Material Recovery of OFHC Cu and FeSi Steel after Processing by Plastic Deformations

Abstract

The influence of thermoplastic processes through severe plastic deformations carried out at ambient temperature and through rolling carried out at cryogenic temperature on the recovery for two types of materials was investigated. As experimental materials, there were used oxygen free high conductivity copper and FeSi steel presenting materials with middle and high stacking fault energy, respectively. Both materials have been previously investigated, however mainly considering their material properties. In this study, oxygen free high conductivity Cu was processed by 13 passes through equal channel angular rolling which belongs to the severe plastic deformations group of methods. The rolling of FeSi steel at ambient and cryogenic temperatures was performed using a laboratory duo rolling mill, samples were rolled only by one pass. The aim of this study was to insert the strain to the materials with different stacking fault energy (middle and high) under ambient and cryogenic thermal conditions, respectively, and subsequently to observe the influence of stored energy on structural recovery of materials through differential scanning calorimetry method. This study implies that the recovery process characterized by the mobility of structural defects begins earlier for FeSi steel compared to oxygen free high conductivity Cu.

Theoretical-Experimental Possibillities of Microstructure Quantification of Dispersion Strengthened Materials

“…The research proceeds in several directions the most important of which are new metallic alloys, ceramics, polymers, composites and amorphous materials. The composite materials with metallic, plastic and ceramic bases have already found their application in the machine industry, but their wider use is still limited by insufficient automation on their production resulting in their cost and by the need to elaborate new designs and techniques adapted for a better understanding and influencing of their properties, [1][2][3][4][5][6][7][8]. The mechanism of dispersion strengthening is based on the presence of a low volume fraction of fine secondary particles in the metal matrix, [9 -11].…”