Wyniki wyszukiwania - BazTech

1

Effect of Fe and Mn on corrosion resistance of recycled self-hardening AlZn10Si8Mg alloy

Mikolajčík Martin, Tillová Eva, Kuchariková Lenka, Šurdová Zuzana

Production Engineering Archives

|

2025

|

Vol. 31, Iss. 1

54--64

EN

Recycled aluminium alloys are a highly valued alternative for manufacturers, particularly in the automotive and aerospace industries, due to increasing demands on the environmental performance and sustainability of the industry. Self-hardening aluminium alloys, which achieve the required mechanical properties without heat treatment, enable the emissions generated by production to be reduced even further. In addition to an advantageous strength-to-weight ratio and excellent machinability, corrosion resistance in a variety of environments is also important in most applications of aluminium alloys. Repeated recycling cycles negatively influence the quality of aluminium because of an increase in iron content, which is considered an impurity. This is due to the formation of intermetallic phases which negatively affect the mechanical, fatigue and corrosion properties. In this paper, the effect of Fe and Mn on the microstructure and corrosion resistance of self-hardening recycled AlZn10Si8Mg alloy was investigated using the AUDI test, atmospheric long-terming test and 3.5% NaCl solution test. The corrosion mechanism was subsequently determined by sectioning the samples. Alloy A with the lowest iron content exhibited the best corrosion behaviour, as it was subjected to only localised forms of corrosion even in the aggressive environment of the AUDI test. In this environment, the other alloys were attacked by general corrosion of the entire surface. Manganese alloying caused a subtle improvement in the corrosion resistance of alloy D but was limited by the high porosity. The eutectic and intermetallic phases corroded the most, while the alpha phase was more resistant.

2

Three-layer Repair Coating System for Manholes, Pump Stations, and Tanks in Aggressive Sulfate Environment

Pawlak Tomasz, Szymczak-Graczyk Anna, Garbowski Tomasz

Civil and Environmental Engineering Reports

|

2025

|

Vol. 35, no. 1

1--19

EN

Advancements in the repair and protection of water and wastewater infrastructure are now focused on using an innovative material called polyurea. Distinguished by its rapid curing time and versatile applications, polyurea is applied using a spray gun with high-pressure pumps. The introduction of new building materials is part of ongoing efforts to meet stringent environmental, health, and performance standards, and polyurea offers significant improvements by eliminating solvents and volatile organic compounds (VOCs). This paper presents a technological protocol starting with inspection and cleaning, followed by drying, and ending with the application of three layers: a moisture-blocking base layer, a rigid polyurethane middle layer for structural reinforcement, and a final sealing and anti-corrosion layer. This innovative method ensures a homogeneous, seamless structure, enhances construction durability, and accelerates the repair process, allowing immediate resumption of operation. Designed specifically for aggressive wastewater environments, this system is characterized by excellent corrosion resistance, making it ideal for water and wastewater infrastructure elements such as reinforced concrete manholes, sewage pumping stations, and tanks. Customizable polyurea properties allow personalization based on environmental aggressiveness, structure size, and abrasion resistance, representing a significant advancement in infrastructure maintenance technology. The paper showcases this modern repair and renovation method, highlighting its applications, benefits, and potential to revolutionize water and wastewater infrastructure maintenance in challenging conditions. The effectiveness of this solution is also compared with traditional methods, demonstrating the superiority of the three-layer system in terms of waterproofing, sulfuric acid resistance, monolithic structure, and application time.

