Corrosion behavior of ZnO-polyester nanocomposite powder coating

2017 ◽  
Vol 64 (4) ◽  
pp. 380-388 ◽  
Author(s):  
Aboozar Golgoon ◽  
Mahmood Aliofkhazraei ◽  
Mansoor Toorani ◽  
Mohammad Hossein Moradi ◽  
Alireza Sabour Rouhaghdam ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Zno Nanoparticles ◽  
Barrier Properties ◽  
Powder Coating ◽  
Nanocomposite Coating ◽  
Milling Process ◽  
Content Type ◽  
The Matrix ◽  
Agglomeration Of Nanoparticles ◽  
Partial Covering

Purpose The low resistance against penetration of water, oxygen and the other corrosive ions through the paths of coating is one the most important problems. So, protective properties of coating such as polyester must be promoted. Recently, the use of nanoparticles in the matrix of polymer coating to increase their protection and mechanical properties has been prospering greatly. The purpose of this study is to improve the corrosion resistance of the polyester powder coating with ZnO nanoparticles. The ZnO nanoparticles have been synthesized by hydrothermal method in a microwave. Using polyester – ZnO nanocomposite coating as powder – combining them by ball milling process and coating them by electrostatic process are innovative ideas and have not been used before it. Design/methodology/approach Polyester powder as the matrix and ZnO nanoparticles as reinforcing were combined in three different weight percentage (0.5, 1, 2 Wt.%), and they formed polymer nanocomposite by ball milling process. Then, the fabricated nanocomposite powder was applied to the surface of carbon steel using an electrostatic device, and then the coatings were cured in the furnace. The morphology of synthesized zinc oxide nanoparticles was investigated by transmission electron microscope. Also, the morphology of polyester powder and fabricated coatings was studied by scanning electron microscope. The effects of zinc oxide nanoparticles on the corrosion resistance of coated samples were studied by electrochemical impedance spectroscopy (EIS) test at various times (1-90 days) of immersion in 3.5 per cent NaCl electrolyte. Findings Scanning electron microscopy (SEM) results reveal that there are no obvious crack and defects in the nanocomposite coatings. In contrast, the pure polyester coatings having many cracks and pores in their structure. According to the EIS results, the corrosion resistance of nanocomposite coating compared to pure coating is higher. The value obtained from EIS test show that corrosion resistance for coating that contains 1 Wt.% nanoparticle was 32,150,000 (Ωcm2), which was six times bigger than that of pure coating. In addition to providing a barrier against diffusion of electrolyte, ZnO nanoparticles act as a corrosion inhibitor and, thus, increases the corrosion resistance. The corrosion resistance of coating containing 0.5 Wt.% nanoparticles was lower as compared to that of 1 Wt.% nanoparticles. The low content of nanoparticles caused partial covering of the porosity of coating which in turn leads to provide weaker barrier properties. The increase in quantity of nanoparticles from 1 to 2 Wt.% also caused a decrease in corrosion resistance which is attributed to the agglomeration of nanoparticles. Originality/value The results of this study indicated the significant effect of ZnO nanoparticles on the protective performance and corrosion resistance of the polyester powder coating. Evaluation of coating surface and interface with SEM technique revealed that nanocomposite coating compared with pure polyester coating provided a coating with lower number of pores and with higher quality. The EIS measurements represented that polymeric coating that contains nanoparticles compared to pure coating provides a better corrosion resistance. In addition to providing a barrier against diffusion of electrolyte, ZnO nanoparticles act as a corrosion inhibitor and thus increase the corrosion resistance. The corrosion resistance of coating containing 0.5 Wt.% nanoparticles was lower as compared to that containing 1Wt.% nanoparticles. The low content of nanoparticles caused partial covering of the porosity of coating which in turn leads to provide weaker barrier properties. The increase in quantity of nanoparticles from 1 to 2 Wt.% also caused a decrease in corrosion resistance which is attributed to the agglomeration of nanoparticles.

