High Energy Explosive Loading Spraying Micron Tungsten Powder Technology

Tungsten coating is mainly used in aviation, aerospace, nuclear power, machinery and other industrial fields, and the key parts of friction and movement parts wear protection.
 
explosive loading of micron tungsten powder image
 
Tungsten coating is difficult to prepare because of its special properties. The basic process of high explosive loading spraying technology can be divided into three stages: 1. The use of explosive detonator is paved on the surface of the powder coating with explosives, explosive detonation wave propagation in detonation, similar to slip in explosive welding of detonation wave, high temperature and high pressure of the detonation product formation; 2. The powder of flying coating moves rapidly downward under the action of detonation wave and detonation products with high speed expansion, which can reach a higher speed. By selecting the type of explosive reasonably, controlling the distance between coating powder and matrix, the target velocity of coating powder can be controlled effectively, and the best velocity domain combined with substrate can be achieved; 3. Plate powder combined with heating and accelerating coating powder particles and matrix high-speed collision, through the larger plastic deformation or thermal fusion, the two are firmly combined together.
 
Some scholars try to use high-energy explosive spray preparation of tungsten coating to micron tungsten powder as raw material, the use of black baskets of this base explosive pressure packing column, the pillar size φ 50 mm × 50 mm, the burst speed 8200 m / s, the substrate is 2A12 aluminum, dimensions φ 300 mm × 5 mm. The tungsten powder has a particle size of 5 to 10 um, a purity of 99. 98% and a mass of 150 g. In order to ensure that the tungsten powder has a higher plate speed, so set the fried height of 750 mm and 400mm. Before spraying the surface of the aluminum plate grinding treatment, so that the surface has a certain degree of roughness, can improve the surface area of aluminum, is conducive to the combination with the tungsten powder. 
 
During explosive spraying, the shock wave and detonation product formed by explosive explosion drive the tungsten powder into the aluminum plate at high speed, and serious plastic deformation occurs between the aluminum plate and tungsten powder, forming mechanical bite, and finally forming a coating. The study found that tungsten powder in the spraying process, particles are not completely melted, did not grow up, finally making the tungsten coating prepared by uniform thickness, the porosity is about 3%, showing good compactness, the coating effect is very ideal.
 
With high explosive explosion with superior technology, better uniformity and compactness of the coating loaded tungsten coating, although there is a concept of this technology, a lot of people, but there is no doubt that this coating technology has very broad prospects for development.
 

 

 

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