Using good carbide is like using thin kerf saw blades.
The differences are not dramatic but they are important.
Good carbide will reduce breakage, give better quality cuts, and make better quality tools overall.
Choosing The Correct Grade Can Make A Huge Difference In Performance.
In our fourteen most common grades the hardness (Rockwell A) ranges from 84.
5 to 92.
3, density (g/cc) runs from 13.
5 to 15.
05 and Transverse Rupture Strength (psi.
) goes from 270,000 to 400,000 - the differences in wear and impact resistance from the top to the bottom are huge.
Tungsten carbide is a powdered metal material that is shaped into parts using 4 different techniques.
The way that the Tungsten Carbide Powder is shaped can have an impact on the quality of the finished piece.
1.
Molding - The first way is molding the carbide into whatever shape you desire.
Molds are built and the tungsten carbide is pressed to shape.
This process has the lowest carbide parts cost, but one has to figure at least $3,000 - $5,000 in expenses for the mold.
Molding the carbide produces carbide pieces with good shape and edge definition.
2.
Green state machining - The second way is 'green state' machining.
Manufacturing Tungsten carbide is a multi step process.
At some point during the process you end up with a shape that is softer than sidewalk chalk and that can be shaped easily.
After this 'green state' shaping the part is 'finish sintered' and shrinks about 40% with consequent dimension and edge changes.
If edge definition is critical, the carbide must be grinded after the final sintering.
This process is lengthy, and usually results in high labor costs.
3.
Grinding - The third way is to take a finished shape and grind the desired configuration.
This process requires Diamond Grinding, but can be fast, and produces excellent shape and edge definition.
4.
Brazing carbide to carbide - The fourth way is to take two or more parts and join them typically by brazing.
This process is not very common, as its purpose is to use the least expensive carbide as is possible to find and braze it to steel or a similar metal.
There is a fine line in balancing the carbide so that it is both as tough and wear resistant as possible.
· More cobalt means it is harder to break but does not wear as well.
· Smaller grains mean more wear resistance.
· More wear resistance means less toughness, which is the ability to withstand fracture.
· Toughness increases with an increase in cobalt and with an increase in grain size.
· Hardness increases with a decrease in cobalt content and a decrease in grain size.
· Transverse rupture strength (T.
R.
S.
) increases with an increase in cobalt content.
Finding just the right balance to keep the carbide tough while maintaining a good wear resistance can prove to be difficult.
Carbide Processors have been in the carbide and tooling industry for over 25 years, and have extensive knowledge of the right type of carbide and the perfect balance of toughness and wear resistance for any carbide application.
They are a great source if you are looking for quality carbide for saw tips or for custom tools