The possibility to study and clearly define the physics phenomena that occur during the machining process of various metal materials is becoming one of the interpretative keys to quantify a product’s quality and life cycle performance. An accurate understanding of the surface integrity can be achieved through the knowledge of the fundamental details about the mechanical response and the behaviour of the affected material layers caused by thermo-mechanical loads induced by machining operations. Therefore, this set of information can help the designer to produce parts with superior quality. The aim of this work is to study the surface layer states in terms of metallurgical and mechanical properties of aluminium alloy 7075 in a machined and a sereverely plastic deformed by the Equal Channel Angular Pressing (ECAP) process. The outcomes provided by the experimental measurements permitted to find possible links regarding the microstructural and hardness changes observed between the machined surface layer and the region of material deformed by ECAP. Finally, this scientific investigation aims to establish the basis for an innovative method to study and quantify the metallurgical phenomena that occur beneath the machined surface of bulk metal materials.

研究并清楚地定义各种金属材料的加工过程中发生的物理现象的可能性正成为量化产品质量和生命周期性能的解释性关键之一。通过了解有关机械响应和由加工操作引起的热机械载荷引起的受影响材料层的行为的基本细节，可以对表面完整性有一个准确的了解。因此，这套信息可以帮助设计人员生产出质量更高的零件。这项工作的目的是研究通过等通道角挤压（ECAP）工艺在经过机械加工和剧烈塑性变形的铝合金7075的冶金和机械性能方面的表层状态。实验测量提供的结果允许找到关于在机械加工的表面层和被ECAP变形的材料区域之间观察到的微观结构和硬度变化的可能联系。最后，这项科学研究旨在为研究和量化散装金属材料加工表面下发生的冶金现象的创新方法奠定基础。