What Is Hybrid Laser Arc Welding?

Table of Contents >

1. Basics of Laser Welding and Arc Welding
    1.1 Why Laser and Arc Welding Work So Well Together?
2. What is Hybrid Laser Arc Welding?
    2.1 How Does Hybrid Laser Arc Welding Work?
    2.2 Key Parameters of Hybrid Laser Arc Welding
    2.3 Advantages of Hybrid Laser Welding
    2.4 Industrial Applications of Hybrid Laser Arc Welding
3. Hybrid Laser Arc Welding Vs Arc Welding vs Laser Welding
4. Final Thoughts
5. 🧐What Is Hybrid Laser Welding? FAQ

Traditional welding has undergone significant changes since its discovery and inception. However, many industries today still rely on conventional arc welding methods.

Laser welding is one of the latest and certainly advanced types of welding. Welders favor it when precision, speed, and quality are crucial. Nonetheless, both arc and laser beam welding have process-related drawbacks.

To address these issues, scientists developed a solution. They combined the basics of laser welding and arc welding into a process called Hybrid Laser Arc Welding (HLAW). In this article, we will outline the fundamentals of hybrid laser welding, its advantages, and its various applications.

Hybrid Laser Arc Welding Process
Source: https://www.youtube.com/shorts/odQD2WdioEY

Basics of Laser Welding and Arc Welding

To help you understand the fundamentals of hybrid laser welding, we will first discuss the basics of both parts of the equation: laser welding and arc welding.

Laser beam welding (LBW) uses a powerful laser beam to melt and fuse the pieces. The laser beam forms in a laser source, which can be a gas, a solid, or a diode. However, the laser itself is not powerful enough to melt and fuse the pieces.

The beam travels through an optical fiber, and a series of lenses and mirrors transfers and focuses it into a tiny spot. Focusing a powerful beam down to a small spot creates very high energy density, which is sufficient to melt, cut, or weld pieces.

How Does Laser Welding Work
Source: https://www.stylecnc.com/blog/laser-welding-vs-plasma-arc-welding.html

Arc welding, on the other hand, uses the heat of an arc to melt and fuse the pieces. The arc forms between the electrode and the base metal once the electrical circuit closes. The electrode is connected to one part of the terminal, and the base metal is connected to the other part of the terminal. So, once you close a circuit, an arc forms.

The exceptionally high heat of an arc melts the base metal and filler metal. As everything solidifies, it creates a bond known as a weld.

What is Arc Welding?
Source: https://www.twi-global.com/technical-knowledge/faqs/what-is-arc-welding

Why Laser and Arc Welding Work So Well Together?

Arc welding and its methods, such as MIG or TIG welding, are straightforward and highly versatile. They can weld a wide variety of metal types and thicknesses. However, these methods have some flaws.

Firstly, manual arc welding methods are slow. Manually performing welding often carries the risk of operator error and requires a significant amount of time. Lack of precision, heat control, and speed can lead to inefficiency and defects in industrial applications.

Manual MIG Welding Process
Photo by @Morteza Mohammadi (IG)

Laser welding addressed many of these issues. This method is fast, efficient, and very precise. Additionally, it provides exceptional heat control, which is ideal for working with thin sheet metal.

However, laser welding is not perfect either. Its efficiency drops on reflective surfaces that bounce the laser beam off. Additionally, laser welding works best with ideal part fit-up and proper alignments. Welding thicker parts with a wide joint requires high-powered lasers and specific joint preparation.

To maximize the benefits of both arc welding and laser, scientists have combined their advantages and overcome their limitations in a process known as Hybrid Laser Arc Welding (HLAW). Let's further explain what it is and how it works.

Hybrid Laser Arc Welding Process
Source: https://blog.atfco.com/how-hybrid-laser-welding-is-making-cranes-stronger

What is Hybrid Laser Arc Welding?

Hybrid laser arc welding (HLAW) combines fundamentals of laser welding and traditional arc welding methods, such as MIG/MAG or TIG welding. In brief, this process utilizes arc and laser welding in a shared weld pool.

