Press hardening using masks during furnace process for partial austenitization

应用研究项目的重点是开发和实现用于生产部分回火钢板金属部件的掩蔽概念。这个概念的基础涉及硼锰钢22MnB5的材料模型增强。在加热过程中，必须考虑材料结构的部分奥氏体化，以便有目的地调整构件的性能。在炉内使用掩模体应避免或降低部分空白区域的奥氏体相变。因此，在热冲压工艺后，组件应具有有利的、局部变化的性能。通过这种方法，可以优化硼锰组件或车身结构的碰撞性能。炉膛停留时间是由通常使用的炉渣保护涂层渗入基料所需的时间来决定的。在此期间，掩蔽体必须降低温度的升高。为了以确定的方式调整组件属性，需要一种适当的屏蔽体设计方法。因此，模拟模型必须同时考虑掩模体的热力学性能和能够计算在炉内停留时间内毛坯部分奥氏体化的材料模型。通过这种方法，可以预测由于热冲压过程而引起的局部部件性能变化。

The applied research project focusses on the development and realization of a masking concept for producing partial tempered steel sheet metal components. The basement for this concept involves a material model enhancement for the boron-manganese steel 22MnB5. Partial austenitization of the material structure during the heating processes has to be considered to enable a purposeful adjustment of the component properties. Using masking bodies in the furnace process the austenitic phase transformation should be avoided or lowered in partial blank areas. Thus, the component should feature advantageous, local varied properties after hot stamping process. By this means, the crash-performance of the boron-manganese components or rather of the car body structure can be optimized. The furnace dwell time is predetermined by the time need of the usually used cinder protection coating to permeate into the basic material. During this time, a masking body has to lower the temperature increase. To adjust component properties in a defined way an appropriate method for masking bodies design is required. Therefore, simulation models have to consider both the thermo-mechanical properties of the masking body and a material model which is able to compute a partial austenitization of the blanks during furnace dwell time. By this means, it would be possible to predict the local varying components properties due to the hot stamping procedure.