All You Need to Know about Laser Welding Machine

Laser welding machines are increasingly gaining popularity due to their ability to weld materials precisely and accurately without risking distortion or warping of nearby material.

This blog post will help explore all aspects of laser welding machines, from understanding how they work and which materials can be used to what types there are, as well as their benefits along with common techniques and best practices when choosing a system best suited to your needs.

Let’s start!

What is a Laser Welding Machine?

Laser welding machines are specialized tools used in industrial settings for various joining techniques. The technology combines high-powered laser beams and materials manipulation to provide a powerful alternative to traditional welding methods.

Laser welders take advantage of laser light's unique properties, including its ability to generate very focused and intense heat energy when directed at an exact point on a workpiece metal surface.

This allows the welder to make extremely precise cuts while avoiding excessive heat being transferred to nearby parts, resulting in more precise joints with minimal material damage or distortion compared with other welding styles.

And since lasers operate within narrow wavelength ranges, they can also be adjusted precisely according to the type of material being worked on for optimal performance results, an additional factor contributing greatly towards achieving higher-quality finished products.

How Does Laser Welding Machine Work?

• Laser welding works based on the principle of heat generation by the laser source. A high-power density laser is used to apply heat to a joint between two metal surfaces.
• This concentrated heat source is created by diode lasers that produce light directed through lenses, mirrors, and fiber optics in laser welding.
• During the process, the weld will form from a mixture of base metals and molten material from the heating effect of the laser's energy.
• The power and duration of this energy can be adjusted depending on factors such as material thickness but typically tends to be 0.1 second or less to achieve maximum accuracy.
• By using specially designed optics and software, operators can accurately position and control the beam's intensity for optimum weld conditions.
• With no physical contact between materials during welding, there are minimal chances for contamination or damage to both parts being joined.

What Materials Can Be Used for Laser Welding Machines?

Laser welding machines can be used on a wide range of materials, such as plastics and metals, making it an incredibly versatile process.

Commonly used materials include titanium, aluminum alloys, copper alloys, nickel-based superalloys, steels (mild steel to high-strength low alloy), and precious metals including gold and silver.

Different laser sources are suitable for different weldable materials; Nd: YAG or disk lasers are generally most suited for metals, while CO2 is better at thermal plastic welding.

Fiber lasers also offer excellent performance when working with ferrous or non-ferrous metals thanks to their combination of power levels in the kW range and precise beam delivery system that minimizes heat input.

What are the Parts of a Laser Welding Machine?

Laser welding machines typically have three primary components - a laser source, an optics system to direct and focus the light, and a workpiece handling or positioning mechanism.

Each component is critical for successfully controlling the welding process and ensuring high-quality results.

Laser Source

The laser source is the core component of a laser welding machine and is responsible for generating the intense beam of coherent light used in the welding process.

This source typically employs a laser medium, such as a gas, crystal, or semiconductor, which is stimulated to emit photons.

Common types of lasers used in welding include solid-state lasers, fiber lasers, and CO2 lasers. The choice of laser source depends on the specific requirements of the welding application, such as material type, thickness, and desired precision.

Optics System

The optics system is important in precisely shaping and directing the laser beam onto the workpiece. It comprises various optical components like lenses and mirrors that focus and steer the laser beam.

The goal is to concentrate the laser energy at the desired location on the workpiece, ensuring optimal weld quality and accuracy.

The optics system also helps control factors such as beam diameter, focal length, and spot size, which are critical for achieving the desired welding results.

Workpiece Handling and Positioning

This component involves the mechanisms responsible for holding, moving, and positioning the workpieces during welding.

Proper handling and positioning are essential to ensure that the laser beam accurately targets the intended welding area.

Workpiece handling systems may include robotic arms, CNC (Computer Numerical Control) systems, or other automated devices.

Precise control of the workpiece's position and orientation is essential for achieving consistent and high-quality welds.

Additionally, these systems may integrate features like rotation, tilt, and translation to accommodate various welding scenarios and geometries.

Types of Laser Welding

Laser welding is capable of joining materials in an extensive range of ways, from precise spot welds to deep-penetration butt joints and lap seams.

Common types of laser welding include tailor welding, fillet welding, stitch welding, and lap welding.

