Laser in Vacuum Welding Machines

Laser in vacuum (LiV) welding is a relatively new technique that has the advantage of two to three times the depth of weld compared to conventional laser welding with shielding gas. It also has the benefits of reduced oxidation and extremely high welding quality.

Increased Beam Penetration and Quality

Conventional laser welding at atmospheric pressure leads to a build-up of hot metal vapour above the keyhole. This vapour plume scatters and refocuses the laser beam and drags chunks of molten metal from the melt pool, forming spatters.

Laser welding in a vacuum eliminates the hot vapour plume, as it can now expand away from the keyhole vicinity much more quickly. This process leads to a higher laser coupling-in efficiency and minimises spatter.

The vacuum environment also reduces the temperature at which the metal boils – allowing for double to triple penetration depth.

The approximate 1000K drop in boiling point (depending on the material) allows for a significantly larger fraction of the beam’s energy to be expended in vaporising the material.

The vacuum surrounding the keyhole and melt pool allows for more effective degassing, and of course, does not contain any air to oxidise the workpiece.

This results in drastically reduced porosity and a completely oxidation-free weld bead.

Benefits of Laser Welding in Vacuum
  • An increase of over double the welding depth than in air
  • Parallel-sided seams with reduced nailhead
  • Increase process stability due to significantly reduced and stable plasma plume
  • Reduction of workpiece contamination by spattering and vaporisation
  • Higher-quality, pore-free weld seams
  • Low operating costs due to efficient solid-state laser
  • Welding process without inert gas
  • No requirement for x-ray shielding
  • Suitable for magnetic materials
Applications

The above features make vacuum laser welding a robust procedure to achieve high penetration welds.

Laser welding in a vacuum can also prove more flexible than electron beam welding in some applications due to the absence of X-rays and the avoidance of magnetism issues.

The application determines the choice between electron beam welding and laser in vacuum welding. For a detailed breakdown of the suitability of electron beam or laser for your application, why not contact us?

Gallery

A gallery of weld cross-sections, as well as CVE’s development system.

S355 stainless steel LiV welds >20 mm depth using a 6kW laser.

CVE

CVE’s laser welding in vacuum development system.

CVE

1-4kW LiV welds at 1m/min into S304 stainless steel.

CVE

Laser welding head.

CVE
Laser Welding Machines

Conventional laser beam welding is a process that typically occurs at atmospheric pressure, using a shielding gas.

Shield gasses are consumable and are often necessary to protect the weld area from oxygen and water vapour.

As part of the LBW equipment, we incorporate suitable extraction systems; and compared with electron beam welding, there are no x-rays produced, so it does not require an expensive vacuum chamber.

This also means that productivity can be high, especially where one source delivers multiple beams.

Our machines perform the weld in a protective atmosphere and include a complete work handling package. We can also set up the machine to make the process fully automated.

We offer a variety of laser, optics, and welding heads.

CVE

Conventional laser beam welding is a process that typically occurs at atmospheric pressure, using a shielding gas.

Shield gasses are consumable and are often necessary to protect the weld area from oxygen and water vapour.

As part of the LBW equipment, we incorporate suitable extraction systems; and compared with electron beam welding, there are no x-rays produced, so it does not require an expensive vacuum chamber.

This also means that productivity can be high, especially where one source delivers multiple beams.

Our machines perform the weld in a protective atmosphere and include a complete work handling package. We can also set up the machine to make the process fully automated.

We offer a variety of laser, optics, and welding heads.

CVE

Ebflow light combines the benefits of laser welding in a vacuum, including deep penetration welding and exceptional quality, with CVE’s patented local vacuum systems.

This enables large fabrications to be welded on-site, with a thickness of up to 60mm achievable in a single pass.

In addition, weld speeds of up to 30 times faster than those achieved by arc welding processes are achievable.

Benefits of Local Vacuum
  • Improved weld penetration depth for a given power
  • Better weld quality, low porosity, and spatter
  • Reduced consumption of expensive process gas
  • Self-contained laser safety – no cell required
  • Less demanding vacuum conditions than electron beam
  • Immune to magnetism issues

 

Specification

Beam Power

6kW
Depth of Weld Up to 60mm
Vacuum Range 10-1 – 10-2 mbar range
CVE
Benefits of Local Vacuum
  • Improved weld penetration depth for a given power
  • Better weld quality, low porosity, and spatter
  • Reduced consumption of expensive process gas
  • Self-contained laser safety – no cell required
  • Less demanding vacuum conditions than electron beam
  • Immune to magnetism issues

 

Specification

Beam Power

6kW
Depth of Weld Up to 60mm
Vacuum Range 10-1 – 10-2 mbar range
CVE
Ebflow Light Explainer Video

An Introduction to Laser Welding

Laser welding (LW) is a welding process that uses a high-power density laser beam to join two materials together, creating a deep, narrow weld.

 

How Does Laser Welding Work?

LW is a technique that is known for its versatility and high productivity, especially for thin section materials, and for welding at high speeds.

Compared to other welding techniques, such as MIG and TIG, LW has relatively low heat input overall, resulting in low distortion, excellent mechanical properties, and minimal post-weld machining.

CVE has completed a thorough programme of development work over the past few years, developing systems for welding in a protective atmosphere, in a vacuum chamber and with a local vacuum.

CVE
Vacuum

Conventional laser takes place at atmospheric pressure, with additional shielding gas. However, you can laser weld in a vacuum, which significantly increases the depth of the weld.

 

Component size

LW with a shielding gas can accommodate any component size, as there is no vacuum chamber. Furthermore, you can use fibre optic delivery systems. This allows the welding head to be remote from the power source.

 

Automated Process

Machines can be highly automated with high production rates, in addition to there being no waiting time for chamber evacuation. Beam splitting and beam sharing are also possible.

CVE
Weld Characteristics

The process presents the following characteristics:

  • Deep, narrow weld
  • Excellent mechanical properties
  • High speed, high productivity
  • Low distortion
  • Minimal post-weld machining
  • Suitable for thin section materials

 

CVE's Laser Welding Machines

Please find our full range of machine models below.

CVE has completed a thorough programme of development work over the past few years surrounding laser, developing systems for welding in a protective atmosphere, in a vacuum chamber and with a local vacuum.

If you are not sure which system is right for your application, please get in touch! Our machines are built-to-order and manufactured at our Cambridge Headquarters. With 60-years of process know-how in providing turn-key solutions, we find the right solution for your application.

CVE operates a Quality Management System that complies with the requirements of BS EN ISO 9001:2015.

GET IN TOUCH

If you’d like to know more about our products or would like to speak to one of our team, then please get in touch. We look forward to hearing from you!