Vacuum Compatible Materials

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Here are the most common grades of stainless steel you might come across in vacuum applications. Note that specifications between standards are used interchangeably but they are not exactly comparable.  

• Stainless steel EN 1.4301 often referred to as AISI 304 is widely used in vacuum applications due to it's corrosion resistance and low outgassing properties. Commonly used for making chambers, it is the cheapest suitable grade.  
• Stainless steel EN 1.4307 (and EN 1.4306) often referred to as AISI 304L is a low carbon grade of 1.4301. It's is more resistant to corrosion caused from welding. Vacuum flanges are generally made from 1.4307 or 1.4306
• Stainless steel EN 1.4401 often referred to as AISI 316 is more corrosion resistant than 1.4301. Readily available, but more expensive.
• Stainless steel EN 1.4404 often referred to as AISI 316L is a low carbon grade of 1.4401. It is more resistant to corrosion caused from welding. Used for vacuum flanges and pipes where very high corrosion resistance is required.
• Stainless steel EN 1.4435 often also referred to as AISI 316L has a higher nickel content than 1.4404.  It is hardly magnetic, even after welding. 
• Stainless steel EN 1.4429 often referred to as AISI 316LN has a higher nitrogen content than 1.4435. This means it is stronger and even less magnetic after welding. Availability in tubes and plate is low. 

Aluminium alloys are significantly less dense than stainless steel and have good strength-to-weight ratios. So vacuum chambers and components can be made from aluminium which are much lighter than they would be if they were made from stainless. 

Aluminium is also non-magnetic, so has a big advantage for applications involving charged particles. Aluminium has high thermal conductivity, which is useful for getting an even heat distribution during vacuum bake out or for heat management when conducting hot processes.  

Aluminium is highly corrosive resistant (due to the oxide layer) and has much less hydrogen permeation than stainless steel. 

For certain applications and configurations, aluminium can be a very cost effective solution.  Please get in touch for more information of aluminium vacuum hardware. 

Mu-metal is a nickel-iron alloy with very high magnetic permeability that has a low coercivity that saturates at low magnetic fields, providing excellent magnetic shielding properties.

Mu-metal is a more costly material than stainless steel or aluminium, and it requires a more complex manufacturing process. This means Mu-metal chambers are significantly more expensive so are only used where static and low frequency magnetic fields would be detrimental and need to be shielded from.

Flanges on Mu-metal chambers are typically made from 316LN ESR which has a low magnetic permeability. 

We also supply shields or liners for use inside or outside the chamber to reduce the effects of magnetic fields. 

Nickel alloys have a high tolerance to heat and chemical attack.

Certain grades of Inconel®  have high corrosion and oxidisation resistance, and maintain their tensile strength at high operating temperatures.  It is machinable and certain grades can be easily welded.

Monel® is a nickel-copper alloy which has  enhanced corrosion resistance and makes it particularly strong against sea water as well as hydrochloric and sulfuric acids. 

Get in touch with Concept Vacuum to find your perfect nickel alloy.  

Advanced technical ceramics are a class of materials that offer a unique combination of properties, making them ideal for a wide range of high-performance vacuum applications. Concept Vacuum design and supply components machined from:

• High purity alumina (purity > 99.7%)
• Boron Nitride
• Aluminium Nitride
• Macor and Mykroy

 Some of the most important features of advanced technical ceramics include:

• High strength: Advanced technical ceramics can be very strong, making them ideal for applications where high loads need to be supported.
• High temperature resistance: Advanced technical ceramics can withstand high temperatures, making them ideal for applications where heat is a concern.
• Corrosion resistance: Advanced technical ceramics are resistant to corrosion, making them ideal for applications where corrosion is a concern.
• Chemical inertness: Advanced technical ceramics are chemically inert, making them ideal for applications where chemical exposure is a concern.
• Electrical insulation: Advanced technical ceramics are excellent electrical insulators, making them ideal for applications where electrical insulation is required.
• Hardness: Advanced technical ceramics can be very hard, making them ideal for applications where wear and abrasion resistance are required.

We are experts on these advanced technical ceramics, and can help you find the perfect material for your application. Each material varies in mechanical, electrical and thermal properties and there are a wide range of different grades and compositions. Get in touch with Concept Vacuum to find your perfect technical ceramic.