Petryshynets Ivan, Kováč František, Petrov Branislav, Falat Ladislav, Puchý Viktor
Institute of Materials Research, Slovak Academy of Sciences, Watsonova 47, 04001 Košice, Slovakia.
Faculty of Materials, Metallurgy and Recycling, Technical University of Košice, Letná 9, 04200 Košice, Slovakia.
Materials (Basel). 2019 Jun 13;12(12):1914. doi: 10.3390/ma12121914.
In the present work, we have used unconventional short-term secondary recrystallization heat treatment employing extraordinary high heating rate to develop coarse-grained microstructure with enhanced intensity of rotating cube texture {100}<011> in semi-finish vacuum degassed non-oriented electrical steels. The soft magnetic properties were improved through the increase of grains size with favourable cube crystallographic orientation. The appropriate final textural state of the treated experimental steels was achieved by strain-induced grain boundary migration mechanism, activated by gradient of accumulated stored deformation energy between neighbouring grains after the application of soft cold work, combined with steep temperature gradient during subsequent heat treatment under dynamic heating conditions. The materials in our experimentally prepared material states were mounted on the stator and rotor segments of electrical motors and examined for their efficiency in real operational conditions. Moreover, conventionally long-term heat treated materials, prepared in industrial conditions, were also tested for reference. The results show that the electrical motor containing the segments treated by our innovative approach, exhibits more than 1.2% higher efficiency, compared to the motor containing conventionally heat treated materials. The obtained efficiency enhancement can be directly related to the improved microstructural and textural characteristics of our unconventionally heat treated materials, specifically the homogenous coarse grained microstructure and the high intensity of cube and Goss crystallographic texture.
在本工作中，我们采用了非常规的短期二次再结晶热处理，采用极高的加热速率，以在半终轧真空脱气无取向电工钢中形成具有增强的旋转立方织构{100}<011>强度的粗晶组织。通过增加具有有利立方晶体取向的晶粒尺寸，改善了软磁性能。经过处理的实验钢合适的最终织构状态是通过应变诱导晶界迁移机制实现的，该机制在施加软冷轧后由相邻晶粒间累积储存变形能的梯度激活，并在动态加热条件下后续热处理期间结合陡峭的温度梯度。我们实验制备的材料状态下的材料被安装在电动机的定子和转子段上，并在实际运行条件下检测其效率。此外，还测试了在工业条件下制备的传统长期热处理材料作为参考。结果表明，与包含传统热处理材料的电动机相比，包含采用我们创新方法处理的段的电动机效率高出1.2%以上。所获得的效率提高可直接归因于我们非常规热处理材料改善的微观结构和织构特性，特别是均匀的粗晶组织以及立方和高斯晶体织构的高强度。
