smartform® – enormous potential for cost reduction of complex components
15.06.2020 I Güllü Beydilli
In Europe alone, more than 20 million vehicles roll off the production lines every year, and almost 100 million worldwide. One thing is clear: At volumes like these, even small savings can have huge effects. thyssenkrupp Steel has developed an innovative process to production readiness which can achieve enormous savings in the manufacture of high-strength cold formed parts. But the two-stage deep drawing process known as smartform® offers further advantages: It reduces raw material requirements by up to 15 percent on average, improves quality and also reduces reworking and maintenance requirements. Per manufactured part, this can save between 10 and 15 percent in costs.
Project Manager Lars Bode: "smartform® shows its advantages with U or l-shaped components that are used in 60 places in the automobile. Typical applications are side skirts, A- and B-pillars, longitudinal and cross members as well as seat, window and roof struts. More than 90 percent of the body-in-white produced worldwide is made of steel, and at the same time the use of high-strength grades for these components is constantly increasing. The potential is enormous, because smartform® could make many components cheaper to produce worldwide."
Savings at all corners: The smartform® technology in detail
In contrast to the conventional deep-drawing process, in which the basic geometry of a component is created by deep drawing and further post-forming operations, smartform® relies on a two-stage process. In the first step, only a preform roughly adapted to the specific smartform® requirements is created. In the second forming step, the workpiece is brought to its final shape. Lars Bode: “At first glance, this looks like additional work. But in practice we have several advantages: In conventional deep drawing we have to counter the springback of high-strength steels with a high degree of expansion. For this we need sheet steel blanks with a drawing edge – i.e. an addition of material at the edges of the component where it is held during the pressing process. This material is not required with smartform®.”
Significantly less waste: more components from a coil
smartform® makes it possible for the first time to use a blank without a drawing edge and thus to reduce waste as much as possible. In figures this is how it looks: Significantly more components can be produced from a standard 25-ton coil – using a typical longitudinal beam as an example, 5,540 instead of the previous 4,870 end products. A further advantage: Depending on the load and the required crash behavior, a starting sheet about five percent thinner can be used in individual cases.
For customers, smartform® can also be simulated in advance via augmented reality:
Because the end product already conforms completely or very largely to the desired shape, the amount of post-processing required is also considerably reduced. Trimming of the drawing edges is completely eliminated, and the postforming steps otherwise required to compensate for the springback effect are also eliminated. Therefore, the edge trimming on the finally formed component is reduced to a minimum.
Particularly interesting for complex components
But that’s not all: Further cost optimizations result from the tool design and construction as well as the start of production – because the optimization cycles can be reduced by a factor of six compared to conventional processes. Even the conversion of an existing production line to smartform® can pay off – especially for components that are problematic from a dimensional accuracy point of view.
thyssenkrupp Steel offers vehicle manufacturers a complete service package for smartform® technology: In addition to potential analysis for specific applications, this includes in-depth analysis of promising components and the associated development of a specific forming process and process testing. These processes are also illustrated, for example, via augmented reality. The development engineers use a tablet to virtually carry the press weighing several tons to the customer in order to visualize the interaction between tool and component in three dimensions. The highlight is that the customer can view the forming process and the principle of action between material and die in detail and from different perspectives in 3D. In the end, the customer benefits from series production-ready, process-stable component manufacture at significantly reduced costs.