Opěla Petr, Schindler Ivo, Kawulok Petr, Kawulok Rostislav, Rusz Stanislav, Navrátil Horymír, Jurča Radek
Faculty of Materials Science and Technology, VSB-Technical University of Ostrava, 17. listopadu 2172/15, 70800 Ostrava-Poruba, Czech Republic.
Třinecké železárny, a.s., Průmyslová 1000, 739 61 Třinec-Staré Město, Czech Republic.
Materials (Basel). 2020 Aug 7;13(16):3480. doi: 10.3390/ma13163480.
In the presented research, conventional hot processing maps superimposed over the flow stress maps or activation energy maps are utilized to study a correlation among the efficiency of power dissipation, flow stress, and activation energy evolution in the case of Cr-Mo low-alloyed steel. All maps have been assembled on the basis of two flow curve datasets. The experimental one is the result of series of uniaxial hot compression tests. The predicted one has been calculated on the basis of the subsequent approximation procedure via a well-adapted artificial neural network. It was found that both flow stress and activation energy evolution are capable of expressing changes in the studied steel caused by the hot compression deformation. A direct association with the course of power dissipation efficiency is then evident in the case of both. The connection of the presence of instability districts to the activation energy evolution, flow stress course, and power dissipation efficiency was discussed further. Based on the obtained findings it can be stated that the activation energy processing maps represent another tool for the finding of appropriate forming conditions and can be utilized as a support feature for the conventionally-used processing maps to extend their informative ability.
在本研究中，利用叠加在流动应力图或激活能图上的传统热加工图，研究了Cr-Mo低合金钢在功率耗散效率、流动应力和激活能演变之间的相关性。所有的图都是基于两个流动曲线数据集组装而成的。实验数据集是一系列单轴热压缩试验的结果。预测数据集是通过一个适配良好的人工神经网络，基于后续的近似程序计算得出的。研究发现，流动应力和激活能演变都能够表达热压缩变形对所研究钢种造成的变化。在这两种情况下，与功率耗散效率的过程都存在直接关联。进一步讨论了不稳定区域的存在与激活能演变、流动应力过程和功率耗散效率之间的联系。基于所获得的研究结果，可以说激活能加工图是寻找合适成形条件的另一种工具，并且可以作为传统加工图的辅助特征来扩展其信息能力。
