Recently a military vehicle manufacturer came to Metalmite and asked them to make some idler shafts out of 6Al-4V Titanium instead of the 8620 steel alloy they were originally designed out of. The ATI Ti-6Al-4V Alloy (UNS 56400) is the most widely used titanium grade. It is a two phase α+β titanium alloy, with aluminum as the alpha stabilizer and vanadium as the beta stabilizer. This high-strength alloy can be used at cryogenic temperatures to about 800° F (427°C). ATI Ti-6Al-4V alloy is used in the annealed condition and in the solution treated and aged condition. Some applications include: compressor blades, discs, and rings for jet engines; airframe and space capsule components; pressure vessels; rocket engine cases; helicopter rotor hubs; fasteners; critical forgings requiring high strength-to-weight ratios. This alloy is produced by primary melting using vacuum arc (VAR), electron beam (EB), or plasma arc hearth melting (PAM). Remelting is achieved by one or two vacuum arc steps.
Metalmite found that the machining was not as difficult as they were originally told, it must be turned slower and not pushed like the steel alloys. The finish came out very clean and smooth. The parts were turned in the Mori Seiki lathe and inspected on the CMM afterwards to verify that they were right to spec. Another CNC Machining job well done by Metalmite.