3

Effect of solution annealing on corrosion resistance of austenitic stainless steels in chloride-containing environment

Zatkalíková Viera, Markovičová Lenka, Uhríčik Milan, Slezák Martin

System Safety : Human - Technical Facility - Environment

|

2024

|

Vol. 6, iss. 1

421--429

EN

Austenitic stainless steels are highly corrosion-resistant in common oxidation environments. However, aggressive chloride-containing solutions can evoke local corrosion, which performs an important risk in the safe use of these materials. This research deals with the effect of the solution annealing (1050 °C, 15 min) on the electrochemical parameters of AISI 304 and AISI 316L stainless steels. Corrosion resistance of the solution-annealed specimens is evaluated and compared to the as received specimens by the potentiodynamic polarization test performed in 1M pH neutral NaCl solution at the 20 ± 3 °C temperature. The obtained results did not clearly confirm the positive effect of solution annealing on corrosion resistance in the given aggressive solution. Although the pitting potentials indicating higher pitting corrosion resistance increased, the kinetics of the corrosion process intensified.

4

Corrosion resistance of PPTA Ni-based hardfacing layers

Górnik Monika, Lachowicz Marzena, Łatka Leszek

Materials Science Poland

|

2024

|

Vol. 42, No. 4

66--78

EN

In this study, the corrosion resistance of four different hardfacing layers in a 3.5% NaCl solution was tested. Using 316L steel as a reference material, NiCrBSi, NiCrBSi + 35 wt% WC, and NiCrCuMo were deposited onto a structural steel S235JR substrate using the plasma powder transferred arc technology and prepared samples in a disc form for testing. The purpose of this investigation was to propose an alternative material to the commonly known anti-corrosion protection product of 316L steel simultaneously with better wear resistance. Its corrosion damage mechanism was assessed based on electrochemical examination and is related to changes in the microstructure of the sample surface investigated by using a potentiostat and a scanning electron microscope. Polarization tests were carried out, which confirmed that all proposed overlayers provide effective anti-corrosion protection. For all samples, the corrosion current density did not exceed 0.3 µA/cm2, and the corrosion potential was not less than −290.9 mV, which were considered positive results.

5

Corrosion resistance of laser beam welded joints in ferritic stainless steel

Lisiecki Aleksander, Orłowski Jan, Topolska Santina

Materials Science and Welding Technologies / Technologie Materiałowe i Spawalnicze

|

2024

|

Vol. 68, No. 3

art. no. 2

EN

The primary goal of the research work was to determine the corrosion resistance of laser beam-welded joints made of ferritic stainless steel X2CrTiNb18 (1.4509) having a thickness of 1.5 mm. In some of the test joints, the weld was subjected to rolling. In addition, some other joints were subjected to heat treatment involving the use of a prototype induction heating welding station. The research work-related test results revealed that the test joints with the weld subjected to rolling were characterised by a significantly lower rate of linear corrosion progression (linear corrosion rate Vp = 0.008672 mm/year) compared to the test joints only subjected to laser beam welding and those subjected to heat treatment (Vp = 0.011052 mm/ year).

PL

Głównym celem badań było określenie odporności korozyjnej złączy blach ze stali nierdzewnej ferrytycznej X2CrTiNb18 (1.4509) o grubości 1,5 mm spawanych laserowo. Część złączy próbnych poddano operacji rozwalcowania spoiny, a część dodatkowo obróbce cieplnej na prototypowym stanowisku z nagrzewaniem indukcyjnym. Badania wykazały, że złącza próbne poddane operacji rozwalcowania spoiny wykazują wyraźnie niższą szybkość liniowego postępowania korozji (liniowa szybkość postępowania korozji Vp = 0,008672 mm/rok) w porównaniu ze złączami próbnymi spawanymi wyłącznie laserowo oraz z tymi poddanymi obróbce cieplnej (Vp = 0,011052 mm/rok).

6

Polydopamine coating effectively prevents early-stage corrosion of pure magnesium in tissue culture medium

Kitada Kotomi, Yoshitomi Sayuki, Sugiyama Minori, Morishige Taiki, Kakinoki Sachiro

