Effect of Heat Treatment on Microstructure and Corrosion Resistance of Ni-Cr-Mo-Fe Alloys

2012 ◽  
Vol 581-582 ◽  
pp. 773-776
Author(s):  
Er Chao Ding ◽  
Zhen Yong Man ◽  
Xin Xin Yang ◽  
Jing Tai Zhao
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Electrochemical Analysis ◽  
X Ray Diffraction ◽  
Homogeneous Microstructure ◽  
X Ray ◽  
Arc Melting ◽  
Distribution Of Elements ◽  
Microstructure Morphology ◽  
Fe Alloys

The effects of heat treatment on microstructure and corrosion resistance of Ni-Cr-Mo-Fe nickel-based alloys were investigated by X-ray diffraction (XRD), metallographic microscope (MM), scanning electron microscopy (SEM) and electrochemical analysis, respectively. Experimental results indicated that the samples which were prepared via electric arc melting shielded by argon were pure solid solutions with homogeneous microstructure. Segregation of chromium element and slightly smaller grain size were found after heat treatment. Better corrosion resistance of samples was achieved after heat treatment, due to improvement of microstructure, morphology and distribution of elements.

scholarly journals Nanomechanical Behavior, Adhesion and Corrosion Resistance of Hydroxyapatite Coatings for Orthopedic Implant Applications

Coatings ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 477
Author(s):  
Kaouther Khlifi ◽  
Hafedh Dhiflaoui ◽  
Amir Ben Rhouma ◽  
Joël Faure ◽  
Hicham Benhayoune ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
X Ray Diffraction ◽  
Homogeneous Microstructure ◽  
X Ray ◽  
Hydroxyapatite Coatings ◽  
Adhesion Behavior ◽  
Heat Treated ◽  
Before And After ◽  
Scratch Tests

The aim of this work was to investigate the nanomechanical, adhesion and corrosion resistance of hydroxyapatite (HAP) coatings. The electrodeposition process was used to elaborate the HAP coatings on Ti6Al4V alloy. The effect of hydrogen peroxide concentration H2O2 on the electrolyte and the heat treatment was studied. Surface morphology of HAP coatings was assessed, before and after heat treatment, by scanning electron microscopy associated with X-ray microanalysis (SEM-EDXS). Moreover, X-ray diffraction (XRD) was performed to identify the coatings’ phases and composition. Nanoindentation and scratch tests were performed for nanomechanical and adhesion behavior analysis. The corrosion resistance of the uncoated, the as-deposited, and the heat-treated coatings was investigated by electrochemical test. The obtained results revealed that, with 9% of H2O2 and after heat treatment, the HAP film exhibited a compact and homogeneous microstructure. The film also showed a crystal growth: stoichiometric hydroxyapatite (HAP) and β-tricalcium phosphate (β-TCP). After heat treatment, the nanomechanical properties (H, E) were increased from 117 ± 7 MPa and 24 ± 1 GPa to 171 ± 10 MPa and 38 ± 1.5 GPa respectively. Critical loads (LC1, LC2, and LC3) were increased from 0.78 ± 0.04, 1.6 ± 0.01, and 4 ± 0.23 N to 1.45 ± 0.08, 2.46 ± 0.14, and 4.35 ± 0.25 N (respectively). Furthermore, the adhesion strength increased from 8 to 13 MPa after heat treatment. The HAP heat-treated samples showed higher corrosion resistance (Rp = 65.85 kΩ/cm2; Icorr = 0.63 µA/cm2; Ecorr = −167 mV/ECS) compared to as-deposited and uncoated samples.

