Home >> Technical FAQs >> milling of aircraft engine components with pcd inserts

milling of aircraft engine components with pcd inserts

Many aircraft engine components are now made with titanium. Titanium alloys, such as Ti6Al4V, are frequently used for engine parts that fit into the compressors installed in front of the jet engine. This lightweight material is strong, has the capacity to withstand rapid changes in temperature, and reduces the total weight of the aircraft engine. However, machining titanium poses special challenges because of the risk of high temperature build-up. Due to the titanium's low thermal conductivity, machining it at a high speed can lead to a fire outbreak.

Titanium also reacts rapidly with tooling materials and causes chips to weld to the cutting edge. It is also brittle and produces stringy, tough and abrasive metal chips during machining. Hence, a super-hard cutting insert like the polycrystalline diamond pcd insert should be used. This type of cutting tool can withstand temperatures as high as 700 degrees. Here is a short description of some of the machining process involved in producing aircraft engine parts and the kind of pcd inserts recommended for them.

pcd inserts for Milling Titanium-based Components
While machining titanium-based alloys, inserts with well balanced cutting edges are required. Polycrystalline diamond inserts offer well balanced cutting edges and longer tool life than other ordinary carbide inserts. For rough milling of titanium alloy components, the parallelogram shaped 85-degree APCT may be used with suitable milling cutters. This insert is a low resistance cutting insert with tough cutting edges. It also has a chip breaker that enhances the removal of the titanium chips and prevents them from getting welded to the cutting edge. The counter sunk hole also helps to increase the rigidity of the insert and enhance its cutting strength.

Other inserts that may be used for rough milling include the APET and RPGG inserts. Round inserts like the RPGG insert geometry help to minimize notch wear. For best results, the depth of cut should not be more than 15 percent of the round insert's diameter. After rough milling, machining of titanium-based aircraft components may be finished with the TPKT insert. With three cutting edges, wiper technology, and a positive geometry, this indexable insert provides an accurate surface finish. It may also be used for medium machining of intricate parts that can only be reached with small end milling cutters.

Polycrystalline Diamond pcd Inserts for Turning Titanium Alloy Components
For excellent cutting performance, turning of the internal, external parts of titanium alloy components should be done with the CNMG insert. This indexable turning insert has double chip breakers and a negative geometry for aggressive metal removal. In place of this insert, other geometries such as DNMG and TNMG may also be used. With a suitable milling cutter, the cutting speed may be set to 260 m/min or a lower speed. The cutting speed has a significant influence on the lifetime of the cutting insert. Similarly, the feed rate should not be more than 0.2 mm/rev while the cutting depth should be at least 0.25 mm, to avoid the risk of chipping.

Conclusion
The challenges posed by titanium-based alloy components can be overcome by using the appropriate type of cutting inserts. Polycrystalline diamond pcd inserts can absorb a great amount of heat, provide weld-resistance, and deliver a high quality surface finish.

We export PCD inserts to world wide countries, such as USA united states, Germany, UK united kingdom, Italy, France, Turkey, Russia, Saudi Arabia, United Arab Emirates, Ukraine, Israel, Canada, South Africa, South Korea, Japan, Australia, New Zealand, Finland, Sweden, Norway, Danmark, Switzerland, Poland, Czech,Ireland, Holand, Belgium, Greece, Croatia, Spain, Portugal, Egypt, India, Philippines, Cambodia, Thailand, Malaysia, Singapore, Indonesia, Mexico, Brazil, Colombia, Chile, Argentina etc.