Engineering of Biomaterials

|

2024

|

vol. 27, no. 172

art. no. 05

EN

Pure magnesium, free from toxic elements, has been identified as a promising candidate for bioabsorbable orthopaedic devices. However, its rapid corrosion in physiological environments presents a significant challenge for practical applications. Chemical coatings, such as polydopamine (PDA), offer a potential solution to improve the corrosion resistance of pure magnesium. Nevertheless, the reaction conditions must be meticulously optimized, particularly in the presence of salts, as magnesium is highly sensitive to environmental factors. In this study, a PDA coating, widely investigated for improving the corrosion resistance of magnesium alloys, was applied to pure magnesium, avoiding the conventional Tris-HCl buffer. Instead, a 0.01 mol/L NaOH aqueous solution was used successfully to coat PDA layer on the surface of pure magnesium. The corrosion behaviour of PDA-coated magnesium was evaluated using electrochemical measurements and magnesium ion elution profiles in a tissue culture medium containing 5 vol% of fetal bovine serum at 37ºC. The results demonstrated that the PDA coating effectively mitigated early-stage corrosion of the pure magnesium substrate. This method provides a straightforward approach to enhancing the corrosion resistance of pure magnesium, and the PDA layer can also function as an intermediate platform for further biofunctional surface modifications, potentially expanding its applications in biomedical fields.

7

Improved Thermal Stability of Al-Si Alloy Coated Steel Sheet with Cr Thin Film Deposition

Kim Jae-Hyeon, Lee Jung-Ha, Lee Seung-Beop, Kim Sung-Jin, Oh Min-Suk

Archives of Metallurgy and Materials

|

2024

|

Vol. 69, iss. 1

117--121

EN

We investigated the effect of Cr thin film deposition on the thermal stability and corrosion resistance of hot-dip aluminized steel. A high-quality Cr thin film was deposited on the surface of the Al-9 wt.% Si-coated steel sheets by physical vapor deposition. When the Al-Si coated steel sheets were exposed to a high temperature of 500℃, Fe from the steel substrate diffused into the Al-Si coating layer resulting in discoloration. However, the highly heat-resistant Cr thin film deposited on the Al-Si coating prevented diffusion and surface exposure of Fe, improving the heat and corrosion resistances of the Al-Si alloy coated steel sheet.

8

Study of waterproof ability and corrosion resistance of basalt fiber‑reinforced concrete with superhydrophobic surfaces

Li Yunfeng, Wang Qing, Hou Chen, Song Qingnan, Zhang Rui, Wang Ning

Archives of Civil and Mechanical Engineering

|

2024

|

Vol. 24, no. 2

art. no. e93, 2024

EN

Basalt fiber-reinforced concrete (BFRC) is used extensively in bridge engineering. However, seawater can cause the cracking of BFRC bridge concrete and the corrosion of steel reinforcement inside the concrete. In this study, an efficient fabrication method of the superhydrophobic surface of BFRC was used to improve its durability. BFRC has high surface compactness, and sodium stearate can play a better role as a modifier. Through the orthogonal study, superhydrophobic BFRC was prepared, and the effects of three major factors (temperature, time, and concentration) on the wettability of BFRC were investigated. The soaking time and solution concentration were more significant than any other factor. The capillary water absorption of the superhydrophobic BFRC was reduced compared to the BFRC. In addition, the soaking method could improve BFRC corrosion resistance by analyzing the equivalent circuit. The soaking method could improve the durability of BFRC effectively. Meanwhile, BFRC with a superhydrophobic surface had self-cleaning performance and good mechanical robustness. This research extends the scope and field of BFRC and provides technical support for utilizing the existing building.

9

Effect of heat input in dissimilar friction stir welding of A390-10 wt.% SiC composite–AA2024 aluminum alloy

