Tungsten Carbide: An Essential Part of Non Stick, Wear Resistant Coatings

Tungsten carbide is a popular hard metal used in industrial machineries, abrasives, and cutting tools. The said carbide is two times stiffer than steel, and is similar to corundum when it comes to hardness. However, the metal used in industrial machineries is actually composed of its hard particles mixed with metallic cobalt.
This hard metal is basically produced via a powder metallurgy process, wherein its powder is added with metallic cobalt using ball mills. In order to hold the powders together during the next process (called compaction or pressing), a binder material is added. The compaction or pressing process is then done under very high pressure using a mechanical press or an isostatic chamber.
The product of the said process will have a consistency similar to that of a blackboard chalk. In order to increase ‘green’ strength and maintain the compacted shape, a small amount of wax, usually paraffin, is then added. During this state, the compacted product can be made into its desired shape through turning, grinding, milling, and drilling. It is then subjected to sintering, in which the product is placed in a vacuum furnace at a high temperature. After this process, a dense, hard metal is then produced.
Tungsten carbide in wear resistant coatings
As previously mentioned, tungsten carbide has a wide variety of uses, especially in industrial machineries. This hard metal is a highly favored material used in coatings that are resistant to wear. This can be attributed to the hard metal’s unique properties, one of which is abrasion resistance, which is primarily due to the metal’s hardness. The metal’s hardness also allows it to have high impact strength and fatigue resistance, properties which are chiefly important in materials exposed to continuous cycles of stress fluctuation.
Additionally, this hard metal is also able to withstand very high temperatures compared to steel tools. This temperature resistance, which is due to its high melting and boiling points, allows faster machining for tools coated with this metal. This kind of carbide is also capable of maintaining its hardness values at high temperatures.
These properties are the reasons why this hard metal is the favored material for parts that must have a high degree of durability and parts that must be able to tolerate all forms of wear, such as sliding abrasion and erosion. These properties provide longevity in applications wherein other materials would not last or would easily fail.
Tungsten carbide in non stick coatings
Non-stick is a term that refers to surfaces coated with polytetrafluoroethylene, or PTFE. A famous brand of PTFE is Teflon. Special polymers like PTFE reduce the surface energy of the substrate surface, which effectively prevents a variety of substances, such as adhesives, rubber, and plastic, from sticking. Tungsten carbide is added to non stick coatings to achieve a certain degree of roughness, plus wear-resistance and durability. This enables non stick coatings to tolerate various degrees of mechanical abuses that would normally destroy regular coatings.
With this carbide’s numerous useful properties, such as its hardness, abrasion resistance, high impact strength, and high fatigue and temperature resistance, it is no wonder that this hard metal is preferred in various industrial and mechanical products.

Leave a Reply

Your email address will not be published. Required fields are marked *