Additive manufacturing has exhibited continuous global growth in the field of technological development. Particularly, laser additive manufacturing (LAM) technology, which uses a laser as an energy-carrying beam and a metal powder or wire as raw materials, has become a hotspot in research and industrial applications.

AM PravaH® software has made a huge contribution to the production of high-performance metal-alloy components, with remarkable flexibility and dimensional precision. Among the most significant developments in this field, Wire Laser Additive Manufacturing, the technology that enables deposition of dense, microstructurally homogenous objects layer by layer with the uniform material integrity, is the most significant. The metal components produced with the help of AM PravaH® software have better mechanical properties that are mainly defined by improved strength and durability.

With the laser-induced wire melting method, the achieved thermal condition is very much controlled, giving a fine microstructural development and minimizing the usual defects such as porosity and inclusions. These components hence have high tensile strength, fatigue life, and hardness when compared to those produced traditionally. The process is successful in eliminating the typical manufacturing weaknesses, thus resulting in a strong mechanism and structural integrity. 

What is Wire Laser Additive Manufacturing (WLAM)?

Additive manufacturing has exhibited continuous global growth in the field of technological development. Particularly, laser additive manufacturing (LAM) technology, which uses a laser as an energy-carrying beam and a metal powder or wire as raw materials, has become a hotspot in research and industrial applications.

AM PravaH® software has made a huge contribution to the production of high-performance metal-alloy components, with remarkable flexibility and dimensional precision. Among the most significant developments in this field, Wire Laser Additive Manufacturing (WLAM), the technology that enables deposition of dense, microstructurally homogenous objects layer by layer with the uniform material integrity, is the most significant. The metal components produced with the help of AM PravaH® software have better mechanical properties that are mainly defined by improved strength and durability.

With the laser-induced wire melting method, the achieved thermal condition is very much controlled, giving a fine microstructural development and minimizing the usual defects such as porosity and inclusions. These components hence have high tensile strength, fatigue life, and hardness when compared to those produced traditionally. The process is successful in eliminating the typical manufacturing weaknesses, thus resulting in a strong mechanism and structural integrity. 

Wire Laser Additive Manufacturing (WLAM) is an advanced process of metal feedstock e.g., metal wire, which is melted selectively by a high-power laser to enable controlled material layering to achieve near-net-shape metal parts, built-up layer by layer. The WLAM module in AM PravaH® enables the user to perform detailed simulations of Wire Laser Directed Energy Deposition process with a focus on analyzing the melt pool dynamics.  

Key Process Parameters 

Some of the key parameters of the process are:

• Laser power

• Wire feed rate

• Laser Scanning speed

• Wire Radius

• Laser beam shape

• Spot Diameter

• Fresnel Coefficients

These parameters bring significant changes to the thermal profile, the melt pool dynamics and the solidification rates that ultimately influence the microstructural characteristics and mechanical properties of the final part obtained.

The ability to precisely control these parameters enables optimization of layer adhesion, density, and surface finish and therefore Wire Laser Additive Manufacturing is very well suited to the production of complex, high-performance geometries with custom microstructures that are highly desirable in the aerospace, automotive, and other industries that require structurally critical and reliable metal parts.

How does WLAM work?

WLAM stands for Wire Laser Additive Manufacturing. It is also referred to as Laser Wire Additive Manufacturing or Wire DED, depending on regional terminology. While the naming may vary, the core concept remains the same.

In this process:

• The energy source is a laser

• The raw material is metal wire

• The wire is melted in mid-air and deposited onto the substrate or previously deposited layers

• A 3D structure is built layer by layer, tailored to specific applications

Let me now show some animations demonstrating how the process works.

Process Parameter Optimization

Here, you can see a small cube being built. Such experiments are typically conducted in research environments to study defect formation and identify methods to eliminate them through process parameter optimization.

Once the correct parameters are established, the process can be scaled to large industrial components.

Unlike LPBF, which is limited by the size of the powder bed, WLAM allows the fabrication of large parts, often using robotic systems.

 At Paanduv Applications, we use AM PravaH to simulate isolated tracks, enabling users to determine optimal process parameters before actual manufacturing.

Let us briefly understand the working principle.

Here is the schematic of the process:

• A laser head provides the energy

• Optics focus the laser to a precise point

• A shielding gas prevents oxidation during melting and solidification

• A lateral wire feeder supplies the metal wire

• The part is built layer by layer

We observe the interaction between the laser, the wire, and the substrate.