Aval Hamed Jamshidi

Archives of Civil and Mechanical Engineering

|

2024

|

Vol. 24, no. 3

art. no. e172, 2024

EN

This study investigates the impact of heat input, generated during friction stir welding, on the microstructure, mechanical properties, and corrosion resistance of dissimilar joints between A390-10 wt.% SiC composite and AA2024-T6 aluminum alloy. Welds were created using two rotational speeds: 600 rpm and 1600 rpm, while maintaining a constant traverse speed of 60 mm/min and employing a triangular pin tool. The results reveal that increasing the heat input from 125 to 354 J/mm leads to enhanced mixing in the stir zone, resulting in the formation of a layered structure. The stir zone area increases by 23% with the rise in heat input from 125 to 354 J/mm. Moreover, as the heat input and plastic strain in the stir zone increase, the particle size decreases by 31%, and their distribution becomes more uniform. Furthermore, an increase in heat input leads to the formation of coarser precipitates and particles on both the advancing and retreating sides, regardless of the type of precipitates formed. Conversely, reducing the heat input from 354 to 125 J/mm results in achieving maximum hardness (165.3 ± 2.3 HV0.1), yield strength (410.3 ± 11.3 MPa), ultimate tensile strength (514.5 ± 10.4 MPa), and minimum corrosion rate (0.41 mm/year).

10

Experimental investigation on corrosion behaviour of heat-treated API X70 pipeline steel

Sharma Lochan, Dhiman Anurag, Jakhar Amman, Sharma Kanika

Advances in Materials Science

|

2024

|

Vol. 24, nr 2(80)

70--91

EN

In present study mass loss behaviour of base metal and heat-treated API X70 pipeline steel in different environments such as fresh water, sea water and sodium thiosulphate medium were observed for 50 days. Corrosion is the main failure in pipeline steel which need to be reduced with the use of suitable heat treatment process. In present study two heat treatment such as HT-1 900 ̊C (2 hour) with tempering at 450 ̊C (4 hour) and HT-2 800 ̊C (2 hour) with tempering at 450 ̊C (4 hour) was used. Mechanical, microstructure and corrosion rate of HT-1 and HT-2 specimen in different environments were observed. Maximum corrosion rate (0.306 mm/y) in fresh water while minimum corrosion rate (0.181 mm/y) in sodium thiosulphate medium was observed for base metal. Maximum corrosion rate (0.224 mm/y) in sodium thiosulphate while minimum corrosion rate (0.106 mm/y) in fresh water medium was observed for HT-1 specimen. For HT-2 specimen, Maximum corrosion rate (0.192 mm/y) in sea water while minimum corrosion rate (0.099 mm/y) in fresh water medium was observed. For HT-2 specimen, maximum average hardness of (30.3 HRC) in sea water while minimum average hardness of (28 HRC) of base metal was observed. In fresh water also HT-2 specimen, maximum average hardness is (26.3 HRC) while minimum average hardness of (24.6 HRC) of base metal was observed. After that maximum average hardness of base metal (26.6 HRC) in sodium thiosulphate while minimum average hardness of (21 HRC) of HT-2 specimen was observed.

11

Influence of sterilization and exposure to the Ringer’s solution on physicochemical properties of nitrocarburized 316 LVM steel

Kajzer Anita, Gołombek Klaudiusz, Ziębowicz Bogusław, Borowski Tomasz

Acta of Bioengineering and Biomechanics

|

2024

|

Vol. 26, no. 3

61--73

EN

The aim of the study was to investigate the influence of the nitrocarburizing process carried out in low temperature plasma using the active screen at 440 °C on the structure and physicochemical properties of the 316LVM steel. Methods: In the paper, results of microstructure and phase composition of the layers, roughness, and surface wettability, potentiodynamic pitting corrosion resistance, penetration of ions into the solution as well as biological tests were present. The studies were conducted for the samples of both mechanically polished and nitrocarburized surfaces, after sterilization, and exposure to the Ringer’s solution. Results: Based on the obtained results, the influence of sterilization and exposure to Ringer’s solution on the physicochemical properties of the surface of both the substrate and the layer were determined. The formation of a nitrocarburizing layer resulting in a favorable increase in the tested parameters was observed. Conclusions: In the conclusion, the suitability of the proposed 316LVM steel surface treatment method for short-term implants can be confirmed.

