If you are not already using TiAlN coated end mills, you might want to make the switch. End mills and other milling cutters have to tolerate extreme forces and temperatures, which can shorten their tool life. If you are not using coated tools, then you might not be getting the most out of your cutters.
End Mill Fatigue
All high speed tools have to deal with fatigue. The strain caused by friction at high speeds is immense and can even damage your tools. This is particularly true with end mills made from steel alloys due to the fact that their hardness is directly related to the temperature at which they are tempered. If the heat from friction rises above the tempering point, the structure of the metal can realign into a pattern that is not as hard, limiting the effectiveness of its edges.
One way to avoid this is to use tools made from carbide, which get their cutting power from grains of carbide ceramic embedded in the tool stock instead of from heat tempering. Despite being more resistant to heat and lasting longer than steel tools, carbide tools will still fatigue over time. One of the best ways to extend the life of any milling cutter is to coat it in a material like TiAlN.
Titanium Aluminum Nitride
Known by its chemical shorthand TiAlN, titanium aluminum nitride is a special metastable tool coating. TiAlN coated end mills are capable of deflecting heat away from the body of the cutter and into the chips. One of the biggest benefits of TiAlN is the fact that it has a low coefficient of friction, which helps to limit wear resistance and less heat is generated. When heated, TiAlN produces a layer of aluminum oxide that helps to provide extra insulation during high heat applications.
Physical Vapor Deposition
Now when you think of a tool coating, you might worry that the thickness of the coating material could interfere with the sharpness of the tool’s edge. This would certainly be the case if we were talking about a coating that was crudely applied like paint, but tool coatings are deposited using physical vapor deposition. There are several techniques that are used but all involve placing the tools into a vacuum, vaporizing the coating material, and then having it resolidify on the tool surface. The major advantage of this is that a stable coating that is a fraction of a millimeter is achieved. Because the process takes place in a vacuum, the coating bonds directly to the body of the tool and offers incredible protection.
If you are interested in having tools that can run faster and last longer, then the TiAlN coated end mills available from Online Carbide are the perfect option. These tools are precision ground in the Us from high quality carbide and treated with titanium aluminum nitride TiAlN coating to offer a smooth surface finish that can withstand high temperatures. All of their tools are available at manufacturer direct prices when you visit their online store at www.onlinecarbide.com.