The concept of combining arc welding and laser welding originated in the 1970s. The process was defined as "arc-augmented laser welding", and it highlighted the clear advantages of integrating an electric arc and a laser beam for welding.

However, it took years of improvements to put theory into practice. As a result, the first industrial hybrid laser arc welding system was introduced in 2000. Later, this system was installed in several industries, and today, numerous hybrid laser arc welding systems are commercially available.

In theory, you can combine any laser (CO2, Nd: YAG, diode, Yb fibre, etc.) and arc welding method (MIG/MAG, TIG, FCAW, PAW, or SAW). However, due to various operational challenges, CO2 or Nd: YAG lasers are most commonly combined with Gas Metal Arc Welding (GMAW or MIG) and TIG.

Hybrid Laser Arc Welding Process
Source: https://mshoham.co.il/hybrid-laser-welding-combining-different-welding-techniques/

How Does Hybrid Laser Arc Welding Work?

The working principle of Hybrid Laser Arc Welding (HLAW) is unique. The process works by simultaneously directing a laser beam and an electric arc onto the same molten weld pool.

Working Principle of Hybrid Laser MIG Welding
Source: https://www.youtube.com/watch?v=NYCPDLPKoJQ

Here is a step-by-step explanation of HLAW:

The laser initiates a keyhole. A tightly focused, narrow laser beam carries high energy density. This power evaporates surfaces and creates a cavity known as a keyhole. This keyhole allows the laser energy to penetrate deeply into the material.
Arc supports a laser beam. Simultaneously, MIG/MAG or another arc is directed close to the laser spot. This arc preheats, adds additional material around the keyhole, deposits filler wire, and stabilizes the molten pool.
Shielding gas. External shielding gas protects the molten weld pool from atmospheric contamination. Additionally, shielding gas affects the depth of penetration and arc stability. Hybrid welding typically uses high-purity inert gases such as Argon or Helium, but small amounts (<5%) of CO2 or O2 can aid in pool fluidity, speed, and reduce spatter.

Hybrid welding uses high-purity argon or helium for clean welds.
Source: https://www.youtube.com/watch?v=toquox5ipiM

Energy synergy. The arc and the laser beam combine energy to form a larger, more stable weld pool than either process alone. A laser beam improves precision and narrows the HAZ, while an arc lowers the laser's reflection losses and stabilizes the arc.
Weld pool dynamics. Both heat sources overlap slightly during welding, resulting in a balanced weld geometry (in terms of depth and width). A laser beam creates a very deep, but narrow keyhole. An arc with additional filler metal adds width and reinforcement.
Solidification. Overall heat input is lower than that of arc welding (but higher than laser welding alone), resulting in improved solidification. Combined and controlled heat limits the risk of distortion or cracking buildup. There is—lower speed yields deeper penetration and wider welds.

Hybrid Laser MIG Welding
Source: https://www.youtube.com/shorts/DXOwZG7xuzY

Key Parameters of Hybrid Laser Arc Welding

Merging two heat sources into a single welding process results in an increased number of parameters. However, it also presents a big challenge, as the values of the parameters that are ideal for each process separately are likely not optimal for HLAW combined.

Laser Hybrid Welding Process
Source: https://www.youtube.com/watch?v=8u8wvwQhWv8

Key parameters of hybrid laser arc welding include:

Laser wavelength: The wavelength of laser light depends on the laser type. CO2 or Nd: YAG lasers, as the most common ones, produce a different spectrum that affects the distance between the arc and the laser source.

