Technical Articles About Titanium
Titanium Machining With High Efficiency
Titanium alloy is a high strength metal with heavy viscosity, it's easy to generate and gather heat on cutting section during cutting. What's worse, there is a risk to cause fire when milling for a long time because of titanium's poor thermal conductivity. Since high speed cutting is not good for machining titanium alloy materials, it's a difficult problem for many companies engaged in producing top grade parts to make work efficient to process the titanium alloy. There are some methods to do the work better to a certain extent as below:
1. Get a new high speed steel instead of traditional hard alloy. In most cases, hard alloys are the first choice for metal machining because of its good wearing resistance and red hardness and resonable machining costs. But people always forget their frangibility which is the the most important matter for machining titanium alloys. The abrasion of the knife edge is not the reason to make cutter disabled but the blade's broken. Furthermore, the high temperature caused by machining the titanium alloy material stop giving play advantages of high speed chipping. So large quantities of cooling fluid is required during high speed chipping. This cold and hot change causes an intensive impact between the cutter and the aparts, which can break the edge of blades of the fragile hard alloys. Then the expensive cobalt high speed steel and powder metallurgy high speed steel are the first choices for gang milling of titanium alloys. And this is the necessary condition to use high speed steel instead of hard alloys in traditional machining.
2. Hard alloy cutter can reach a marvelous high speed to adopt the small radial direction cutting method to machine the titanium alloy parts with traditional machining. The small radial direction cutting method means to cut from the radial direction cutting depth which is much smaller than the cutter radius when machining the parts. This method can reduce the cutting time of each blade and extend the blades' no-cutting time, which means increasing the cooling time and getting a well control for cutting temperature, so the cutting speed can be raised substantially. Usually it can raise the cutting speed by 50% when the cutting depth is smaller than 25% of the diameter and by 100% when the depth is less than 10% of the diameter.
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