Laser processing technology and hot stamping

In the past ten years, the technology of hot stamping body parts has evolved from a niche technology to an indispensable technology for applying high-strength steel to reduce weight. By applying this technology to high-strength steel, the weight of the vehicle is significantly reduced. Of course, the research and development work of steel manufacturers in the field of manganese-boron steel is a prerequisite.

Since the development of laser processing technology, its wide range of uses is needless to say. The application of laser processing technology in the hot stamping process chain is an indicator of the development of laser technology in higher fields. The development of laser processing The potential is huge.

Hot stamping is forging

Press and die apply external force to plates, strips, pipes and profiles, etc., to produce plastic deformation or separation, so as to obtain the desired shape and The forming and processing methods of workpieces (stamping parts) of different sizes. Stamping and forging are both plastic processing (or pressure processing), collectively known as forging. The blanks for stamping are mainly hot-rolled and cold-rolled steel plates and strips. Steels in the world , 60 to 70% are plates, most of which are stamped into finished products. The car body, chassis, fuel tank, radiator fins, boiler drums, container shells, motors, electrical appliances, iron core silicon steel sheets, etc. It is processed by stamping. There are also a large number of stamping parts in products such as instruments, household appliances, bicycles, office machinery, and living utensils.

From the perspective of users, these manganese boron steels and The improved coating usually poses new challenges for the hot stamping process chain, especially for laser technology. Compared with the previously used cold stamping steel, manganese-boron steel requires different processing conditions, and its different characteristics depend on the carbon content of each processing step, especially under the influence of heat, which requires corresponding process development.

In the steps downstream of the hot stamping process chain, parts need to be cut in most cases. Due to the high hardness and corresponding high wear resistance in the traditional mechanical fine-tuning operation, this operation should be performed in the unhardened microstructure area. In the past, such operations were generally not feasible, but lasers have been widely proven to be successful as a 'wear-free' tool, albeit with low yields. In other applications such as cutting the size of blanks, compared with the use of mechanical pressure, the use of laser cutting has many advantages

People use high melting point aluminum silicon (AS) coatings to protect steel in the furnace. However, this adversely affects the laser welding of metal deposits, so the coating must be removed before the welding process. In this case, the laser has proven to be a successful high-energy rate tool. In the production equipment, the Q-switched laser can completely remove the coating from the edge of the blank. In addition, the laser induced plasma spectroscopy (LIPS) process is used for quality monitoring. In this process, the Nd:YAG laser with a pulse length in the nanosecond range bombards the blank area to be removed from the coating, and spectroscopically analyzes the generated metal vapor plasma to determine the aluminum content. Another feasible method is to monitor the welding plasma during the subsequent laser welding process.

The use of laser technology has brought efficient solutions to the hot stamping process chain, which has greatly promoted the widespread use of hot stamping.