Effects of Alloying Elements on Microstructure and Properties of Magnesium Alloys for Tripling Ball

et al. 2018

Materials & Corrosion

Corrosion property of AZ31‐xCu (x = 0, 0.5, 1.5, 3 wt%) alloys has been investigated using scanning electron microscope (SEM) equipped with energy dispersive spectroscope (EDS), X‐ray diffractometer (XRD), immersion tests, and electrochemical measurements. The results indicate that the content of AlCuMg phase, main secondary phase in the Cu‐containing alloys, is positively dependent on copper concentration. Acceleration of corrosion rate is found in Cu‐containing alloys due to micro‐galvanic corrosion. AlCuMg phase acts as micro‐galvanic cathode against anodic magnesium matrixes. In this regard, the degradation rate is decreasing in the following order: AZ31‐3Cu > AZ31‐1.5Cu > AZ31‐0.5Cu > AZ31.

P_{normalw} = 3.65 Δ W / ρ

where ΔW (mg cm −2 d −1 ) is the metallic weight loss rate; ρ is the density of samples and equals 1.74 g cm −3 for the studied magnesium alloys in the present study.…”

Section: Methodsmentioning

confidence: 99%

Accelerated degradation rate of AZ31 magnesium alloy by copper additions

Zhou

et al. 2018

Materials & Corrosion

“…Thus, to conquer these limitations, great efforts have been paid to improve the mechanical and degradable properties of the Mg alloys. So far, many degradable Mg-based materials with different components have recently been developed, such as Mg-1Ni-1.5Y, [10] Mg-3Zn-1Y-4Cu, [11] Dr. L. Liu Degradable materials with low density exhibit unique applications in the petroleum equipment field. Herein, hollow glass microspheres (HGM)-reinforced Mg alloy degradable composites are fabricated.…”

Section: Introductionmentioning

confidence: 99%

“…Thus, to conquer these limitations, great efforts have been paid to improve the mechanical and degradable properties of the Mg alloys. So far, many degradable Mg‐based materials with different components have recently been developed, such as Mg–1Ni–1.5Y, [ 10 ] Mg–3Zn–1Y–4Cu, [ 11 ] Mg–14Zn–Zr, [ 12 ] and Mg–17Al–7Cu–3Zn–1Gd [ 2 ] alloys. In these studies, to improve the comprehensive properties of Mg alloys, various alloying elements are added.…”

Section: Introductionmentioning

confidence: 99%

“…Previous investigations indicate that the Mg alloys with high Al and Zn contents exhibit simultaneously excellent compressive property and degradable property. [ 2,11 ] From the degradation behavior of view, the addition of Cu and Ni is favorable for the degradation of the Mg alloys because there is a large potential difference between Cu/Ni and Mg matrix, resulting in aggravation of galvanic corrosion. [ 10 ] Concurrently, studies have shown that the appropriate addition of Cu and Ni is expected to enhance the mechanical properties of Mg alloys.…”

Section: Introductionmentioning

confidence: 99%

“…[ 10 ] Concurrently, studies have shown that the appropriate addition of Cu and Ni is expected to enhance the mechanical properties of Mg alloys. [ 11,13 ] However, the addition of multiple alloying elements causes the increase in density of Mg alloys. It is mentioned that as downhole fracturing tools, the density of which should be as low as possible, so as to the degradation fragments could move with the flow of fracturing fluids.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Investigations on the Microstructure and Degradation Behavior of Hollow Glass Microspheres/Mg Alloy Composites

Lin

et al. 2021

Adv Eng Mater

Degradable materials with low density exhibit unique applications in the petroleum equipment field. Herein, hollow glass microspheres (HGM)‐reinforced Mg alloy degradable composites are fabricated. The microstructure and degradation behavior of the composites are investigated using scanning electron microscopy, immersion tests, and electrochemical measurements. Then the influence mechanisms of the HGM on the degradation property of composites are further revealed. The results show that the addition of the HGM significantly reduces the density of the composites. Different degrees of chemical reaction between the Mg alloy melt and HGM wall happen during the fabrication of the composites, resulting in the formation of MgO and Mg2Si. From the corrosive morphologies of the composites, Mg2Si phase can serve as a microgalvanic cathode consequently inducing more galvanic corrosion. The interface between HGM and matrix alloy can serve as the initiation site for pitting corrosion and increase the exposed area of the matrix in the aggressive medium. The electrochemical measurements prove that the HGM can act a part in facilitating the exfoliation of degradation products. Consequently, the HGM greatly increases the degradation rate of the composites in the KCl solution. The current study provides a new insight for developing lightweight Mg‐based composites with quickly degradable performance.

Enhanced Mechanical and Degradation Properties of Hollow Glass Microspheres/Mg Matrix Composites by Incorporating Copper Power for Degradable Downhole Tool Applications

et al. 2021

Adv Eng Mater

In this work, the effects of Cu addition on the microstructure, mechanical properties, and degradation behavior of the hollow glass microspheres/Mg alloy composites (HGM/MA) are investigated. The results indicate that with the Cu content increases from 0 to 2 wt.%, the grain size reduce from 17.89 AE 1.15 to 12.05 AE 0.85 μm, the compressive strength and Brinell hardness increase from 303 AE 5.5 MPa and 87.2 AE 2.5 HB to 381 AE 9.2 MPa and 119.8 AE 3.3 HB, increase by 25.7% and 37.4%, respectively. When the Cu content is less than 1 wt.%, the formed fine and dispersive Al 2 CuMg phase provides more galvanic-corrosion sites, and promotes the exfoliation of the corrosion product layer during degradation process, thereby accelerating the degradation rate. While the excessive Cu addition (>1.5 wt.%) results in the formation of net-like Al 2 CuMg phase, which can act as a corrosion barrier to hinder the further degradation of the composites. The composites with 3 wt.% Cu exhibits the highest degradation rate of 88.65 mg cm À2 h À1 in 3 wt.% KCl solution at 366 K, with a favorable ultimate compressive strength of 352 MPa, which is thought as an ideal candidate material for the degradable downhole tools.