Effect of urea–formaldehyde nanoparticles on the barrier property and delamination resistance for epoxy coating

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Zhe Li ◽  
Hongpeng Zheng ◽  
Li Liu ◽  
Fandi Meng ◽  
Yu Cui ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Composite Coating ◽  
Urea Formaldehyde ◽  
Sol Gel ◽  
Milling Process ◽  
Barrier Property ◽  
Metal Interface ◽  
Content Type ◽  
Uf Resin ◽  
Delamination Resistance

Purpose The purpose of this paper is to investigate the effect of urea–formaldehyde (UF) nanoparticles on the barrier property and delamination resistance for epoxy coating in a 3.5% NaCl aqueous solution. Design/methodology/approach The UF resin was synthesized via sol–gel method, and UF/epoxy composite coating was prepared through ball-milling process; the microstructure and chemical composition of UF resin were observed using the Fourier transform infrared spectroscopy, scanning electron microscopy and transmission electron microscopy; the bonding strength of coating/metal interface was investigated through adhesion test; the mechanical properties of the coatings were studied by tensile tests; and the barrier and corrosion resistance properties were verified using salt spray test, cathodic delamination test and electrochemical impedance spectroscopy measurements. Findings The experimental results indicated that the UF resin presented uniformly dispersed nanoparticles in the epoxy matrix and enhanced the bonding strength of coating/metal interface and then improved the delamination resistance for composite coating, which resulted in the enhancement of the barrier property and corrosion resistance for UF/epoxy composite coating. Originality/value In this paper, an easily prepared blending compounding coating with excellent corrosion resistance property was synthesized via sol–gel method and ball-milling process. The effects of UF nanoparticles on the barrier property and delamination resistance were investigated in detail.

Corrosion inhibition properties of SiO2-ZrO2 nanocomposite coating on carbon steel 178

2018 ◽  
Vol 65 (1) ◽  
pp. 66-72 ◽  
Author(s):  
Behnam Abdollahi ◽  
Daryoush Afzali ◽  
Zahra Hassani
Keyword(s):  
Corrosion Resistance ◽  
Carbon Steel ◽  
Corrosion Behavior ◽  
Electrochemical Impedance ◽  
Sol Gel ◽  
Nanocomposite Coating ◽  
Coating Film ◽  
Nacl Solution ◽  
Electrochemical Polarization ◽  
Content Type

Purpose SiO2 and SiO2-ZrO2 nanocomposites were coated by sol–gel dipping method on carbon steel 178 (178 CS). Nanostructure and phase properties of nanocomposite coating were characterized using X-ray diffraction, scanning electron microscopy and Fourier transform infrared studies. Electrochemical polarization and electrochemical impedance spectroscopy (EIS) tests were used to study the corrosion behavior of 178 CS that was coated with SiO2-ZrO2 nanocomposite and SiO2 coating in 3.5 per cent NaCl solution. The results indicated that SiO2-ZrO2 nanocomposite coating performed better in terms of corrosion resistance compared with SiO2 coating. The corrosion resistance of SiO2-ZrO2 nanocomposite coating could be increased significantly in by approximately three and seven times of that of SiO2 coating and bare 178 CS, respectively. Design/methodology/approach SiO2 and SiO2-ZrO2 nanocomposites were coated using sol–gel dipping method on carbon steel 178. Electrochemical polarization and EIS tests have been used to study the corrosion behavior of 178 CS that was coated with SiO2-ZrO2 nanocomposite and SiO2 coating in 3.5 per cent NaCl solution. Findings Results indicated that SiO2-ZrO2 nanocomposite coating performed better in terms of corrosion resistance compared with SiO2 coating. The corrosion resistance of SiO2-ZrO2 nanocomposite coating could be increased significantly in by approximately three and seven times of that of SiO2 coating and bare 178 CS, respectively. Originality/value The SiO2-ZrO2 nanocomposite coating film showed significant improvement in corrosion resistance of 178 CS. The highest polarization resistance of the nanocomposite coating film was 10,600 Ω/cm2 from SiO2-0.2 ZrO2.

