I was asked by a company to produce some parts in a material that I was unaccustomed with, the material was called Ferralium. The part that I had to machine had very high tolerances involved in its production, a very small batch was needed and Stotfold Engineers was singled out to uphold and perform the task. Ferralium was an unusual material in as much as it does not like to be machined lightly (I.E. small cuts). Boron nitride cutters were the order of the day for the cutting tips. Initial roughing cuts were about .050 deep and the finish cuts were .005 deep. There were hols that had to be drilled to take a thread with zero truncation. The Ferralium drilled remarkably well as the low speed high feed rate was maintained with a high speed drill bit. Tapping threads in this material was another matter as normal high speed taps no matter how good they will not tap Ferralium. Special Titanium taps were procured to complete the finished article.
As you can see in the picture there is an Ferralium mounting plate that had a bend in it. When bending Ferralium, larger that normal bending radii have to be employed as the material will crack.
In the following pictures it shows a roller being machined on one of our heavy duty lathes it is used for forming wood pellets, there are a series of three rolers that work in combination together to form the pellets. The rollers are made from a bearing material at a hardness of 62 rockwell, this needed to be machined using Boron Nitride cutting tips “one of the hardest man made materials”. After lots of many small cuts we were able to complete the job. as can be seen in the final picture.
