Investigation of diffusion behavior of carburized sheet metal in hot stamping
Investigation of diffusion behavior of carburized sheet metal in hot stamping
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DOI：
10.1051/matecconf/201819008004
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发表时间：
2019
影响因子：
2.5
通讯作者：
A. Horn;M. Merklein
中科院分区：
文献类型：
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作者：
A. Horn;M. Merklein
今天，车身结构件的制造面临着几个挑战，比如成型精度、乘客安全和轻量化设计。满足这些部分竞争需求的一种可能性是应用烫印部件。热成形和模内淬火的结合不仅减少了回弹，还导致了超过1500兆帕的拉伸强度。除了传统的烫印工艺外，该工艺还可以适用于制造具有定制性能的零件。这些最先进的工艺最大的问题之一是由于热传递而形成广泛的过渡区。利用最小的过渡区来调整力学性能的一个有希望的方法是对金属板材进行量身定制的渗碳。因此，零件局部涂有石墨，进行热处理，然后淬火。本文研究了碳扩散的时变过程。对两种不同厚度的板材进行渗碳和淬火。用单轴拉伸试验和显微硬度测量对所得力学性能进行了分析。在此基础上，识别过程窗口。此外，本文还对EDX和WDX分析在碳浓度测量中的适用性进行了研究。
Today, manufacturing of structural car body parts faces several challenges, like forming accuracy, passenger safety and lightweight design. One possibility to fulfill these partially rivalling demands is the application of hot stamped components. The combination of hot forming and in-die quenching reduces not only springback, but also results in tensile strengths of more than 1500 MPa. Besides conventional hot stamping, the process can be adapted to manufacture parts with tailored properties. One of the biggest issues of these state-of-the-art processes is the formation of extensive transition zones due to heat transfer. A promising approach to adjust the mechanical properties with a minimized transition zone is tailored carburization of sheet metal. Therefore, the parts are locally coated with graphite, heat treated and subsequently quenched. In this work, the time variant process of carbon diffusion is investigated. Sheets with two different thicknesses are carburized and quenched. The resulting mechanical properties are analyzed using uniaxial tensile tests and microhardness measurements. On this basis, a process window is identified. Furthermore, the applicability of EDX and WDX analysis for the measurement of carbon concentration is investigated within this work.