Fundamental Physics is involved in the Process of WLAM 

The working principle involved in this process is the phase changes that occur, like from solid to liquid and then again with solidification, it converts back into a solid and it changes a lot of the material properties during this process. 

There is the laser dynamics that is involved, like how the laser interacts with the material. It's not the same for every material, as it depends on the composition that you have in your alloys to see if it's weldable or not. 

There is a mass and heat transfer that is occurring that is temperature-dependent surface tension. So the meltpool has a liquid metal, and depending on the temperature of the meltpool, there are some other forces that are acting on it that define the whole solidification process.

 The next comes the Marangoni convection that shows how the meltpool is not just a steady state, it's actually an evolving state where liquid is swirled around, and it's transported from one point to another, like in a very small area and volume.

Here, you can also see how Marangoni convection is also simulated using AM PravaH®.

All of these effects are accurately captured using AM PravaH simulations.

Now, let us discuss current trends in WLAM, both in industry and research.

Current Trends of WLAM in Industry and Research

Current trends of WLAM in industry and research.  It is a sustainable technology that is catering towards industry 4.0.  It's also focusing towards reducing material wastage, which can also help in the circular economy.  It is achieving near shapes that are dense in nature, and with these facts in hand, we can produce large components.

In the end, it's like a 3D printing process, so we have greater freedom of part design, and we are not limited by the conventional manufacturing processes at hand. We use wire feed stock, and this allows high deposition efficiency and high deposition rates.  It allows a really good transfer of energy to the substrate so that we have a metallurgical bonding that is with the substrate and the deposit. Then there is smoother meltpool dynamics, which give us a stable microstructure and in the end, with all of this combined,d we have robust components at hand.  

Current Industrial & Research Applications of WLAM

WLAM is widely used in research and development (R&D) to understand and optimize the process before industrial deployment. In this phase, isolated tracks are analyzed to study melt pool behavior, bonding quality, and track geometry, allowing researchers to identify and eliminate defects such as lack of fusion, porosity, and instability. By systematically varying process parameters like laser power, wire feed rate, and travel speed, stable operating windows are established, enabling process optimization for scalability in multi-track and multi-layer builds.

In industrial applications, WLAM is used to manufacture propellers, gear wheels, and structural components, which can be directly utilised after post-processing such as machining or surface finishing. One of the most critical applications is repair, particularly for forming tools and gas turbine blades, where wear significantly reduces service life. 

WLAM enables precise material deposition to restore damaged regions, extend tool life, and improve sustainability, while also allowing controlled microstructure restoration in high-performance components such as turbine blades, often in combination with LPBF for enhanced precision.

Common Defects in WLAM

Despite its advantages, the adoption of WLAM is challenged by the formation of several process-induced defects, some of them is already tested by many researchers, and that can also be shown in AM PravaH, like vapour entrapment. You can see in figure 1.1, a small bubble that is inside of the inside of the melt pool. 

In the next figure 1.2, you can see grooves that are present depending on the manangi convent convection and the solidification rate,  material solidifies at different rate and this can lead to the formation of these groups.  

In Figure 1.3, you can see that there is a droplet liquid transfer, which is happening because of a lack of laser power. 

There is also one last defect, like a hump, that is that can be considered as a non-uniform material deposition that is actually also shown through the results of the simulation. 

These defects highlight the importance of precise process control and reinforce the need for physics-based simulation tools like AM PravaH to predict and mitigate such challenges before physical manufacturing.

Scan Strategies 

There are many scan strategies that you can use. Here are some scan strategies that are mainly used. I just listed out some examples here. It depends on the person or researcher who has deposited the 3D structure, whether they want to use the whole structure or just try different layers and conduct research on that. 

• Z pattern for multitrack simulation 

• Single-layer L-track simulation 

• Single-layer bi-directional scan pattern 

• Rectangular scan pattern simulation  

• Single Leyer Multi-TRACK SIMULATION 

• Single Layer, Single Track Scan Pattern 

How AM PravaH helps simulate WLAM 

The WLAM module in AM PravaH® enables the user to perform detailed simulations of the wire Laser Directed Energy Deposition process with a focus on analyzing the melt pool dynamics and bead morphology.

With the laser-induced wire melting method, the achieved thermal condition is controlled, giving a fine microstructural development and minimizing the usual defects such as porosity and inclusions. These components hence have high tensile strength, fatigue life, and hardness when compared to those produced traditionally. The process is successful in eliminating the typical manufacturing weaknesses, thus resulting in a strong mechanism and structural integrity.