12

The influence of carbide reinforcement on the properties of sintered aluminium alloy matrix composites

Szewczyk-Nykiel Aneta

Technical Transactions

|

2023

|

Vol. 120, iss. 1

art. no. e2023005

EN

Based on the commercial aluminium alloy powder blend (Alumix 431D) metal matrix composites reinforced with particles of SiC as well as TiC were produced by conventional powder metallurgy technology and the effect of the type and amounts of reinforced particles on the selected properties and microstructure of sintered composites were investigated. In particular, the densification behaviour, the wear resistance and the corrosion resistance in 3.5% NaCl solution were identified. It was stated that both the type and the weight fraction of carbide used as particulate reinforcement have a great impact on the properties of aluminium alloy matrix composites. It was shown that the introduction of titanium carbide has a more favourable effect on the properties of sintered Alumix 431D matrix composites in comparison to silicon carbide and the optimum content of TiC in composite is 4 wt. % due to the highest hardness, wear resistance (wear rate of 2.865·10 ̄ ³ mm³/m) and simultaneously the best corrosion resistance (corrosion rate of 0.005 mm/year).

13

Paint coatings in military applications general characteristics

Michalski Marek

System Safety : Human - Technical Facility - Environment

|

2023

|

Vol. 5, iss. 1

285--293

EN

The article presents an overview of research conducted on the development of camouflage coating systems in the range of ultraviolet, visible, near infrared and radar waves, as well as operational tests of these systems. Among other things, the influence of temperature on coating systems and tests in chambers with cyclically changing conditions is presented.

14

Properties of WC-Co coatings with Al2O3 addition

Radek Norbert

Production Engineering Archives

|

2023

|

Vol. 29, Iss. 1

94--100

EN

Properties of WC-Co coatings with Al2O3 addition on the C45 mild steel surface in acidic chloride solution were examined. The WC-Co-Al2O3 coatings on steel surfaces were deposited by an electro-spark (ESD) technique. The anti-corrosion properties of the coatings were mainly investigated by electrochemical methods. Moreover, the scanning electron microscope (SEM) was employed for the observation of the surface of materials. The structure of coatings depended on the composition of electrospark electrodes. In the WC80-Co5-Al2O315 coating, the largest corrosion resistance was shown. The corrosion rate of the specimen was approximately eight times smaller than the coating with out of Al2O3 addition. The aim of the research was to obtain, by adding alumina, an improvement in the functional properties of WC-Co coatings produced by the ESD method. Due to the original features of ESD coatings, they can be used in sliding friction pairs and as anti-wear coatings on cutting tools. C-Co coatings with AlO3 addition.

15

Zinc and graphene oxide composites as new protective coatings for oil and gas pipes

Asghar M. Sajid Ali, Amir Muhammad, Hussain Umer, Sabri Mohammed M.

Polimery

|

2023

|

Vol. 68, nr 7-8

378--385

EN

A method was developed to obtain a durable coating consisting of zinc and graphene oxide (Zn-GO) in order to reduce the mechanical wear and tear rate of oil and gas pipelines made of steel. Graphene oxide was obtained from graphite by wet chemical oxidation (unmodified and modified Hummers’ method) using potassium permanganate and sulfuric acid. The process was carried out at various temperatures. The steel was covered with an ultrathin layer of Zn-GO using the electrophoretic deposition method. The GO particle size (< 90 nm) was confirmed by XRD and laser analysis. For GO particles obtained by the modified Hummers’ method, a significant correlation was observed in the scratch (R2 = 0.87) and the Vickers microhardness tests (R2 = 0.93), which indicates a lower wear rate of Zn-GO-coated steel.

PL

Opracowano metodę otrzymywania trwałej powłoki składającej się z cynku i tlenku grafenu (Zn-GO) w celu zmniejszenia zużycia mechanicznego rurociągów naftowo-gazowych wykonanych ze stali. Tlenek grafenu pozyskano z grafitu metodą mokrego utleniania chemicznego (niezmodyfikowana i zmodyfikowana metoda Hummersa) z użyciem nadmanganianu potasu i kwasu siarkowego. Proces prowadzono w różnej temperaturze. Stal powlekano ultra cienką warstwą Zn-GO techniką osadzania elektroforetycznego. Metodą XRD i analizą laserową potwierdzono wielkość cząstek GO (≤ 90 nm). Dla cząstek GO otrzymanych zmodyfikowaną metoda Hummersa zaobserwowano znaczącą korelację w teście zarysowania (R2 = 0.87) i mikrotwardości Vickersa (R2 = 0.93), co świadczy o mniejszym stopniu zużycia stali pokrytej powłoką Zn-GO.

