How To Machine Titanium

This article is the first in a multi-part series taking an in-depth look at the handling and working with titanium. The series is split into parts Machining, Forming and Welding with the first part Machining spanning a number of articles. This first article provides guidance and an introduction to the metal and how it should be considered when it comes to effective machining.

Titanium may be machined effectively as long as processes and techniques make considerations for the properties of the metal. Whilst it is not as overly complex activity it is a very important step as the metal differs greatly from other metals and within itself in the form of its alloys and so an understanding of titanium machining is necessary.

Differing titanium grades and from alloy to the commercial pure grades of titanium have differing machining characteristics similar to the difference that exist in the different grades of steel. Similar to stainless steel titanium has a thermal conductivity which is low and as such results in heat being dissipated from machine pieces and hence requiring the application of coolants during machining.

Key factors in ensuring quality machining of titanium and titanium alloys are:

  • Always keep tool and bits sharp to reduce galling and heat focus
  • Do not scrimp on coolants and use generously to ensure high heat transfer
  • Make use of lower speeds of cutting
  • Remove turnings as soon as possible
  • Remove turnings as soon as possible
  • Rigid jigs are useful in countering flex in the working pieces

It is common knowledge that the machining of commercially pure titanium is significantly easier to machine than any of the titanium alloys. In fact there are commonalities with other metals that are useful guide. Commercially Pure titanium is often likened to 18-8 stainless steel for its machine-ability. The titanium alloys on the other are much harder to machine.

The follow up articles to this part of the series will cover the following areas and individual machining techniques:

  • Turning
  • Milling
  • Drilling
  • Tapping
  • Grinding
  • Sawing
  • Water Jet
  • Electric Discharge Machining
  • Chem Milling