Tailor Welding

Tailor welding is also known as tailored blank welding. This autogenous welding technique enables the user to tailor the process for joining materials with varying thicknesses and even dissimilar materials.

The laser is precisely controlled to adjust its intensity and focus along the weld line, creating a tailored joint suitable for specific applications.

Fillet Welding

In fillet welding, the joint is created in the form of a fillet, which has a triangular cross-section. This type of welding is often used to join two perpendicular surfaces.

Fillet welds are commonly employed in construction, shipbuilding, and various structural applications to create strong and durable connections.

Stitch Welding

Stitch welding involves making a series of intermittent spot welds along the joint rather than a continuous weld. This method minimizes heat input and distortion in the materials being joined.

Stitch welding is suitable for thin materials or components where controlling heat is critical, such as fabricating sheet metal parts or electronic components.

Lap Welding

Lap welding, also known as overlap welding, is a process where two overlapping pieces of material are joined together. The laser melts and fuses the overlapped sections, creating a strong bond.

Lap welding is often used to assemble thin sheet materials, like in the production of metal containers, where a continuous and leak-proof joint is essential.

Benefits of Laser Welding Machine

Laser welding machines offer many advantages, including improved accuracy and weld quality, increased speed, low thermal distortion, material versatility, and more.

Read further to learn more!

Easy to Use

Laser welding machines are user-friendly and integrate well with automation and CAD systems, enabling easy control and high precision. Non-contact tools like fiber lasers require low maintenance, saving time and ensuring efficiency.

Minimal Heat Affected Zone (HAZ)

Laser welding technology minimizes the heat-affected zone, reducing distortion and ensuring good weld quality.

Newer models provide high welding speeds, further decreasing HAZ compared to traditional methods, making it ideal for delicate applications like medical device manufacturing.

High Precision and Accuracy

Laser welding delivers precise results with almost zero deviation from the intended target, suitable for applications where accuracy is crucial. It produces high-quality welds with minimal post-processing, offering cost advantages over traditional methods.

Thickness and Material Versatility

Laser welders excel in working with thin metals, generating rapid and powerful heat concentrated on a small area.

Modern laser systems accommodate various materials and thicknesses, allowing for versatile welding techniques and the ability to work with multiple materials using one machine.

Reduced Distortion and Warping

Laser welding minimizes distortion and warping through shorter heat input, producing less thermally induced stress on metals. This makes it suitable for precision fabrication projects, especially in industries like automotive and aerospace manufacturing.

Scale Up Production

Laser welding machines contribute to increased production and quality assurance with faster cycle times than traditional welding methods.

High power-density laser sources enable larger scale production cycles, offering advantages over conventional techniques in speed and precision.

Improve Weld Quality

Laser welding provides high-quality welds with greater precision, accuracy, and reduced distortion than traditional welding methods. It offers better control over joint penetration, dimensional stability, and accuracy, minimizing post-processing costs.

High-efficiency

Laser welding machines operate efficiently without physical contact, transferring energy through laser beams. This non-contact operation reduces distortion, warping, and vibration, producing precise connections with minimal energy consumption.

The low heat input also minimizes the heat-affected zone, reducing cleanup and preparation work commonly associated with other welding methods.

How to Choose a Laser Welding Machine?

• Choose the type of laser technology you need. Different types of lasers have distinct characteristics. Fiber lasers are often preferred for welding metals, CO2 lasers for non-metallic materials, and solid-state lasers for precision applications.
• Consider the power requirements based on the thickness and type of materials you'll be welding. Higher wattage is generally required for thicker materials.
• Check the beam quality. A smaller, more focused laser beam provides higher precision, which is essential for intricate welding tasks.
• Higher pulse frequencies can increase welding speed, which is crucial for production efficiency.
• A user-friendly interface simplifies operation, reducing the learning curve for operators.
• Consider whether the machine can be integrated into automated production lines for increased efficiency.
• Efficient cooling is crucial to maintain the laser's performance. Water cooling systems are common, and their effectiveness should be evaluated.
• Assess the frequency and duration of required maintenance tasks. Minimizing downtime is critical for productivity.
• Ensure the machine has adequate safety features, such as enclosures and interlocks, to protect operators from laser radiation.
• Different lasers are suitable for different materials. Ensure the laser welding machine is compatible with the materials you'll be working with.
• Check the stability and control of the laser beam for consistent and high-quality welds.
• Consider not only the initial purchase cost but also ongoing expenses, such as maintenance, energy consumption, and consumables.
• Choose a reputable supplier with good customer support and service to address any issues that may arise.
• Consider the available space in your facility and choose a machine that fits comfortably.
• Ensure that the laser welding machine complies with safety standards and regulations in your industry and region.

