Brindley Metals is here to provide the finest metal products UK clients can ask for. This is not our sole area of expertise though. Something else we strive to do is assist with processing. One of the things we can arrange is titanium alloy machining. This can yield some wonderful results to suit a variety of needs.
Titanium is a costly and difficult material to machine. It is true that it is not as popular amongst machine shops if you compare to aluminium or steel. This is primarily due to the high manufacturing and material costs. Machinability rates range between 15% and 45%, meaning some machinists can struggle.
What is titanium?
If you haven’t used it before, titanium is a chemical element possessing the symbol Ti. You can find it in commercially pure forms as well as a range of alloys. The latter are generally 88% Ti along with alloying elements. Said elements are mostly aluminium (Al) and vanadium (V).
What makes this a useful and distinct metal are multiple attributes you can’t find together in other substances. Titanium has a brilliant strength-to-weight ratio. On one hand, it is nearly as light as aluminium. On the other, it possesses a strength surpassing that of most steel alloys. Even better, the corrosion resistance is spectacular. Thanks to this combination of factors, it is popular for medical implants and aerospace components.
Now that we know about the ins and outs of titanium, we will talk more about its machinability. For one thing, this material has extremely low heat conductivity. What this does is cause heat from the cut to move primarily to the cutting tool. It does not flow to the workpiece and the chips.
Something else titanium has is extreme flexibility. Because of this, it bends with ease by the cutting forces. You must factor this in to get accurate results.
Some of the more popular alloys of titanium possess high hardness as well. For instance, there is the popular Ti-6AI-4V alloy. It has 32 HRC. Other alloys can also reach as high as 40 HRC. You need to think about this when you come to titanium alloy machining.
Pure titanium alloys are certainly the easiest to machine. They are not completely “pure” because they have 99.5%-99.8% Ti. There is also a small amount of carbon (C) and iron (Fe). We classify them according to the titanium content as grade 1 through to grade 4. Grade 2 is the most popular one.
The hardness and machinability of pure titanium
We will go into the details of the hardness and machinability of each pure titanium grade.
- Starting with Ti-99.5 (grade 1), it has a hardness of 100 HRC and a machinability of 46%.
- Ti-99.6 (grade 2) has a hardness of 90 HRC and a machinability of 40%.
- Ti-99.7 (grade 3) possesses a hardness of 80 HRC and a machinability of 35%.
- Finally, Ti-99.8 (grade 4) comes with a hardness of 70 HRC and a machinability of 28%.
The machinability of titanium alloys
To finish off, we shall look at a range of alloys.
- With Ti-10.2.3, it has a hardness of 35 HRC and a machinability of 18%.
- Ti-13V-11Cr-3AI possesses a hardness of 40 HRC and 15% machinability.
- Ti-15-333 has a hardness of 32 HRC and a machinability of 20%.
- Ti-15Mo (Alpha+Beta) comes with a hardness of 38 HRC and a machinability of 16%.
- Ti-15Mo (Beta) has a hardness of 24 HRC and a machinability of 28%.
- Ti-3AI-2.5V possesses a hardness of 24 HRC and a machinability of 28%.
- Ti-425 comes with a hardness of 36 HRC and a machinability of 17%.
- Ti-5AI-2Sn-2Zr-4Cr-4Mo holds a hardness of 38 HRC and a machinability of 16%.
- Ti-6-7 has a hardness of 32 HRC and a machinability of 20%.
It is important to keep all of these properties in mind so you know what to expect with pure titanium grades and alloys. You will need to adapt the titanium alloy machining to suit the hardness.
Plus, you need to look at other factors that could make the metals harder. For example, most alloys will undergo heat treatment to a hardness of 30-40 HRC. Such a combination provides them with outstanding mechanical characteristics. At the same time, they become far tougher to machine if you compare to pure titanium.
Ask us for help with titanium alloy machining
With Brindley Metals, you are able to access a diverse collection of services and metal products. You might be looking for some brass and yellow metals, or some specialist ones like thin foil. Alternatively, your situation could require some form of processing. However, whatever it is you need, we will do all we can to provide it or connect you with someone who can.
So, please let us know if there is anything we can do for you, from metal supply to titanium alloy machining.