16

Performance of green high-strength concrete incorporating palm oil fuel ash in harsh environments

Zeyad Abdullah M., Johari Megat Azmi Megat, Aliakbar Ali, Magbool Hassan M., Majid Taksiah A., Aldahdooh Majed A. A.

Materials Science Poland

|

2023

|

Vol. 41, No. 4

24--40

EN

The corrosion of steel reinforcement by chloride is commonly recognized as a key factor that contributes to the degradation of durability in reinforced concreae structures. Using supplementary cementitious materials, such as industrial and agricultural waste materials, usually enhances the impermeability of the concrete and its corrosion resistance, acid resistance, and sulfate resistance. This study’s primary purpose is to examine the effects of replacing ordinary Portland cement (OPC) with ultrafine palm oil fuel ash (U-POFA) on the corrosion resistant performance of high-strength green concrete (HSGC). There were four HSGC mixes tested; the first mix contained 100% OPC, while the other mixes replaced OPC mass with 20%, 40%, and 60% of U-POFA. The performance of all HSGC mixes containing U-POFA on workability, compressive strength, porosity, water absorption, impressed voltage test, and mass loss was investigated at 7, 28, 60, and 90 days. Adding U-POFA to mixes enhances their workability, compressive strength (CS), water absorption, and porosity in comparison with mixes that contain 100% OPC. The findings clearly portrayed that the utilization of U-POFA as a partial alternative for OPC significantly enhances the corrosion-resistant performance of the HSGC. In general, it is strongly advised that a high proportion of U-POFA be incorporated, totaling 60% of the OPC content. This recommendation is the result of its significance as an environmentally friendly and cost-effective green pozzolanic material. Hence, it could contribute to the superior durability performance of concrete structures, particularly in aggressive environmental exposures.

17

Effects of B content on wear and corrosion resistance of laser-cladded Co-based alloy coatings

Xia Rong, Zhang Kun, Shu Fengyuan, Zhang Xin, Yan Liying, Li Cheng

Materials Science Poland

|

2023

|

Vol. 41, No. 4

13--23

EN

To improve the surface properties of Ti alloy, (Co34Fe8Cr29Ni8Si7)100–x Bx alloy, coatings were prepared by laser cladding. The coatings—mainly composed of TiCr, Fe0.1Ti0.18V0.72, CoTi, Ti2Ni, and TiB—and amorphous phases were investigated in terms of microstructure, wear resistance, and corrosion resistance. The results showed that the microhardness of the Co-based coatings first increased and then decreased with the increase of B content. When the B content was 6%, the microhardness of the coating increased up to 1210 HV0.2 which was 3.4 times that of TC4 alloy substrate. The coatings exhibited diverse wear mechanisms that gradually transitioned from severe fatigue spalling and oxidative wear to slightly abrasive wear. The corrosion current density of Co-based coatings in 3.5 wt% NaCl solution first increased and then decreased as B contents increased. Coatings with 4% B content, however, exhibited the best corrosion resistance, which was most suitable for improving the corrosion resistance of Ti alloy.

