required for these electronic components to ensure the consistency and stability of component performance.
Research field:
Material science research: In experiments on new high-temperature materials, superconducting materials, etc., researchers often need to synthesize, melt and perform performance tests on materials under extreme conditions such as high temperature and high vacuum. Niobium crucibles can provide a stable experimental environment to meet these demanding experimental requirements. In the experiment of exploring new superconducting materials, a variety of metal raw materials are placed in a niobium crucible in a specific proportion, and reacted under high temperature, high pressure and high vacuum environment to study the relationship between the superconducting properties of the material and the composition and preparation conditions.
Physical and chemical experiments: In some high-temperature physical and chemical experiments, it is necessary to accurately measure and control parameters such as reaction temperature and pressure. As a reaction vessel, the good thermal and chemical stability of niobium crucibles contribute to the accuracy and repeatability of experimental data. For example, in experiments studying the kinetics of high-temperature chemical reactions, niobium crucibles can remain stable during long-term high-temperature reactions, allowing researchers to accurately obtain key data such as reaction rates.
III. Niobium crucible grades
Nb1: This is a relatively common pure niobium grade with a purity generally above 99%. Nb1 grade niobium crucibles have good comprehensive performance and are suitable for general industrial applications and some scientific research experiments that do not require extreme purity of the crucible but require the basic properties of niobium materials. In some common rare metal smelting plants, Nb1 grade niobium crucibles are used for daily production, which can meet production needs and have good economic efficiency.
Nb2: The purity is relatively higher, up to about 99.5%. Nb2 grade niobium crucibles are widely used in the electronics industry and some scientific research fields with strict requirements on impurity content. Due to its higher purity, in the preparation of semiconductor materials, it can better ensure that materials such as silicon melt are not contaminated by impurities in the crucible, thereby producing higher quality semiconductor products.
Niobium alloy crucible grades with added alloy elements: In order to further improve certain properties of niobium crucibles, such as improving strength and thermal shock resistance, a small amount of other alloy elements will be added to niobium to form an alloy. Common alloying elements include zirconium (Zr), titanium (Ti), etc. For example, Nb-Zr alloy crucibles containing a small amount of zirconium have improved strength compared to pure niobium crucibles, and perform better in some high-temperature application scenarios that need to withstand large mechanical stress or thermal stress. In some industrial production lines with continuous high-temperature smelting, Nb-Zr alloy crucibles can withstand the thermal stress during frequent heating and cooling due to their high strength, and have a relatively longer service life.
