SPD Processing Research Articles

Applications of Differential Scanning Calorimetry on Materials Subjected by Severe Plastic Deformation

Differential Scanning Calorimetry (DSC) is a thermal analysis technique that measures the energy absorbed or released by a sample as a function of temperature or time. DSC has wide application for analysis of solid state reactions and solid-liquid reactions in many different materials. In recent years, DSC has been applied to analyze materials and alloys processed through Severe Plastic Deformation (SPD). The basic principle of SPD processing is that a very high strain is introduced into materials which achieve significant grain refinement and improve properties of materials. This review paper presents some recent examples of the applications of DSC for materials subjected to SPD, especially by Equal-Channel Angular Pressing and High-Pressure Torsion.

Recent Developments of Severe Plastic Deformation Techniques for Processing Bulk Nanostructured Materials

Since the mid-1990’s the fabrication of bulk nanostructured metals and alloys using severe plastic deformation (SPD) has been evolving as a rapidly advancing direction of modern nano-materials science that is aimed at developing materials with new mechanical and functional properties for advanced applications. This paper highlights and considers two new trends in SPD processing, which are recently being developed for fabrication of bulk nanostructured materials (BNM). One of these recent developments is associated with nanostructuring of metals and alloys by SPD processing for advanced properties. The new strategies and approaches to produce nanometals with enhanced and often unique properties are discussed. Another new direction is the progress in the processing of BNM not only at laboratory scale but also at the level semi-products (sheets, wires, rods, etc.) suitable for production implementation. The paper considers these developments together with the examples performed at our laboratory in Ufa (Russia), which lay a firm foundation for the BNM use in advanced structural and functional applications.

Effect of Equal Channel Angular Pressing and Repeated Rolling on Structure, Phase Transformations and Properties of TiNi Shape Memory Alloys

The nanostructured TiNi-based shape-memory alloys were synthesized by multi-step SPD deformations – ECAP plus cold rolling or drawing. It is found that the SPD processing changed the morphology of the martensite and temperature of martensite transformation. Also, we found that the mechanical and shape memory properties can be enhanced by forming nanostructures in these alloys. SPD processing renders higher strength, higher yield dislocation strength and in results - higher recovery stress and maximum reverse strain of shape memory.

On the effect of SPD on recycled experimental aluminium alloys: Nanostructures, particle break-up and properties

As a part of on-going research on the effects of recycled alloy chemistries on alloy design, properties and applications, the present work focuses on SPD processing. ECAP is used to deform two different Al alloys with “recycled alloy chemistry” and a standard AlMgSi alloy. A comparison between deformation routes A and B C is performed to evaluate the effects of deformation path on particle break-up and particle distributions. Both alloy content, amount of accumulated strain and choice of deformation route influenced particle refinement.

Recent Developments of SPD Processing for Fabrication of Bulk Nanostructured Materials

Recent Developments of SPD Processing for Fabrication of Bulk Nanostructured Materials

Developing of SPD processing and enhanced properties in bulk nanostructured metals

Developing of SPD processing and enhanced properties in bulk nanostructured metals

SPD Processing and Properties of Metastable Nanostructured Alloys

SPD Processing and Properties of Metastable Nanostructured Alloys

SPD Processing and Properties of Metastable Nanostructured Alloys

SPD Processing and Properties of Metastable Nanostructured Alloys

SPD Processing and Superplasticity in Ultrafine-Grained Alloys

AbstractSevere plastic deformation (SPD), for example by intense plastic straining under high pressure, is an innovative technique for producing ultrafine-grained (UFG) metals and alloys. The SPD fabricated UFG structures can lead to enhanced superplasticity, which, however, depends strongly on processing parameters. The present paper focuses on examples of attaining enhanced superplasticity in several alloys, subjected to SPD and considers the relationship between processing – UFG structures – superplastic properties in SPD produced materials.

The influence of surface on the rusting of iron

Combining transmission Kikuchi diffraction, high resolution transmission electron microscopy and atom probe tomography, we investigated an Al-Zn-Mg-Cu alloy (AA7075) processed by high-pressure torsion (HPT) at room temperature and 200 °C, with an objective to reveal the deformation-induced precipitation and segregation of elements at grain boundaries, and to study their appearance at different processing regimes. Although HPT processing at the two temperatures both induced the formation of ŋ phase, ŋ precipitates formed at the two temperatures have different chemical compositions. The increase of the HPT processing temperature increased significantly segregation of Mg and Cu at grain boundaries. The HPT–induced segregation and decomposition of the alloy have a significant effect on its mechanical strength. Our results open a way for achieving advanced mechanical properties in nanostructured metals and alloys by designing their precipitation and segregation through the control of SPD processing regimes.