EFFECT OF HEAT TREATMENT ON MICROSTRUCTURE AND CORROSION RESISTANCE OF Ni-B-W-Mo COATING DEPOSITED BY ELECTROLESS METHOD

2018 ◽  
Vol 25 (08) ◽  
pp. 1950023 ◽  
Author(s):  
ARKADEB MUKHOPADHYAY ◽  
TAPAN KUMAR BARMAN ◽  
PRASANTA SAHOO
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Electrochemical Techniques ◽  
Sodium Molybdate ◽  
Medium Carbon Steel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solid Solution Strengthening ◽  
Heat Treated ◽  
Electroless Coatings

The present work reports the deposition of a quaternary Ni-B-W-Mo coating on AISI 1040 medium carbon steel and its characterization. Quaternary deposits are obtained by suitably modifying existing electroless Ni-B bath. Composition of the as-deposited coating is analyzed by energy dispersive X-ray spectroscopy. The structural aspects of the as-deposited and coatings heat treated at 300[Formula: see text]C, 350[Formula: see text]C, 400[Formula: see text]C, 450[Formula: see text]C and 500[Formula: see text]C are determined using X-ray diffraction technique. Surface of the as-deposited and heat-treated coatings is examined using a scanning electron microscope. Very high W deposition could be observed when sodium molybdate is present in the borohydride-based bath along with sodium tungstate. The coatings in their as-deposited condition are amorphous while crystallization takes place on heat treatment. A nodulated surface morphology of the deposits is also observed. Vickers’ microhardness and crystallite size measurement reveal inclusion of W and Mo results in enhanced thermal stability of the coatings. Solid solution strengthening of the electroless coatings by W and Mo is also observed. The applicability of kinetic strength theory to the hardening of the coatings on heat treatment is also investigated. Corrosion resistance of Ni-B-W-Mo coatings and effect of heat treatment on the same are also determined by electrochemical techniques.

Research on Properties of Amorphous Cr-C Alloy Coating in Crystallization Evolution

2012 ◽  
Vol 184-185 ◽  
pp. 1175-1180
Author(s):  
Guo Liang Li ◽  
Xiao Hua Jie ◽  
Bi Xue Yang
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Intermetallic Compound ◽  
Adhesion Force ◽  
Alloy Coating ◽  
Treatment Temperature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Proper Values ◽  
Peak Value

Amorphous Cr–C alloy coating was prepared by electrodepositing. The microhardness of the coating was tested after annealing from 100°C to 800°C and the crystallization evolution was studied by the analysis of X-ray diffraction (XRD) and differential scanning caborimetry (DSC). The results showed that the crystallization evolution of the coating began at 300°C and finished around 450°C, and intermetallic compound Cr7C3and Cr23C6appeared when heat treatment temperature reached around 600°C. The microhardness, corrosion resistance as well as the adhesion of the coating all increased first with the temperature and then dropped until it attained the proper values. The microhardness reached the maximum of 1610HV0.025at 600°C. While the corrosion resistance and the adhesion force attained the peak value at about 400°C.

scholarly journals Influence of Different Heat Treatment Temperatures on the Microstructure, Corrosion, and Mechanical Properties Behavior of Fe-Based Amorphous/Nanocrystalline Coatings

Coatings ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 858
Author(s):  
Shenglin Liu ◽  
Yongsheng Zhu ◽  
Xinyue Lai ◽  
Xueping Zheng ◽  
Runnan Jia ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Heat Treatment Temperature ◽  
Annealing Treatment ◽  
Treatment Temperature ◽  
X Ray Diffraction ◽  
Crystalline Phases ◽  
X Ray ◽  
Different Temperatures ◽  
Sprayed Coating

Fe-based amorphous/nanocrystalline coatings with smooth, compact interior structure and low porosity were fabricated via supersonic plasma spraying (SPS). The coatings showed outstanding corrosion resistance in a 3.5% NaCl solution at room temperature. In order to analyze the effect of annealing treatment on the microstructure, corrosion resistance and microhardness, the as-sprayed coating was annealed for 1 h under different temperatures such as 350, 450, 550 and 650 °C, respectively. The results showed that the number of oxides and cracks in the coatings presented an obvious increase with increasing annealing temperature, and the corrosion resistance of the coatings showed an obvious reduction. However, the microhardness of coatings showed an important increase. The microhardness of the coating could reach 1018 HV when the heat treatment temperature reached 650 °C. The X-ray diffraction (XRD) results showed that there appeared a number of crystalline phases in the coating when the heat treatment temperature was at 650 °C. The crystalline phases led to the increase of the microhardness.