Types and Wavelengths of Welding Lasers
Source: https://www.xometry.com/resources/sheet/laser-wavelength/

Laser power: The power of the laser, expressed in watts, directly affects its penetration. The higher the power, the greater the penetration of the laser. But, since the arc in hybrid welding also heats the metal, lasers are more efficient, especially on reflective surfaces.
Process layout: Depending on the process, type of metal, and electric arc, there are two layouts. In the first layout, the laser is the primary source of heat, whereas in the second layout, the arc initially heats the metal.
Distance between the laser and the arc: The distance between the two heat sources affects the hybridization effects. If the distance is too short, the arc can absorb part of the laser beam. If the distance is too great, the benefits of both sources are neglected.
Shielding gas: it affects penetration and pool stability. In hybrid MIG welding, it can also affect the transfer mode (pulsed/spray arc is recommended).
Welding speed: HLAW is a fast process; however, the speed affects both penetration and width. The faster the process goes, the less heat buildup there is—lower speed yields deeper penetration and wider welds.
Angle of electrode: In HLAW, the laser beam directly hits the joint, while the angle of the electrode is typically set around 45–65 degrees.

Laser Hybrid Welding Tip: Position the electrode at 45°–65°
Source: https://www.laserline.com/en-int/laser-hybrid-welding/#c823

Advantages of Hybrid Laser Welding

As mentioned, hybrid laser arc welding combines the best aspects of both laser welding and arc welding. The most notable advantages of HLAW are:

Higher welding speed: Laser welding is a swift process, and combining it with arc welding greatly increases its speed. Due to the nature of the laser, the process is much faster than arc welding alone. Adding arc heat can increase the speed of HLAW by 30% compared to laser beam welding alone.

Comparison of HLAW and Standard Welding Process in Welding Efficiency
Source: https://www.youtube.com/watch?v=8u8wvwQhWv8

Deep penetration combined with better gap tolerance: The Focused heat of the laser beam can yield deep penetration, but it has issues when bridging wide gaps on thick metals. That's where filler metal and gap bridging of arc welding present advantages. Added filler metal fills larger joints, while maintaining deep penetration of laser welding.
Ability to weld various thicknesses: HLAW is a versatile process that enables welders to join both thin sheets and thick pieces of material. A combination of Nd: YAG laser and MIG/MAG welding is suitable for thin sheets, while a CO2 laser and MIG welding with thicker wire work well for thick pieces.
Less heat input: Laser welding offers controllable heat input, which is sometimes lacking in arc welding. The narrow HAZ and excellent heat control reduce the risk of distortion, warping, and burn-through.

Comparison of HLAW and Standard Welding Process in Heat Input
Source: https://www.youtube.com/watch?v=8u8wvwQhWv8

Reduced operational costs: Increasing welding speed and wire efficiency, while maintaining good penetration and improving metallurgical characteristics, reduces costs. Adding arc heat reduces the reflectivity issues of the laser, reducing power consumption and overall operational costs of the process.
High-quality welds: Combining a laser beam and arc stabilizes the weld pool. With added heat control, HLAW can produce the highest-quality welds on a wide range of metals. By reducing the risk of welding defects, hybrid laser welding improves the microstructure of the weld and its mechanical properties.

Close-up of Hybrid Laser-Arc Welds
Source: https://www.youtube.com/watch?v=wDIZabpSC1c

Industrial Applications of Hybrid Laser Arc Welding

The advantages of HLAW made it highly beneficial to various industries. That's specifically the case in applications that require higher weld speed and better weld quality than individual arc welding or laser welding.

Laser-MIG Hybrid Welding for Medium-Thick Plate Fabrication
Source: https://www.youtube.com/watch?v=JuwzOMTTS0o

As a result, hybrid laser arc welding is mainly used in the following industries:

Automotive Companies, such as Audi AG and Volkswagen, utilize hybrid laser arc welding in their production lines. They use the process to manufacture light vehicles and various metal components, including the main frame and the roof frame. The advantages of increased welding speed and wire efficiency, with good penetration and improved metallurgical characteristics, are particularly beneficial in the automotive industry.

Shipbuilding: Various companies utilize HLAW to construct ship panels and components. For thick steel panels and stiffeners, shipbuilders use a high-powered CO2 laser and a 450A MIG welding source to achieve desirable tensile strength, hardness, impact resistance, and bending strength, as well as fatigue resistance. Meanwhile, other companies use Nd: YAG lasers and MAG to avoid distortion and provide effective bridging of the joint gap. Fiber lasers also see increased use in the shipbuilding industry.

