Application of metal laser cutting machine in cutting aluminum

The advantage of laser cutting is that it can quickly and accurately process aluminum foil into different shapes. This technological advantage makes laser cutting equipment attractive to many airlines as soon as it is commercialized. In the 1970s, major manufacturers evaluated laser cutting technology, and they found that the damage to the fatigue characteristics of parts caused by micro-cracks produced by laser processing was not allowed. The potential increase in weight damages the interests of the manufacturing industry, making laser cutting technology shelved by major airframe manufacturers.

The manufacture of spinner parts and transmissions is made from large metal billets. The fuselage also contains some parts using forged materials, but most of the fuselage parts are made of aluminum plates. Traditionally, 7000 series zinc-based aluminum alloys are used for processing, because the alloy has good static strength and fatigue strength. Although the 7000 series aluminum materials are very suitable for aerospace applications, they are not resistant to high temperatures. Rapid heating, such as welding and laser cutting operations, can cause micro-cracks. Micro cracks lead to a decrease in fatigue strength. Welding and laser cutting are two processes that produce thermally induced microcracks.

Quality and processing control are crucial. Any process that brings uncertain factors to processing must be controlled or eliminated directly. In the past, laser cutting has brought huge challenges to the quality control and consistency between different production batches.

In the current laser cutting system, the limitations of these laser cutting in aviation applications have been improved. These limitations include fatigue performance and reduced manufacturing process consistency. Now, the laser system has greatly reduced the size of the heat-affected zone (HAZ) and the corresponding microcracks. In the laser cutting process, technicians can already control the cutting parameters, and use calculator software to perform precise repetitions. These technological advancements make people rethink whether laser cutting is suitable for the production of fuselage structures. The fuselage structure is mainly made of 7000 series aluminum material.

Fatigue fracture usually occurs in places where stress is concentrated, such as the edges of parts, changes in geometry, or joints. There are many different ways to join the fuselage parts made of sheet metal, and most of the fatigue cracks occur at the joints. If the laser is not used to cut the small holes in the joint, the laser is mainly used for edge cutting of the part. For other effects, the most vulnerable connection position can be used to illustrate that compared with the connection, the microcracks caused by laser cutting are not the main damage location. In this way, we can conclude that if a part is likely to break at the joint, then laser cutting technology will not further damage the fatigue characteristics of the part.

The laser cutting process can process consistent parts faster, and it is more efficient than traditional processing. Laser technology is expected to reduce processing time and production costs. For a long time, in the processing of 7000 series aluminum plates, the advantages of lasers have not been brought into play due to the reduction of fatigue performance. Recently, innovations in laser systems have allowed people to reassess the advantages of laser cutting aluminum for aviation. Preliminary tests have shown the potential of laser technology in airframe processing. Future airframe systems and existing designs should not rule out the possible application of lasers in this airframe system based on past experience. We should keep an open attitude to analyze various situations to determine whether laser technology can bring product benefits.