What is the difference between laser cladding and laser welding?

Both processes have their own advantages, but they also work well together – and future developments may lead to more efficient applications; laser cladding and laser welding are different processes, but they serve similar needs: Connection materials. Each has some features and benefits, and in some cases professionals can use them all simultaneously. Let’s take a look at what each process is and what it offers. What is laser cladding? —Laser cladding, also known as “laser deposition,” involves the use of filler materials to create a metallurgical bond between a metal substrate and a metal coating. The filler material usually arrives in the form of powder, ribbons or wires, and the heat of the laser is introduced coaxially or laterally. By using multiple powder types and adjusting the feed rate for each powder, it is possible to create components deposited with multiple materials, or even components with material gradients. Laser cladding plays a role in a wide variety of industrial tasks – including applying surface coatings, rapidly manufacturing and repairing worn parts. CO2, Nd:YAG (neodymium-doped yttrium aluminum garnet), and fiber lasers are three lasers used in this process and are used for several reasons: Due to the metallurgical bonding, the risk of separation and delamination is very low. Laser cladding supports a variety of material options, including substrate and deposition materials. Porosity is limited using this method. Laser cladding is also well suited to automation and integration into CNC operations and CAD-based processes. Deposition material options include ferrous metals such as stainless and carbon steel, as well as cobalt- and nickel-based alloys, as well as aluminum, Inconel and titanium alloys. Compared to traditional cladding and welding techniques, laser cladding provides high-speed thermal cycling, allowing for higher hardness and finer microstructure – two properties that help resist corrosion. Laser cladding also offers the benefit of a limited heat-affected zone, which has many advantages: It reduces the amount of trauma to the part or workpiece, reduces the potential for deformation, and allows the process to be performed with other critical areas that are less heat-resistant , including adjacent edges and walls. This means laser cladding can add structural reinforcement to sensitive areas. For an example of laser cladding and its benefits, compare laser cladding screws vs. nitrided screws. According to the “Laser Welding Technology Manual”, the service life of screws treated with laser cladding is 60% longer than similar high-alloy nitrided screws. Heavy industries such as oil and gas and underground mining are great candidates for laser cladding—workers often use it to rebuild cylinder struts, drilling equipment, turbine blades and other critical components. By doing so, they extend the performance life of these critical components and extend the service life of their equipment.

What is laser welding?

—Laser welding is a process in which a laser melts two different materials together. It can be used to connect tiny electronic components as well as larger steel structures. The most common laser types used here are CO 2 – delivered through mirrors – and Nd:YAG – delivered through optical fibers. However, due to its higher power output, CO 2 lasers can join thicker steel plates—up to 1.5 inches thick—that Nd:YAG lasers cannot. The fundamental difference between laser welding and laser cladding is that it does not require filler materials. For applications that require joining disparate materials, manufacturers can include interlayers with IR-absorbing properties. Like laser cladding, laser welding also produces a minimal heat-affected zone and little thermal deformation. Other advantages include high productivity and high-speed operation. Because the laser provides a concentrated source of heat, the joint between the two materials quickly melts and fuses, followed by cooling. This makes the choice of materials a critical decision for manufacturers, as these materials must be able to withstand rapid cooling without cracking. Laser welding is common in a variety of applications, including: electronics packaging; textiles; medical devices; window frames; signage and visual displays; packaging of food and medical products; automotive parts. For example, why are manufacturing and/or maintenance personnel taking laser welding so seriously? , consider the difference between using laser welding to repair molds versus tungsten inert gas (TIG) welding. Pulsed laser welding reduces collateral damage and weakening of the area surrounding the weld. This allows molds or other workpieces to be repaired or reused much more often and over a much longer period of time than workpieces repaired using traditional welding.
Cladding and Welding Together — Laser welding and laser cladding differ in some ways. They both join two materials together, but laser cladding essentially creates a new surface by coating the base material with another metal. At the same time, laser welding fuses the two workpieces together. However, in some cases, the two can work together.

One situation that combines the two involves the use of “exotic” metallurgy. Some austenitic steel grades and nickel alloys are “exotic” and desirable because of their ability to withstand corrosion in harsh environments. Welding exotic materials that don’t occur naturally can be difficult, but using both welding and cladding can help achieve the best of both worlds. Laser welding can join two traditional materials valued for their structural properties, while laser cladding can strategically deposit more exotic materials valued for their surface properties at critical joints or locations where severe wear occurs. One example is mining truck wheels. Mining companies can breathe new life into these structural components by strategically covering the most worn areas. Welding traditional materials creates the structure of the part itself, but aftermarket cladding using special alloys during maintenance or repair can help extend its life by imparting desirable qualities to the surface, such as corrosion resistance. Another use case that combines the best of both worlds involves thick plate welding, which typically requires a labor-intensive process called joint preparation. However, hybrid laser welding borrows from laser cladding by introducing filler material, which makes much of the preparation unnecessary. The two processes are beneficial individually for a variety of reasons, but they can also work well together in certain situations. Future developments may bring more hybrid approaches that combine the most effective features of both.