COLMONOY 805

Alloy Digest ◽  
1998 ◽  
Vol 47 (12) ◽  
Keyword(s):  
Corrosion Resistance ◽  
Physical Properties ◽  
Abrasion Resistance ◽  
Coarse Particles ◽  
Powder Metal ◽  
Chromium Boride ◽  
Nickel Chromium ◽  
The Matrix

Abstract Colmonoy 805 is a nickel-chromium-boron alloy with coarse particles of chromium boride added to give it excellent sliding-type abrasion resistance. The alloy contains chromium boride in the matrix as large added particles. It is supplied only as a crushed powder for application with Colmonoy’s Fuseweld process. This datasheet provides information on composition, physical properties, microstructure, and elasticity. It also includes information on corrosion resistance as well as joining and powder metal forms.Filing Code: Ni-233. Producer or source: Wall Colmonoy Corporation. Originally published September 1976, revised December 1998.

Study on high-temperature wear and mechanism of Al-Si/graphite composites prepared by the die-casting process

2020 ◽  
Vol 72 (10) ◽  
pp. 1153-1158 ◽  
Author(s):  
Yafei Deng ◽  
Xiaotao Pan ◽  
Guoxun Zeng ◽  
Jie Liu ◽  
Sinong Xiao ◽  
...  
Keyword(s):  
Friction Coefficient ◽  
Wear Rate ◽  
Peer Review ◽  
Die Casting ◽  
Casting Machine ◽  
Injection Pressure ◽  
Casting Process ◽  
Matrix Alloy ◽  
Content Type ◽  
The Matrix

Purpose This paper aims to improve the tribological properties of aluminum alloys and reduce their wear rate. Design/methodology/approach Carbon is placed in the model at room temperature, pour 680°C of molten aluminum into the pressure chamber, and then pressed it into the mold containing carbon felt through a die casting machine, and waited for it to cool, which used an injection pressure of 52.8 MPa and held the same pressure for 15 s. Findings The result indicated that the mechanical properties of matrix and composite are similar, and the compressive strength of the composite is only 95% of the matrix alloy. However, the composite showed a low friction coefficient, the friction coefficient of Gr/Al composite is only 0.15, which just is two-third than that of the matrix alloy. Similarly, the wear rate of the composite is less than 4% of the matrix. In addition, the composite can avoid severe wear before 200°C, but the matrix alloy only 100°C. Originality/value This material has excellent friction properties and is able to maintain this excellent performance at high temperatures. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-10-2019-0454/

scholarly journals Effect of Vanadium Reinforcement on the Microstructure and Mechanical Properties of Magnesium Matrix Composites

Crystals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 806
Author(s):  
Liqing Sun ◽  
Shuai Sun ◽  
Haiping Zhou ◽  
Hongbin Zhang ◽  
Gang Wang ◽  
...  
Keyword(s):  
Grain Size ◽  
Grain Refinement ◽  
Milling Process ◽  
Mg Alloy ◽  
Matrix Composites ◽  
Magnesium Matrix Composites ◽  
Pinning Effect ◽  
Average Grain Size ◽  
The Matrix ◽  
Hot Press Sintering

In this work, vanadium particles (VP) were utilized as a novel reinforcement of AZ31 magnesium (Mg) alloy. The nanocrystalline (NC) AZ31–VP composites were prepared via mechanical milling (MM) and vacuum hot-press sintering. During the milling process, the presence of VP contributed to the cold welding and fracture mechanism, resulting in the acceleration of the milling process. Additionally, increasing the VP content accelerated the grain refinement of the matrix during the milling process. After milling for 90 h, the average grain size of AZ31-X wt % Vp (X = 5, 7.5, 10) was refined to only about 23 nm, 19 nm and 16 nm, respectively. In the meantime, VP was refined to sub-micron scale and distributed uniformly in the matrix, exhibiting excellent interfacial bonding with the matrix. After the sintering process, the average grain size of AZ31-X wt % VP (X = 5, 7.5, 10) composites still remained at the NC scale, which was mainly caused by the pinning effect of VP. Besides that, the porosity of the sintered composites was no more than 7.8%, indicating a good densification effect. As a result, there was little difference between the theoretical and real density. Compared to as-cast AZ31 Mg alloy, the microhardness of sintered AZ31-X wt % VP (X = 5, 7.5, 10) composites increased by 65%, 87% and 96%, respectively, owing to the strengthening mechanisms of grain refinement strengthening, Orowan strengthening and load-bearing effects.

