LASER 2022: LZH and LMB Automation develop laser system to process brass parts

27 Apr 2022

LaserMessing project is aiming to solve the copper-zinc alloy processing challenge.

by Matthew Peach in Munich

Brass continues to be used for many components, due to its good electrical conductance, hardness, and resistance to corrosion, but welding the copper-zinc alloy is challenging. Now Laser Zentrum Hannover wants to change this in partnership with LMB Automation, in Iserlohn, Germany.

In the project LaserMessing, the partners are developing a laser-based manufacturing system for automated production of brass components such as fittings, bearings, valves, turbines or heat exchangers.

The LZH scientists are working on a welding process that combines laser-based deep welding and cored wire processes. Their goal is a stable, automatable process with weld seams free of pores, weld spatters and underfill – for components with high aesthetic demands.

Seam quality

For this, the scientists of the group Joining And Cutting of Metals rely on a controllable method in combination with adaptable beam profiles, which unites the two processes. They use thermography and spectroscopy data to monitor the process to develop a process control system together with LMB.

Their aim is to target energy into the workpieces and reduce vapor capillary fluctuations. The process will be additionally stabilized by the use of core and ring spots. The subsequent laser cored wire process smooths the seam surface of the previously created deep welds for applications in the field of vision.

Laser beam welding of brass is in principle well suited for processing this alloy. The technique places only a relatively low thermal load on the workpiece and can achieve very narrow and deep seams. It is also very easy to automate, fast and precise, say the scientists.

However, processes specifically for joining brass alloys are often still affected by process instabilities. The alloyed zinc evaporates below the melting temperature of copper. For this reason, pore formation and a high hot cracking tendency of the seams occur.

A completed automated welding solution will enable LMB Automation to offer its customers welding processes for the series production of brass components and thus decisively expand its product portfolio.

LZH at LASER World of Photonics

Interested parties attending this week’s LASER World of Photonics exhibition can visit LZH in hall A5 at stand 210. Besides the brass welding capability LZH is presenting a number of other technologies, including:

• Approaches for integrated and miniaturized optics of the future.
• Lasers with special specifications for industry or for use in space
• Lasers for use in interaction with artificial intelligence for agricultural applications.
• Novel materials and application areas in additive manufacturing, such as natural fibers, glass, special materials like magnesium and titanium, and large component manufacture using laser deposition welding.
• Plants and system technology for individual challenges, using a combination of additive and subtractive manufacturing; and additive manufacturing in a low-oxygen environment.
• High-resolution broadband monitoring for coating processes
• Laser structured sensors.

Also on the LZH stand, visitors can find out how explosive ordnance can be defused more safely underwater using a laser-based system.