Effect of Annealing on the Properties of Surface Nanocrystallized CP-Ti

2011 ◽  
Vol 695 ◽  
pp. 162-165
Author(s):  
Cong Hui Zhang ◽  
Xiao Mei He ◽  
Xin Zhe Lan ◽  
Xi Cheng Zhao
Keyword(s):  
Corrosion Resistance ◽  
Polarization Curve ◽  
Annealing Temperature ◽  
Vacuum Annealing ◽  
Optical Microscope ◽  
Nanostructured Surface ◽  
Before And After ◽  
Different Temperatures ◽  
Cp Ti ◽  
Better Than

Vacuum annealing was carried out for the SMAT treated CP-Ti sample at different temperatures. The structure and the properties of the SMAT sample before and after the annealing were analyzed by means of the optical microscope, hardness and polarization curve testing. The results show that, when the annealing temperature of surface nanocrystallized CP-Ti treated CP-Ti (SMAT) was below 350°C, the microstructure and hardness of nanostructured surface was stability, and its corrosion resistance was improved compared to non-annealing one. In particular, the corrosion resistance at 150°C was better than that of the original CP-Ti.

Magnetron Sputtering High Temperature Mo-Al2O3 Cermet Solar Selective Coatings

2007 ◽  
Vol 546-549 ◽  
pp. 1773-1776 ◽  
Author(s):  
Xin Kang Du ◽  
Cong Wang ◽  
Tian Min Wang ◽  
Bu Liang Chen ◽  
Long Zhou ◽  
...  
Keyword(s):  
Room Temperature ◽  
Annealing Temperature ◽  
Vacuum Annealing ◽  
Layer Structure ◽  
Steel Substrate ◽  
Annealing Treatment ◽  
Solar Absorptance ◽  
Selective Coating ◽  
Before And After ◽  
Different Temperatures

Based on double cermet layer structure, Mo-Al2O3 cermet solar selective coating was prepared on stainless steel substrate. A solar absorptance of 0.92 and normal emittance of 0.19 at room temperature have been achieved. Vacuum annealing treatment was done and its influences on the solar selective performance was discussed. Absorptance changed between 0.90 and 0.92 under the selected annealing temperature range of 350-800°C, and emittance varied from 0.19 to 0.23 when heated at 650°C. The microstructures before and after annealing process at different temperatures were investigated.

scholarly journals Effect of Mn Content and Solution Annealing Temperature on the Corrosion Resistance of Stainless Steel Alloys

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Ihsan-ul-Haq Toor
Keyword(s):  
Corrosion Resistance ◽  
Annealing Temperature ◽  
Electrochemical Impedance ◽  
Austenitic Stainless Steels ◽  
Electrochemical Tests ◽  
Linear Polarization Resistance ◽  
Ni Content ◽  
Different Temperatures ◽  
Acidic Chloride ◽  
Mn Content

The corrosion behavior of two specially designed austenitic stainless steels (SSs) having different Nickel (Ni) and Manganese (Mn) contents was investigated. Prior to electrochemical tests, SS alloys were solution-annealed at two different temperatures, that is, at 1030°C for 2 h and 1050°C for 0.5 h. Potentiodynamic polarization (PD) tests were carried out in chloride and acidic chloride, whereas linear polarization resistance (LPR) and electrochemical impedance spectroscopy (EIS) was performed in 0.5 M NaCl solution at room temperature. SEM/EDS investigations were carried out to study the microstructure and types of inclusions present in these alloys. Experimental results suggested that the alloy with highest Ni content and annealed at 1050°C/0.5 hr has the highest corrosion resistance.

Effect of Shot Peening on Microstructure and Properties of 34CrMo4 Alloy

2018 ◽  
Vol 934 ◽  
pp. 105-110 ◽  
Author(s):  
Ke Jian Li ◽  
Qiang Zheng ◽  
Yue Lin Qin ◽  
Xiao Wei Liu
Keyword(s):  
Plastic Deformation ◽  
Corrosion Resistance ◽  
Shot Peening ◽  
Electrochemical Impedance ◽  
Corrosion Current ◽  
Optical Microscope ◽  
Microstructure And Properties ◽  
Before And After ◽  
Sever Plastic Deformation ◽  
Evolution Of Microstructure

Plastic deformation can induce surface modification, such as shot peening (SP) on workpiece surface is the hot issue of recent scientific research. SP is the efficient way to improve mechanical behavior of specimens by inducing sever plastic deformation on their surface. Nevertheless, this surface treatment induced complex microstructural evolutions such as grain refinement, will enhance the corrosion resistance of specimens. In this work, the microstructure and properties of 34CrMo4 alloy of before and after SP for 20 min have been investigated. The evolution of microstructure and properties were analyzed from the surface and cross-section. The microstructure morphology at the different depth was determined by optical microscope. The results show grain size is increasing with the depth, and the microhardness and compressive residual stress decrease gradually. In terms of corrosion resistance, the 50 μm depth specimen has the best property than other depth, which the potential and corrosion current density are-0.484 V and-5.72 Acm-2, respectively. The maximum polarization resistance is 2055 Ωcm2by capacitive arc radius of electrochemical impedance spectroscopy.