Key industries

• Automotive sector for large engine blocks, transmission housings, brake discs, structural chassis parts, and tooling dies.

• Aerospace & Defense sector for large turbine casings, wing spars, landing gear components, rocket nozzles, and structural panels.

• Healthcare sector for customized orthopedic implants, large joint replacements, prosthetic components, rehabilitation aids, and surgical tooling.

Why model WLAM with AM PravaH®

• Accelerating material innovation.

• Mitigating part defects such as non-uniformity, lack of fusion & heat accumulation.

• Optimizing process parameters and modes of molten metal transfer: globular, liquid bridge, and unstable transfer.

• Reducing development cost and resources.

Software Features of WALM Module of AM PravaH Software

• Accurately captures process dynamics by simulating actual wire movement.

• Molten metal deposition at different wire feed angles, feed rates, and variable laser power with a controllable spot diameter.

• Capable of simulating Multitrack multilayer deposition of metal alloys.

• Alloy and process-specific optimal numerical settings.

• Leveraging capabilities by AI-based learning and quick predictions.

Physics Captured in WLAM Module of AM PravaH Software

• 4-phase multiphase, including vapour and shielding gas interactions.

• Augments temperature-dependent properties to model Marangoni convection and phase change.

• Laser-material interaction with multiple reflections and absorption based on material and laser type.

• Captures different modes of metal transfer, such as liquid bridge and droplet transfer, along with bead morphology.

Laser-Wire Deposition vs. Powder-Based Techniques:

Laser power bed fusion (LPBF) and Wire Laser Additive Manufacturing (WLAM) are the two most differentiated techniques among the other additive manufacturing methods. Each has its strengths, although there are some strong arguments why wire-laser additive manufacturing is usually better than the other in most industrial uses. 

• Efficiency and Speed:- The WLAM module can also be more efficient and faster due to the use of continuous wire feed as raw material, which can result in higher deposition rates than the layer-by-layer method of powder-based techniques. This equates to shorter build duration and increased productivity, and thus it is best suited to the production of large parts or prototypes with a shorter deadline. This higher deposition efficiency is useful in high-scale parts or for the rapid prototyping process, where time is limited and where there is a possibility of working on large surfaces of several meters. 

• Material Waste:- One of the significant advantages of the AM PravaH® wire laser process is its efficient use of raw material. With powder-based systems, a considerable amount of unused powder often gets wasted, or to prevent wastage, it needs to be recycled, which can be time-consuming and costly.

Manufacturing parts with WLAM tends to produce smoother surface finishes with fewer defects, as there is less risk of porosity and other powder-related issues. This can result in fewer post-processing steps, less computational time, and reduced overall production costs.

• Operator Safety and Material Handling:- Handling metal powders comes with inherent risks, including inhalation hazards and the potential for dust explosions. Powder-based systems require stringent safety measures like proper protective gear and ventilation systems and specialized equipment to mitigate these risks. On the other hand, the laser-wire method uses welding wire, which is inherently safer to handle and reduces the need for extensive material handling safety protocols.

• Material: The cost of metal alloy powders can be significantly higher than that of metal wire, primarily due to the manufacturing processes involved in creating fine, uniform metal grains.

However, when compared to traditional subtractive manufacturing methods like CNC machining, which typically results in substantial material waste, additive manufacturing uses only the necessary amount of raw material.

• Applications & Versatility:-Wire laser DED process is versatile and can be applied in various industries. It is particularly useful for repairing parts or applying protective coatings, such as in the defense, aerospace, and oil & gas industries. It is also well-suited for the fabrication of very large-scale parts, which can be challenging with powder-based techniques due to smaller size limitations and stringent time constraints.

• Environmental Impacts: Reduced waste and lower energy consumption associated with  AM PravaH® WLAM module contribute to a smaller environmental footprint than a powder-based solution. With powder requiring a great deal of energy and resources to manufacture and its toxicity to humans, laser powder bed fusion is not considered a sustainable choice.

As industries increasingly focus on sustainability, the ecological benefits of Wire Laser Additive Manufacturing become an essential consideration.

While both wire-laser and powder-based 3D metal printing have their place in manufacturing, the WLAM module of AM PravaH® offers several advantages that can make it a superior choice in many scenarios. Its efficiency, cost-effectiveness, safety, and versatility make it an attractive option for manufacturers looking to optimize their large-scale production processes and compete in the market.