Maril Yasmin, Camurri Carlos, Zapata-Hernández Oscar, Carrasco Claudia, Maril Marisol
Department of Materials Engineering, University of Concepción, Edmundo Larenas 315, Concepción 4070415, Chile.
FIME-Centro de Investigación e Innovacion en Ingenieria Aeronautica (CIIIA), Universidad Autonoma de Nuevo Leon, Av. Universidad S/N, Ciudad Universitaria, San Nicolás de los Garza 66455, Mexico.
Materials (Basel). 2023 Sep 26;16(19):6416. doi: 10.3390/ma16196416.
This study presents a novel approach to producing superficial micro- and nanostructures using a cold rolling process with rough rolls, followed by low-temperature annealing. The proposed technique attempts to recreate the superficial deformation occurring in the sandblasting process. It allows for the generation of an inhomogeneous network, or tangle, of high-deformation zones on the material's surface that act as nucleation centers during the subsequent annealing process. However, the proposed method has a significant advantage over sandblasting: it is a continuous process with high productivity. An austenitic stainless-steel sheet, previously normalized, was used as the raw material. The samples were cold rolled using rough rolls (rhombic-based pyramids of 2.08 mm, 1.04 mm, and 1.5 mm in length, width, and height, respectively) and annealed at temperatures between 200 °C and 400 °C for one hour. An optical and electronic microstructure analysis showed the presence of small, heterogeneously distributed surface grains of 200-300 nm in diameter. Finite element analysis revealed significant deformation that was inhomogeneous and likely responsible for the uneven distribution of the recrystallized grains. Additionally, surface nanohardness results showed a 20% increase with respect to the central zone of the material. Finally, wear tests of the treated samples showed lower wear than samples rolled with conventional rolls.
本研究提出了一种新颖的方法，通过使用带有粗糙轧辊的冷轧工艺，随后进行低温退火来制造表面微观和纳米结构。所提出的技术试图重现喷砂过程中发生的表面变形。它能够在材料表面生成不均匀的网络或缠结的高变形区域，这些区域在随后的退火过程中充当形核中心。然而，所提出的方法相对于喷砂具有显著优势：它是一个具有高生产率的连续过程。使用预先正火的奥氏体不锈钢板作为原材料。样品使用粗糙轧辊（长度、宽度和高度分别为2.08毫米、1.04毫米和1.5毫米的菱形金字塔）进行冷轧，并在200℃至400℃之间的温度下退火一小时。光学和电子微观结构分析表明存在直径为200 - 300纳米的小的、不均匀分布的表面晶粒。有限元分析显示出显著的不均匀变形，这可能是再结晶晶粒分布不均匀的原因。此外，表面纳米硬度结果表明相对于材料的中心区域增加了20%。最后，对处理后的样品进行的磨损测试表明，其磨损低于用传统轧辊轧制的样品。