scholarly journals Corrosion Resistance of Ti-6Al-4V Machined Surfaces Improved by Thermal Oxidation

2020 ◽  
Vol 24 (5) ◽  
pp. 185-193
Author(s):  
Carolina Aurélia Ribeiro Maestro ◽  
Marina Cristina Ferreira ◽  
Alysson Helton Santos Bueno ◽  
Artur Mariano de Sousa Malafaia
Keyword(s):  
Corrosion Resistance ◽  
Thermal Oxidation ◽  
Body Fluid ◽  
Vickers Microhardness ◽  
The Other ◽  
Machining Parameters ◽  
Before And After ◽  
Economical Process ◽  
Better Than ◽  
Machined Surfaces

Ti-6A-l4V alloy is widely used in implants and prosthesis applications. Although machining is a fast and economical process, the roughness generated can compromise corrosion resistance. Thus, the goal of this study was to overcome this limitation using thermal oxidation in machined surfaces. Samples with polished surfaces were used for comparison purposes. Two sets of machining parameters were used to generate different roughness, property evaluated in polished and machined samples before and after thermal oxidation. Vickers microhardness and polarization tests using simulated body fluid (SBF) were also performed. Thermal oxidation generated similar microhardness for polished and machined samples, higher than for polished and non-oxidized condition. On the other hand, oxidation increased the roughness only for polished condition. The corrosion resistance was improved in all oxidized samples, and the best result was found to the intermediate roughness (Ra = 0.76 um), in a machined sample. The results demonstrated that thermal oxidation can be used to overcome machining limitations regarding corrosion resistance, achieving behavior even better than polished samples.

Preparation of Al Coating on Mg-Li Alloy with Molten Salt Replacement

2014 ◽  
Vol 644-650 ◽  
pp. 4798-4801 ◽  
Author(s):  
Zhong Yi Niu ◽  
Zhi Kun Qu ◽  
Ting Tao Ma ◽  
Xiao Yan Jing
Keyword(s):  
Corrosion Resistance ◽  
Phase Composition ◽  
Molten Salt ◽  
Electrochemical Analysis ◽  
Treatment Temperature ◽  
Optimal Treatment ◽  
Different Temperatures ◽  
Al Coating ◽  
Better Than

A method of molten salt replacement was used to prepare an Al coating on Mg-Li alloy at different temperatures. The thickness, microstructure, phase composition and corrosion electrochemical analysis of the coating treated at different temperatures were analyzed. The corrosion resistances of the specimens with and without optimal coating were comparatively evaluated. Results show that, the optimal treatment temperature is 350 °C, at which a thickness of 9.15 μm coating is formed. In the Al coatings, Al exists as the form of Mg17Al12 and AlLi. The corrosion resistance is much better than that of the specimen without coating.

scholarly journals Compatibility between C6F12O–N2 Gas Mixture and Metal Used in Medium-Voltage Switchgears

Energies ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4639
Author(s):  
Ran Zhuo ◽  
Qi Chen ◽  
Dibo Wang ◽  
Mingli Fu ◽  
Ju Tang ◽  
...  
Keyword(s):  
Gas Mixture ◽  
Copper Sheet ◽  
Surface Color ◽  
Practical Applications ◽  
Medium Voltage ◽  
Before And After ◽  
Different Temperatures ◽  
Potential Alternative ◽  
Better Than

C6F12O has been introduced as the potential alternative gas to SF6 because of its excellent insulation properties and great eco-friendly performance. Considering that C6F12O may react with the internal materials of switchgears in practical applications, its compatibility with metal materials must be tested to evaluate its long-term application possibilities. In this work, the compatibility of C6F12O–N2 gas mixtures with aluminum and copper was tested at different temperatures by setting up a heat-aging reaction platform between the gas and each metal. The metal surface morphology and gas composition before and after the reaction were compared and analyzed. The results show that the surface color of the copper sheet changed considerably, and the corrosion degree of the surface deepened with the increase of temperature. The decomposition of C6F12O was also promoted. In contrast, aluminum did not react severely with the gas mixture. The compatibility of the gas mixture with aluminum was generally better than that of copper.