Laser Hybrid Welding in the Shipbuilding Industry
Source: https://www.linkedin.com/pulse/laser-hybrid-welding-shipbuilding-industry-/

Power industry: The advantages of HLAW, including process stability, higher joint gap tolerance, efficiency, and deep penetration, are particularly well-suited for power industry applications. Welders use the process to join components such as tight wall panels and ribbed pipes of boilers.

Pipeline industry: HLAW is ideal for thick-walled onshore and offshore pipelines. Process stability, deep penetration, higher joint gap tolerance, and higher efficiency are particularly suitable for pipe welding, especially in applications with varying thickness.

Hybrid Laser Arc Welding in Pipeline Welding Applications
Courtesy: Alabama Laser

Hybrid Laser Arc Welding Vs Arc Welding Vs Laser Welding

To help you further understand the fundamentals, we will compare the key parameters of the combined HLAW with those of the two single processes that comprise it: arc and laser beam welding.

Here is a quick comparison table of all three:

	Hybrid Laser Arc Welding	Arc Welding	Laser Beam Welding
Depth of Penetration	Deep penetration with filler support of arc	Moderate-to-deep penetration depending on the process	Very deep penetration, but with limited width
Welding Speed	Very high speed and productivity	Moderate to slow on manual processes	High welding speed
Gap Tolerance	Better than laser, but not as good as solely arc welding	Very high gap-bridging ability	Requires a tight and perfect joint fit-up to work
Heat Input and Control	Controllable heat input that is between arc and laser welding	Mostly high heat input with a wide heat-affected zone	Very controllable heat with narrow HAZ
Weld Quality	Stable arc and reasonable heat control produce exceptional welds with limited defects	Highly dependent on operator skill	High quality, but sensitive to contamination and imperfections
Operator Skill Requirements	Requires high-skilled workers familiar with both arc and laser welding	Moderate-to-low skill requirements, as it is widely available to welders	Requires special training, process, and equipment knowledge
Equipment Complexity	Very complex equipment that requires dual process coordination and precision alignment	Straightforward equipment that is easy to use and set up	Complex equipment that includes precise optics, shielding, and automation
Costs	Initially very expensive, but the benefits yield a fast ROI	Cheap and straightforward	Less expensive than HLAW, but more complex and costly than arc welding

Hybrid Laser Arc Welding vs. Arc Welding vs. Laser Welding

Hybrid Laser Arc Welding vs. Arc Welding vs. Laser Welding

Final Thoughts

Hybrid laser arc welding (HLAW) is a unique welding method that utilizes two heat sources: an arc and a laser beam. When combined, these two processes overcome the drawbacks of each individually and further highlight their advantages.

Fundamentally, arc welding is cheap, flexible, forgiving, but slower with more heat distortion. Laser welding is fast, precise, and offers deep penetration; however, it is costly and unforgiving, with potential gaps in the weld.

Hybrid laser arc welding combines deep penetration, filler metal, and improved gap tolerance, resulting in a swift, efficient, and high-quality welding process. As a result, this state-of-the-art process found its way into various applications worldwide, with notable highlights in the automotive, shipbuilding, power, and pipeline industries.

🧐What Is Hybrid Laser Welding? FAQ

1. Why combine laser and arc welding in HLAW?

Laser welding is fast and precise, but has poor gap-bridging ability. Arc welding is flexible but slower and causes more heat distortion. Hybrid Laser Arc Welding (HLAW) combines both to achieve deep penetration, higher speed, better gap tolerance, and improved weld quality.

2. What advantages does HLAW offer industrial users?

HLAW provides higher welding speed (up to 30% faster than laser alone), deep penetration, improved gap tolerance, wider thickness compatibility, lower operational costs, reduced heat input, and consistent high-quality welds with fewer defects.