scholarly journals Comparison of Structure and Properties of Mo2FeB2-Based Cermets Prepared by Welding Metallurgy and Vacuum Sintering

Materials ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 46
Author(s):  
Hu Xu ◽  
Junsheng Sun ◽  
Jun Jin ◽  
Jijun Song ◽  
Chi Wang
Keyword(s):  
Wear Resistance ◽  
Corrosion Resistance ◽  
Volume Fraction ◽  
Phase Evolution ◽  
304 Stainless Steel ◽  
Vacuum Sintering ◽  
Cored Wire ◽  
Welding Metallurgy ◽  
Metallurgical Bonding ◽  
The Matrix

At present, most Mo2FeB2-based cermets are prepared by vacuum sintering. However, vacuum sintering is only suitable for ordinary cylinder and cuboid workpieces, and it is difficult to apply to large curved surface and large size workpieces. Therefore, in order to improve the flexibility of preparing Mo2FeB2 cermet, a flux cored wire with 70% filling rate, 304 stainless steel, 60 wt% Mo powder and 40 wt% FeB powder was prepared. Mo2FeB2 cermet was prepared by an arc cladding welding metallurgy method with flux cored wire. In this paper, the microstructure, phase evolution, hardness, wear resistance and corrosion resistance of Mo2FeB2 cermets prepared by the vacuum sintering (VM-Mo2FeB2) and arc cladding welding metallurgy method (WM-Mo2FeB2) were systematically studied. The results show that VM-Mo2FeB2 is composed of Mo2FeB2 and γ-CrFeNi.WM-Mo2FeB2 is composed of Mo2FeB2, NiCrFe, MoCrFe and Cr2B3. The volume fraction of hard phase in WM-Mo2FeB2 is lower than that of VM-Mo2FeB2, and its hardness and corrosion resistance are also slightly lower than that of VM-Mo2FeB2, but there are obvious pores in the microstructure of VM-Mo2FeB2, which affects its properties. The results show that WM-Mo2FeB2 has good diffusion and metallurgical bonding with the matrix and has no obvious pores. The microstructure is compact and the wear resistance is better than that of VM-Mo2FeB2.

scholarly journals Nanocomposites Materials of PLA Reinforced with Nanoclays Using a Masterbatch Technology: A Study of the Mechanical Performance and Its Sustainability

Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2133
Author(s):  
Helena Oliver-Ortega ◽  
Josep Tresserras ◽  
Fernando Julian ◽  
Manel Alcalà ◽  
Alba Bala ◽  
...  
Keyword(s):  
Food Packaging ◽  
Mechanical Performance ◽  
Polymeric Materials ◽  
Barrier Properties ◽  
Food Tray ◽  
Environmental Concerns ◽  
Poly Lactic Acid ◽  
The Matrix ◽  
Surface Modified ◽  
Being Moved

Packaging consumes around 40% of the total plastic production. One of the most important fields with high requirements is food packaging. Food packaging products have been commonly produced with petrol polymers, but due to environmental concerns, the market is being moved to biopolymers. Poly (lactic acid) (PLA) is the most promising biopolymer, as it is bio-based and biodegradable, and it is well established in the market. Nonetheless, its barrier properties need to be enhanced to be competitive with other polymers such as polyethylene terephthalate (PET). Nanoclays improve the barrier properties of polymeric materials if correct dispersion and exfoliation are obtained. Thus, it marks a milestone to obtain an appropriate dispersion. A predispersed methodology is proposed as a compounding process to improve the dispersion of these composites instead of common melt procedures. Afterwards, the effect of the polarity of the matrix was analyzing using polar and surface modified nanoclays with contents ranging from 2 to 8% w/w. The results showed the suitability of the predispersed and concentrated compound, technically named masterbatch, to obtain intercalated structures and the higher dispersion of polar nanoclays. Finally, the mechanical performance and sustainability of the prepared materials were simulated in a food tray, showing the best assessment of these materials and their lower fingerprint.