Difference Between Laser Welding Machine Vs Traditional Welding.

Laser welding machines and traditional welding techniques are fundamentally different in their approach to joining materials.

Here’s a comparison table:

What Are the Common Traditional Welding Techniques?

MIG (Metal Inert Gas) Welding

MIG welding, also known as Gas Metal Arc Welding (GMAW), uses a continuous and consumable wire electrode to create an electric arc between the electrode and the workpiece.

This arc produces heat, which melts and fuses the metals together, forming a strong and durable weld.

Stick Welding

Stick welding, also known as Shielded Metal Arc Welding (SMAW) or manual metal arc welding (MMA), uses an electrode with a flux coating to join metals.

The process gets its name from the stick-like electrode that is used. The electrode consists of a metal core wire and a flux coating that provides a protective gas shield and forms a slag to protect the weld pool.

TIG (Tungsten Inert Gas) Welding

Also known as Gas Tungsten Arc Welding (GTAW), this process utilizes a non-consumable tungsten electrode that delivers current while allowing operator control over precise filler material addition into molten metal weld puddle created by electricity between workpiece and tip of pointed tungsten rod.

Flux-cored Arc Welding (FCAW)

Flux-Cored Arc Welding (FCAW) uses a continuous tubular electrode filled with flux to join metals. It is a variation of the more traditional Shielded Metal Arc Welding (SMAW) or Stick welding.

FCAW is considered a semi-automatic or automatic welding process, and it can be performed with or without the use of an external shielding gas.

Gas Welding

Gas welding uses fuel gas and oxygen to produce a flame that heats the workpieces to be joined. The flame's heat melts the workpieces' edges, allowing them to fuse together when cooled.

This process is commonly used for joining metals, particularly in applications requiring precise control over the welding temperature.

Resistance Welding

Resistance welding joins materials by applying pressure and passing current through the materials. The heat generated by the electrical resistance of the materials causes them to melt and fuse together.

Plasma Arc Welding (PAW)

Plasma Arc Welding (PAW) is an advanced welding process that uses a constricted plasma arc to join metals.

It is similar to Tungsten Inert Gas (TIG) welding but with the addition of a constricted plasma arc. The process was developed to improve the precision and control of the welding arc.

Spot Welding

Spot welding is a type of resistance welding process used to join two or more metal surfaces together at specific points. The process involves applying pressure and electrical current to the metal sheets or parts to create a localized weld at the points of contact.

Applications of Laser Welding Machine

Laser welding is an increasingly popular process in different industries due to its speed, accuracy, and versatility. Here’s a list of some common applications:

Automotive Industry

• Body and Frame Construction
• Exhaust System
• Battery Manufacturing

Aerospace Industry

• Turbine Components
• Spacecraft Construction
• Sheet Metal Fabrication

Electronics Industry

• Microelectronics
• Connectors and Cables
• Battery Packs

Medical Device Manufacturing

• Implantable Devices
• Medical Instruments
• Dental Devices

Conclusion

Laser welding machines are an effective and versatile metal joining technology with many advantages over traditional welding techniques. They can be used for various applications, from automotive to aerospace and medical device manufacturing.

Laser welders offer high precision and accuracy, minimal heat-affected zone (HAZ) production, and reduced distortion compared to traditional methods. The laser beam is extremely powerful yet cleanly concentrated on the weldment joint, requiring less filler than traditional techniques.

When selecting a laser welding machine, consider your specific application needs, the size of parts being joined, the types of materials that need to be worked on as well as budget considerations when deciding which type is best suited for your project or business needs.

Regardless of what you choose, laser welding systems provide highly reliable results whenever needed.

DEK is a global professional parts machining manufacturer. We have first-class laser welding technology. If your project is ongoing,  contact us today!