Banana Trunk as Green Corrosion Inhibitor for Carbon Steel in Subsea Applications

2015 ◽  
Vol 1087 ◽  
pp. 227-231 ◽  
Author(s):  
Azzura Ismail ◽  
Anis Nazihah Mat Nawi
Keyword(s):  
Carbon Steel ◽  
Corrosion Rate ◽  
Static Condition ◽  
Optical Microscope ◽  
Electrochemical Test ◽  
Green Inhibitor ◽  
Tafel Polarization ◽  
Before And After ◽  
Different Temperatures ◽  
Predetermined Time

Corrosion is a serious problem in every industry and can cause losses in production leading to large financial losses. International legisation body has drawn offshore chemical into several categoris based on biodegradation, bioaccumulation and toxicity. Otherwise, the inhibitor is not accept to be used as they are harmful to environment. Therefore, most industries are looking for green inhibitor for An electrochemical test has been carried out to determine the corrosion rate of carbon steel. This research aimed to investigate the potential corrosion of carbon steel in seven different immersion periods ( 1 day, 2 days, 7 days, 14 days, 21 days , 28 days, 35 days) using seawater 3.5 % NaCl. The pH values were set in neutral in static condition. The materials were run for tafel polarization with a scan rate of 0.5mV/sec. Each sample will be tested when achieve a predetermined time. This experiment was carried out to compare the corrosion rate of 3.5% NaCl and with NaCl added 25% inhibitor. Inhibitors used were from banana trunk. The experiments were carried out at four different temperatures (5°C, 10°C, 20°C and 30°C). Before and after testing, the microstructures of each sample were observed by using Optical Microscope (OM). The results show the highest corrosion rate occurring in the shortest period of immersion for 1 day. However, the corrosion rate decreases when the longer period of immersion. The corrosion rate for 3.5% NaCl will increase with added 25% inhibitor and decrease for 3.5% NaCl when temperature decreases.

Microstructure and Properties of TA1 TIG Joint via Micro-Arc Oxidation

2015 ◽  
Vol 1120-1121 ◽  
pp. 1287-1291
Author(s):  
Yu Peng Guo ◽  
Shi Chun Di ◽  
Hong Wei Lv
Keyword(s):  
Corrosion Resistance ◽  
Phase Composition ◽  
Base Metal ◽  
Polarization Curve ◽  
Corrosion Potential ◽  
Optical Microscope ◽  
Joint Surface ◽  
Coating Morphology ◽  
Micro Arc Oxidation ◽  
Oxidation Technology

This paper applied the micro-arc oxidation technology to TIG weld joint based on titanium alloy. The optical microscope, SEM, XRD and polarization curve were used to analyze the joints metallographic phase, the coating morphology, the phase composition and corrosion resistance. Research results showed that the grain was grew gradually coarser from base metal to joint. The joint surface obtained a uniform morphology after micro-arc oxidation. The joint and base metal was made up of α-Ti and their coatings are mainly composed by rutile-TiO2. The surface morphology and phase composition are similar after micro-arc oxidation. Polarization curve tests demonstrated that the corrosion potential performance of the coating was enhanced by micro-arc oxidation.

Effect of High-Pressure Solution Temperature on Corrosion Resistance of AM60 Magnesium Alloy

2012 ◽  
Vol 580 ◽  
pp. 560-563
Author(s):  
Guang Hui Chen
Keyword(s):  
High Pressure ◽  
Corrosion Resistance ◽  
Magnesium Alloy ◽  
Solution Treatment ◽  
Optical Microscope ◽  
Solution Temperature ◽  
Pressure Solution ◽  
Different Temperatures ◽  
Increasing Temperature

As-cast AM60 magnesium alloy was solid dissolved under a high-pressure of 4 Gpa at different temperatures. The microstructure of the products was observed by optical microscope and the corrosion resistance of the products was investigated. The results show that increasing temperature during solution treatment promotes the dissolution into α-Mg matrix of β-Mg17Al12 in the alloy and improves the corrosion resistance of AM60 alloy, especially for over 400 °C.

Effect of Dissolution of Oxide Film on Oxidation of Zr-1%Nb Alloy in Air and Pressurized Steam at 450 C

CORROSION ◽  
1970 ◽  
Vol 26 (4) ◽  
pp. 131-134
Author(s):  
I. A. EL-SHANSHOURY ◽  
M. E. EL-DAHSHAN
Keyword(s):  
Activation Energy ◽  
Corrosion Resistance ◽  
Corrosion Rate ◽  
Oxide Film ◽  
Corrosive Medium ◽  
Oxidation Rate ◽  
Treatment Process ◽  
Annealing Temperature ◽  
Vacuum Annealing ◽  
Oxygen Ion

Abstract The corrosion behavior of oxidized and vacuum annealed Zr-1%Nb alloy was investigated at 450 C (842 F) in air and pressurized steam. The corrosion resistance of partially dissolved oxide films was found to decrease with the increase in the vacuum annealing temperature up to 600 C (1112 F). A linear relationship between the logarithm of the oxidation rate and the annealing temperature was obtained from which an activation energy of 39.5 K.cal/mole was calculated. The activation energy was found to be independent of the corrosive medium. The increase in corrosion rate is explained on the fact that oxygen ion vacancy gradient increases with the increase in the annealing temperature. The decrease of the corrosion rate in steam after vacuum annealing is attributed to the release of H2 and H during the treatment process.

Sign in / Sign up

Export Citation Format

Share Document