Effect of Equal Channel Angular Pressing (ECAP) on Erosion-Corrosion of Pure Copper

Abstract

Abstract:During the past few decades, ultrafine-grained materials (UFG) have experienced rapid development. Enhanced mechanical and surface properties, such as strength, ductility and erosioncorrosion (E-C) resistance by refining the grain to ultra-fine/nanometer size has been achieved. The equal channel angular pressing (ECAP) is a popular severe plastic deformation (SPD) method to fabricate UFG bulk materials. In this research, the E-C behavior of commercial annealed pure copper subject to four passes of ECAP have been investigated. Hardness measurement of the copper specimen after four passes of ECAP showed an increase of 200% on the hardness value as compared with annealed condition. Simulated seawater was used as an E-C medium. The effect of different E-C parameters such as time, slurry flow velocity, impact angle, and solid particle concentration on ECAP process is studied. The results showed that ECAP enhances the E-C resistance of copper, and this behavior improves with increasing the pass number. Generally, a 30% rise in resistance to E-C was achieved after four ECAP passes as compared to coarse grain copper for the parameters studied in this work. Optical microscopy was used to examine the microstructure and material removal mechanism of the annealed copper. Scanning electron microscopy (SEM) was used to validate the reduction of grain size due to ECAP process. Furthermore, examination of the surface roughness of the copper at different ECAP passes showed that for the same E-C condition the increment of ECAP passes leads to a smoother surface.

Erosion Corrosion Behavior of Nanostructure Commercial Pure Titanium in Simulated Body Fluid

“…Here, it is also true that uneven distribution of strain which is result of induced stress can accelerates the corrosion rate, hence specimens with highest homogeneity are most resistance to the corrosion. Similar trend was observed when studying the effect of time on erosion corrosion of ECAPed copper [12][13].…”

“…However, under E -C conditions, the surface passive film might be damaged or even removed by which it may lead in an increased corrosion rate [1]. There are limited studies on the E-C behavior of UFG/NSG materials [12,13]. Therefore, the current work addresses this issue, and compares the E-C resistance of commercial pure titanium CP-Ti with ultrafine/nanostructured grain (UFG/NSG) Titanium fabricated by ECAP as sever plastic deformation process in a simulated body fluid.…”

Surface Roughness Investigation and Stress Modeling by Finite Element on Orthogonal Cutting of Copper

“…The roughness was also assessed in terms of Ra, Rp, Rq, Rt, and Rv parameters to evaluate the surface quality after orthogonal cutting by turning operation [41]. The variations of roughness parameters as a function of the cutting speed at constant feed rate and depth of cut are displayed in Figure 9.…”

A New Method of Predicting the Structural and Mechanical Change of Materials during Extrusion by the Method of Multiple Plastic Deformations

“…Nanostructured pure copper seems to be a very interesting material in many areas, mainly in electronics. Experimental research described in the paper by Irfan et al [ 30 ] was carried out to investigate the influence of ECAP on erosion-corrosion of pure copper. The most important parameter affecting the behavior of copper after ECAP was the impacting angle and velocity.…”