The most common materials you will see in structural metal fabrication projects are grades of steel and aluminium. People using the latter will likely choose either grade 7075 or 6061. There are some similarities between the two but it is vital to know about the differences. This way you can ensure you choose the right one when you need aluminium bar and plate or other forms of the metal.
The series and chemical composition
As you can see from the names of the grades they don’t come from the same series. Therefore you can tell right away that they will have a different chemical composition. If you look at the data sheets for each material you can see all these differences. Most notable is the fact that 7075 has way more zinc and slightly more magnesium in its alloy. It also contains copper, which 6065 does not. What it does have though is more silicon.
To do a proper comparison between the grades you need to consider what their properties will be if they both receive the same type of heat treatment. The most impressive differences are when both alloys are T6. Here 7075 has an amazingly better tensile strength, close to double what 6061 can achieve. It also has a higher shear strength and hardness.
While the hardness and strength can be a major benefit for 7075, it does mean it is harder to form and machine. This gives 6061 a little bit of an advantage. It also edges ahead slightly because it is weldable. Unfortunately 7075 is likely to crack after welding, so most people say it is not weldable. You can join both grades with brazing and soldering though.
There is a great deal of overlapping here but there are some preferences with the grades. For example grade 7075 is the best option for structural parts for aerospace applications and things like bikes because of its higher strength. On the other hand, the formability of 6061 makes it a better option when the structural shapes need contouring. This includes items like tanks. Most industrial tooling will be 7075.
Do you want to order grade 7075 aluminium bar and plate?
Brindley Metals works hard to be one of the most approachable metal stockists in the UK. We support our clients by finding reliable sources of these substances around the world. In addition, we can arrange various services like wire erosion and processing. This means clients can come to us for all kinds of needs.
So, if you want aluminium bar and plate, whether it is grade 7075 or one of the other ones we carry, please contact us.