About Us
Contact Us

Mosten Alloy Co., Ltd.
Add: No.88 Jizhong Road, Shanghai,China    201609
Tel: +86 21 56656028
Fax: +86 21 56656030
Email: info@mostenalloy.com
News

Preparation process of high density tungsten alloy

Tungsten alloy is a kind of two-phase alloy with high density (≥ 16.5g/cm3), which is also called high density tungsten alloy. High density tungsten alloys are not only widely used in aviation, aerospace, weapons and other military fields, but also used more and more in the field of civil industry. The preparation process of high density tungsten alloy is as follows: 1. The tungsten content in the composition design of high density tungsten alloy is generally between 85 and 98 wt. In addition to W, Ni,Fe (Cu et al.) is the most important element in high density tungsten alloy. In the preparation of high density tungsten alloys, elements or compounds such as Mo,Ta,Re and La will be added. 2. The powder with high purity, small particle size and good uniformity will be used to prepare the alloy with excellent mechanical properties. In the field of powder making, nanometer powder is the research hotspot. There are two main types: 1) spray drying method is the first choice to prepare certain components of the original salt solution, salt solution including tungstate and metal chloride, the solution atomized to form small droplets. Due to the rapid evaporation of solvents and the rapid deposition of solutes in small droplets, uniform chemical composition of powders can be obtained. 2) the mechanical alloying method of mechanical alloying is to select a certain proportion of tungsten alloy initial powder and metal ball to put into ball mill. Under the action of different velocity of metal ball, the powder goes through cold welding and multiple deformation, and finally the microstructure is finer. Composite powder with more uniform composition. 3. The traditional forming process of tungsten alloy is die forming, the new technology is powder extrusion forming and powder injection molding. Because these two methods mix tungsten alloy powder with forming agent and then extrude into the forming machine, it is possible to produce parts with complex shape which has obvious advantages. Powder injection molding technology also has a wide range of applicability because of the addition of forming agent. 4. Because of the high requirement of the size of the original powder, the sintering time of the liquid phase sintering method is long, and it is easy to cause collapse and deformation. Two-step sintering process of solid-phase sintering and liquid-phase sintering was put forward by synthesizing their advantages and disadvantages. Because of the smaller deformation, the more uniform microstructure and the higher properties of the tungsten alloy, the two-step sintering is widely used. In addition, microwave sintering and spark plasma sintering, which have been developed in recent years, are also being popularized and used.