Decryption dart manufacturing phase I: tungsten steel
Why choose tungsten alloy for darts?
The first darts were made of wood. Copper darts came into widespread use only in the mid-20th century, as industry improved.
Wooden darts
Modern darts rules began to take shape, and various standards (darts size, distances, scoring methods, etc.) were established. The stout shape of copper darts is difficult to achieve high concentration, and the popularity of darts competitions has prompted manufacturers to develop new materials. The hardness, density, price of tungsten alloy...... It's the perfect dart-making material in every way. One of the main factors is density.
As can be seen from the above density table, the density of tungsten is close to that of gold and uranium, while other metals with a higher density than tungsten (iridium and osmium have not been determined as to which is higher) are extremely rare heavy metals and are difficult to be used in everyday use. Gold, the closest in density to tungsten, is more valuable and less hard, making it unsuitable for darts.
Pure tungsten
Pure tungsten comes in two forms. Formed tungsten metal block (tungsten content > 99.95%), very hard, but also very brittle, not easy to work. Tungsten powder (tungsten content > 99.5%) are used to make tungsten alloys.
Tungsten alloy
Tungsten alloy Tungsten and chromium, molybdenum, cobalt, nickel, iron and other alloys made of high hardness, heat resistance and wear resistance, used in the production of cutting tools, widely used in machining field. So tungsten cemented carbide is also known as the tooth of modern industry. The knives used to make the darts are tungsten alloy. The tungsten alloy used to make darts is tungsten-nickel alloy, which is divided into tungsten-nickel iron and tungsten-nickel copper.
The darts are made of tungsten steel
Ferro-tungsten is what we call dart steel. Tungsten steel for darts is slightly different from tool tungsten in that it contains more tungsten than tool tungsten but is slightly less rigid than tool tungsten. Cutting tool tungsten steel is a national standard and brand, and darts with tungsten steel because of the origin of different manufacturers do not determine the standard. This is why it is difficult to find tungsten data for darts on the Internet.
Dart tungsten steel is made of powder metallurgy process, the tungsten-nickel-iron powder after forming and sintering, processing into tungsten steel bar material. Tungsten steel has the characteristics of high hardness, high density and corrosion resistance.
The dart is made of tungsten steel, a bar slightly larger than the body of the dart.
Tungsten steel bar
For example, if the size of the darts to be manufactured is 7.1mm in diameter and 51mm in length, you can choose the bar material of 7.2mm in diameter and 52mm in length, and then make the darts into finished products through various machining techniques.
Tungsten content
The tungsten powder used in powder metallurgy mentioned above is actually tungsten carbide.
Tungsten powder
Tungsten carbide is usually represented by the English letter "WC". The tungsten content claimed by the darts manufacturer is the proportion of tungsten carbide powder. We often see these two letters on the names of traditional old darts. For example, 85% WC, 90% WC, the percentage refers to the amount of tungsten powder used in the material. Most darts manufacturers have now dropped the use of WC in their names, slowly diluting the concept. So a dart made of 90 percent tungsten is not 90 percent tungsten. Dart enthusiasts have previously used spectrometers to test different brands of darts. The darts made of 90% tungsten steel contain 85% to 88% tungsten, other elements including nickel, iron, carbon, and trace impurities.
Is the higher the tungsten content, the better the darts?
Not necessarily. The denser the tungsten, the more expensive it is, but that doesn't mean the darts are better. For a dart, the most important physical characteristics are weight and center of gravity. The main purpose of using high density tungsten is to achieve weight while making the darts smaller, so high density tungsten is used because it can be more dense. If you have two darts of the same length, diameter, weight, center of gravity, and shape, but with different tungsten content, then the two darts will be used in the same way.
What is the highest content of tungsten steel?
Currently, the highest content of darts on the market is 97% tungsten steel. The tungsten rods are 99.99 percent raw material, but they are not suitable for darts. In 2018, a domestic tungsten steel material manufacturer successfully developed tungsten steel with 98% tungsten content for darts, but it has not been put on the market. The guess is the difficulty of mass production and machining, do not know which brand will be the first to make 98% tungsten steel dart.
