Brindley Metals is one of the most approachable metal suppliers in the UK. We work to make it easy for clients to order the materials they need. One topic we would like to talk about here is palladium in titanium and its benefits. We supply a large amount of titanium grade 7 bar, plate and sheet, as well as forgings. So, we know how much palladium can improve the alloys.
Ever since its introduction in the 50s, titanium has become one of the most used metals in the world. Its use is considerable in the aerospace industry. At first though, it was a costly material to manufacture and use. Not surprisingly, many businesses chose other substances instead. However, with time it became easier to produce and less costly. The availability and use grew as a result.
If you compare to many other metals, pure titanium has excellent corrosion resistance. However, that does not mean it is immune to it.
Pure titanium is not corrosion proof
One of the most vital details is that this metal is not corrosion proof. It does perform well in the majority of corrosive settings. But, under specific conditions it is vulnerable.
Titanium gets its corrosion resistance from the oxide film. This forms in the presence of oxygen and moisture. However, in an anhydrous setting (one with minimal water) it is possible the oxide layer could not form. This means corrosion could occur.
Stress corrosion cracking
The presence of absolute methanol could lead to SCC. This is when it comes into contact with unalloyed titanium that has moisture content below 1.5%.
There are additional settings known to cause SCC in pure titanium too. These are ones that have gaseous bromine and fluorine, nitrogen tetroxide, and red fuming nitric acid.
Galvanic corrosion
When you couple two metals, one can function as the cathode and the other will act as the anode when they encounter an electrolyte. The metal that isn’t as noble shall turn into the anode here. As a result it will preferentially corrode. This is known as galvanic corrosion.
Titanium does not exactly behave this way though because it is high up the galvanic scale. It usually does not suffer with corrosion when you couple it with other metals. However, it can still happen in some cases. For example it can occur in reducing environments where the metal can’t passivate. It can also be a problem if the surface area of the titanium is much bigger than the other metal.
Palladium in titanium
Luckily, titanium can alloy well with other metals to boost the corrosion resistance. This is where palladium comes into play. Adding just a small amount of it can make the metal far more resistant. There is a huge amount of research to showcase this.
Normally, small levels of palladium can increase the resistance to reducing chemicals. This includes phosphoric, hydrochloric, and sulphuric acid.
In addition, adding Pd will increase the critical temperature at which crevice corrosion in sea water can happen. This makes the alloy a good option for products to use in marine settings.
First rate titanium grade 7 and more
We are specialists in our field. As a result, our people know a great deal about the metals we provide. So, if there is anything you don’t understand or want to learn, we are happy to help.
Titanium grade 7 is one of the most common alloys of the metal. Typically it contains just 0.2% Pd but this is enough to give the alloy much better corrosion resistance.
There are some other Ti/Pd alloys to look at too. For example, grade 17 has 0.05% Pd and grade 11 has 0.15% Pd.
So, if you want to know more about palladium in titanium or want to order these alloys, you can speak to us. We have titanium grade 7 in various bar, plate and sheet sizes. Plus, we can offer forgings too.