Influence of Substitution of Fe by Mo on Heat Treatment Behavior in Ti-Mo-Fe Alloys

2021 ◽  
Vol 1016 ◽  
pp. 162-169
Author(s):  
Kyosuke Mizuta ◽  
Shotaro Miyake ◽  
Masahiko Ikeda ◽  
Masato Ueda
Keyword(s):  
Heat Treatment ◽  
Electrical Resistivity ◽  
Diffusion Coefficient ◽  
Vickers Hardness ◽  
Partial Substitution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Β Phase ◽  
Ti Alloys ◽  
Fe Alloys

In order to reduce the cost of β-type Ti alloys, the use of Fe as an alloying element has been studied. However, Fe is known to have a very high diffusion coefficient in β-Ti of about 2.6×10-12 m2/s at 1200 K, and its behavior during heat treatment is expected to be difficult to control. By contrast, Mo, which is also a β-stabilizing element, has a diffusion coefficient of only about 2.5×10-14 m2/s at 1200 K, i.e., roughly 100 times smaller than that of Fe1), 2). In this study, the effect of the partial substitution of Fe with Mo on the aging behavior of β-Ti alloys was investigated using X-ray diffraction, electric resistivity, and Vickers hardness measurements. Ti-Mo-Fe alloys were solution-treated by holding at 1173 K for 3.6 ks and then quenching in ice water. In the X-ray diffraction patterns for the resulting samples, only peaks associated with the β phase were identified. It was found that the electrical resistivity and Vickers hardness decreased with increasing Mo content. As the Mo-to-Fe ratio increased, the decrease in electrical resistivity and the increase in Vickers hardness occurred later during the isothermal aging process. This was due to a delay in isothermal ω-phase precipitation.

scholarly journals Heat Treatment Effect in the Corrosion Resistance of the Al-Co-Mn Alloys Immersed in 3 M KOH

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
J. G. Pereyra-Hernández ◽  
I. Rosales-Cadena ◽  
R. Guardián-Tapia ◽  
J. G. González-Rodríguez ◽  
R. López-Sesenes
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Chemical Analysis ◽  
Polarization Resistance ◽  
Electrochemical Techniques ◽  
Corrosion Current ◽  
Heat Treatments ◽  
X Ray Diffraction ◽  
X Ray ◽  
Co Concentration

Al-based alloys named M1, M2, M3, M4, and M5 doped with different atomic percentage (at%) of cobalt and manganese as cast and submitted at two heat treatments (600°C and 1100°C) were analyzed by using electrochemical techniques to evaluate their corrosion resistance immersed in 3 M KOH. With the heat treatments applied to the alloys, the sample M2 (65% Al, 20% Co, and 15% Mn) observed the highest corrosion resistance with R p values of 3.0 × 10 2 , 6.2 × 10 2 , and 1.61 × 10 3   Ω · c m 2 as cast, 600°C, and 1100°C, respectively. The latter was in agreement with the I corr calculated from the polarization curves where the values decrease based on the heat treatment applied as follows: 1.60 × 10 3 > 6.16 × 10 2 > 3.07 × 10 2   mA / c m 2 for 1100, 600, and as cast, respectively. Co concentration above 20% increases the corrosion current ( I corr ) and decreases the polarization resistance of the remain samples. The chemical analysis done with EDS and X-ray diffraction made confirmed the presence of compounds such as CoAl, Co2Al5, Co2Al9, MnAl4, and MnAl6.