Fatigue behavior of precipitation strengthened Cu–Ni–Si alloy modified by Cr and Zr addition

2020 ◽  
Vol 11 (6) ◽  
pp. 861-873
Author(s):  
Ş. Hakan Atapek ◽  
Spiros Pantelakis ◽  
Şeyda Polat ◽  
Apostolos Chamos ◽  
Gülşah Aktaş Çelik
Keyword(s):  
Design Methodology ◽  
Fatigue Behavior ◽  
Fatigue Tests ◽  
Lower Stress ◽  
Content Type ◽  
Hardened Alloy ◽  
Zr Addition ◽  
Nucleation Sites ◽  
The Matrix ◽  
Lower Stress Level

Purpose The purpose of this paper is to investigate the fatigue behavior of precipitation-strengthened Cu‒2.55Ni‒0.55Si alloy, modified by the addition of 0.25 Cr and 0.25 Zr (wt%), using mechanical and fractographical studies to reveal the effect of microstructural features on the fracture. Design/methodology/approach For strengthening, cast and hot forged alloy was subjected to solution annealing at 900°C for 60 min, followed by quenching in water and then aging at 490°C for 180 min. Precipitation-hardened alloy was exposed to fatigue tests at R=−1 and different stress levels. All fracture surfaces were examined within the frame of fractographical analysis. Findings Fine Ni-rich silicides responsible for the precipitation strengthening were observed within the matrix and their interactions with the dislocations at lower stress level resulted in localized shearing and fine striations. Although, by the addition of Cr and Zr, the matrix consisted of hard Ni, Zr-rich and Cr-rich silicides, these precipitates adversely affected the fatigue behavior acting as nucleation sites for cracks. Originality/value These findings contribute to the present knowledge by revealing the effect of microstructural features on the mechanical behavior of precipitation-hardened Cu‒Ni‒Si alloy modified by Cr and Zr addition.

A study on tribological behaviour and analysis of ZnO reinforced AA6061 matrix composites fabricated by stir casting route

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Sakthi Sadhasivam RM ◽  
Ramanathan K. ◽  
Bhuvaneswari B.V. ◽  
Raja R.
Keyword(s):  
Wear Rate ◽  
Sliding Wear ◽  
Stir Casting ◽  
Industrial Applications ◽  
Wear Behaviour ◽  
Matrix Composites ◽  
Tribological Behaviour ◽  
Content Type ◽  
Zno Particles ◽  
The Matrix

Purpose The most promising replacements for the industrial applications are particle reinforced metal matrix composites because of their good and combined mechanical properties. Currently, the need of matrix materials for industrial applications is widely satisfied by aluminium alloys. The purpose of this paper is to evaluate the tribological behaviour of the zinc oxide (ZnO) particles reinforced AA6061 composites prepared by stir casting route. Design/methodology/approach In this study, AA6061 aluminium alloy matrix reinforced with varying weight percentages (3%, 4.5% and 6%) of ZnO particles, including monolithic AA6061 alloy samples, is cast by the most economical fabrication method, called stir casting. The prepared sample was subjected to X-ray photoelectron spectroscopy (XPS) analysis, experimental density measurement by Archimedian principle and theoretical density by rule of mixture and hardness test to investigate mechanical property. The dry sliding wear behaviour of the composites was investigated using pin-on-disc tribometer with various applied loads of 15 and 20 N, with constant sliding velocity and distance. The wear rate, coefficient of friction (COF) and worn surfaces of the composite specimens and their effects were also investigated in this work. Findings XPS results confirm the homogeneous distribution of ZnO microparticles in the Al matrix. The Vickers hardness result reveals that higher ZnO reinforced (6%) sample have 34.4% higher values of HV than the monolithic aluminium sample. The sliding wear tests similarly show that increasing the weight percentage of ZnO particles leads to a reduced wear rate and COF of 30.01% and 26.32% lower than unreinforced alloy for 15 N and 36.35% and 25% for 20 N applied load. From the worn surface morphological studies, it was evidently noticed that ZnO particles dispersed throughout the matrix and it had strong bonding between the reinforcement and the matrix, which significantly reduced the plastic deformation of the surfaces. Originality/value The uniqueness of this work is to use the reinforcement of ZnO particles with AA6061 matrix and preparing by stir casting route and to study and analyse the physical, hardness and tribological behaviour of the composite materials.

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