18

Influence of annealing conditions on changes of the structure and selected properties of Al88Y7Fe5 and Al88Y6Fe6 alloys

Babilas Rafał, Spilka Monika, Łoński Wojciech, Radoń Adrian, Kądziołka-Gaweł Mariola, Gębara Piotr

Bulletin of the Polish Academy of Sciences. Technical Sciences

|

2023

|

Vol. 71, nr 2

art. no. e144614

EN

Al-Y-Fe amorphous and nanocrystalline alloys are characterized by a unique collection of diverse properties that are influenced by various factors, including heat treatment. In this paper, the effect of heat treatment on the structural changes and selected properties of Al-Y-Fe metallic glasses in the as-spun state is investigated. The structure of the Al88Y7Fe5 and Al88Y6Fe6 alloys was examined by X-ray diffraction (XRD) and Mössbauer spectroscopy (MS). The corrosion resistance of the samples was characterized using polarization tests in a 3.5% NaCl solution at 25 °C. The effect of sodium chloride on the surface was studied with scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). The magnetic properties of Al-based alloys were explored using a vibrating sample magnetometer (VSM). It was revealed that the tested alloys show better properties after annealing than in the as-spun state. The annealing of the Al88Y7Fe5 and Al88Y6Fe6 alloys in the temperature range of 200 to 300 °C improved the magnetic properties and corrosion resistance of these materials. After 3,600 s, the better EOCP values were recorded for the Al88Y6Fe6 and Al88Y7Fe5 alloys after annealing at 300 °C and 200 °C, adequately. On the basis of the polarization tests, it was concluded that the electrochemical properties are better for Al88Y6Fe6 alloys after annealing at 300 °C.

19

Effect of spray distance on the microstructure and corrosion resistance of WC - based coatings sprayed by HVOF

Jonda Ewa, Łatka Leszek, Maciej Artur, Godzierz Marcin, Gołombek Klaudiusz, Radziszewski Andrzej

Bulletin of the Polish Academy of Sciences. Technical Sciences

|

2023

|

Vol. 71, nr 2

art. no. e144610

EN

Cermet coatings provide protection against aggressive operating environment of machine and device elements, such as corrosion, wear or high-temperature conditions. Currently WC-based cermet coatings are frequently used in the different industry branches. In this work, conventional WC-based powders (WC-Co and WC-Co-Cr) were sprayed with High Velocity Oxy Fuel (HVOF) onto AZ31 magnesium alloy with different spray distances (320 and 400 mm). The aim of the research was to investigate the effect of the spray distance on the microstructure of the coatings, phase composition and electrochemical corrosion resistance. Results revealed that higher spray distance results in greater porosity, 1.9% and 2.3% for 320 mm and 2.8% and 3.1% for 400 mm in case of WC-Co and WC-Co-Cr coatings, respectively. Also the influence has been observed for coatings microhardness, c.a. 1300 HV0.3 for shorter spray distance, whereas for longer one it was less than 1100 HV0.3. The corrosion resistance estimated in potentiodynamic polarization measurements was the best for WC-Co-Cr coating deposited from the shorter spray distance, corrosion current density was equal to 2.9 µA·cm-2 and polarization resistance was equal to 8424 Ω∙cm2.

20

Mechanical Properties, Machinability and Corrosion Resistance of Zamak5 Alloyed by Copper

Al Aboushi Ahmad, Al-Qawabah Safwan, Abu Shaban Nabeel, Al-Rawajfeh Aiman Eid

Archives of Metallurgy and Materials

|

2023

|

Vol. 68, iss. 4

1391--1399

EN

Due the importance of using commercially Zamak5 in a wide range in industrial applications, however, this study was focused on the enhancing its machining issues by adding pure copper, so the effect of the addition of (1 to 3)% Cu to commercially Zamak5 on its mechanical properties, microhardness, surface texture and corrosion resistance was investigated. A CNC machining tests, microhardness tests, corrosion test, compression test, and microhardness test were performed. It was found that there is an enhancement on the flow stress at 0.2 strain of about 19% for 3% Cu addition followed by 17% and 15% in the case of 2% Cu and 1% Cu respectively. There was an enhancement in microhardness of about 11.6% in the case of 3% Cu addition. The surface finish was improved by increasing the number of copper contents (1 to 3)% to the base material Za5. Polarization measurements revealed that 3% alloy specimen inhibit the corrosion by more than 70% compared with the blank sample.