Laser welded blanks (LWBs) enable carmakers to reduce the weight of a monolithic part. At the same time, the strength or safety performance of the part can be maintained or improved, depending on the combination of steels selected.
During the blanking step, laser welded blank shapes can be arranged to make maximum use of the steel. Known as ‘nesting’, this technique increases the number of parts that can be made from one sheet of material. Less steel is required, and less scrap is produced.
The right steel grade is in the right place, in the right thickness to create a tailor-made solution for each part.
Depending on the shape, scrap rates can be as low as seven percent. With lower scrap rates, cost efficiency is increased significantly.
This compares very favorably to the scrap rate for monolithic parts which can be one third or higher.
ArcelorMittal Tailored Blanks can work with an OEM’s design department to determine if a part is suitable for nesting. The assessment includes an assessment of the technical requirements for the part and a cost analysis to achieve the most economical solution.
Using LWBs, the technical performance of a part can be enhanced significantly without adding to the weight of the vehicle.
Examples of improved technical characteristics include:
OEMs can simplify their production processes with LWBs thanks to:
LWBs are a clever way to significantly reduce the mass of a part or the body-in-white of a vehicle. Thanks to the very high strength of modern automotive steels, very thin gauges can be utilized. Using some of the most advanced high strength steels, weight savings of 10 to 20 percent (or more) can be achieved for a single part.
The weight savings occur because:
By ensuring the right material is in the right place, in the right thickness, LWBs can significantly reduce the weight of a part.
The following image shows the example of a door ring. The LWB solution on the right can be up to 20 percent lighter than the multi-part door assembly shown on the left.
In traditional vehicle assembly, different parts were overlapped to ensure a strong join. With LWBs, overlaps are eliminated in many parts. Instead, the two parts are butt welded, reducing the amount of material used and the overall weight of the part. When combined with thickness optimization, excellent weight savings can be achieved.
The development of LWBs has had a direct impact on improving automobile safety since they were first introduced in the 1990s. This is because LWBs combine the energy absorption and anti-intrusion properties of different grades of steel in one part.
Evolution of LWB use:
Example: Improved crash performance with hot stamped LWB door ring