Effect of Heat Treatment on the Corrosion Behaviour of a Mg-Y Alloy in Chloride Medium

2010 ◽  
Vol 636-637 ◽  
pp. 491-496 ◽  
Author(s):  
M. Carboneras ◽  
Claudio J. Múnez ◽  
Pilar Rodrigo ◽  
M. Dolores Escalera ◽  
Maria Dolores López ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Elevated Temperatures ◽  
Corrosion Behaviour ◽  
X Ray Diffraction ◽  
Chloride Medium ◽  
X Ray ◽  
Technology Applications ◽  
Mechanical Properties And Corrosion ◽  
Surface Examination

Corrosion behaviour of a Mg-Y alloy (commercial WE54) has been studied. This alloy presents excellent retention of mechanical properties and corrosion resistance at elevated temperatures, a combination of properties that can be of interest in many technology applications. To evaluate the effect of heat treatment on the corrosion resistance, WE54 samples in extruded state and after T6 heat treatment were studied. Corrosion behaviour was evaluated by electrochemical and immersion tests in 3.5 wt.% NaCl solution at room temperature and neutral pH. Surface examination was carried out by scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and X-ray diffraction (XRD). It was found that corrosion resistance of the magnesium alloy WE54 in chloride medium was improved by applying the heat treatment to the material, a fact that was correlated with the developed microstructure in T6 condition.

scholarly journals Effect of Heat Treatment on the Phase Composition and Corrosion Resistance of 321 SS Welded Joints Produced by a Defocused Laser Beam

Materials ◽  
2019 ◽  
Vol 12 (22) ◽  
pp. 3720 ◽  
Author(s):  
Sergey Vyacheslavovich Kuryntsev
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Phase Composition ◽  
Laser Beam ◽  
Welded Joints ◽  
Intergranular Corrosion ◽  
Alloying Elements ◽  
X Ray Diffraction ◽  
X Ray ◽  
Δ Ferrite

The effect of heat treatment of welded joints made of steel 321 on corrosion resistance, phase composition, residual stresses, and distribution of alloying elements was studied using optical microscope (OM) and scanning electron microscope (SEM), electron dispersive spectroscopy (EDS), X-ray diffraction (XRD), and intergranular corrosion testing (IGC). Samples previously obtained by the authors using defocused laser beam, which led to the formation of directionally crystallized austenite with lathy and skeletal δ-ferrite, were investigated. Based on X-ray diffraction studies in the base metal, the maximum number of peaks of various phases was presented, which decreased after exposure to the heating effect of the welding process and subsequent heat treatment. The distribution of alloying elements, in particular, Ti and Si, was significantly affected by heat treatment depending on the regimes. A spot chemical analysis showed that the nickel content differs in δ-ferrite and austenite by 1.5%–2% whereas the chromium content in these phases is not significantly different. Tests have shown that all samples have high resistance to intergranular corrosion, which can be explained by the insufficient dissolution of titanium carbides in austenite and the absence of chromium carbides formation along austenite grain boundaries, due to high cooling rates when welding by a defocused laser beam, and as a result, the high δ-ferrite content in which chromium dissolves.

The Effect of Heat Treatment on Corrosion Resistance of Ni-W-P-Al2O3 Composite Coating

2012 ◽  
Vol 468-471 ◽  
pp. 1177-1180
Author(s):  
Wan Chang Sun
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Composite Coating ◽  
Annealing Temperature ◽  
Steel Substrate ◽  
Optical Microscope ◽  
Amorphous Structure ◽  
Crystal Defects ◽  
X Ray Diffraction ◽  
X Ray

Abstract. Ni-W-P-Al2O3 electroless composite coating was successfully co-deposited on 45 steel substrate using electroless plating. Optical microscope (OM), X-ray diffraction (XRD) and potentiodynamic polarization were used to analyze the morphology, microstructure and corrosion resistance of the composite coating. The results show that Al2O3 particles co-deposit homogeneously, and the structure of the composite coating as deposited is amorphous and crystallite. After heat treatment, the amorphous structure of the composite coating appears a precipitation transformation. When annealing at 400°C, because of the emergence of crystal defects brought out by the precipitation of crystal phases, the composite coating exhibits the lowest corrosion resistance. As the annealing temperature rising to 600°C, the crystalline structure continually grows up and the precipitation transformation tends to be completed. Then the crystal defects decreases which results in an improvement to the corrosion resistance of the composite coating.

Self-Healing Behavior of Pores in Atmosphere Plasma Sprayed Tritium Permeation Barrier Coatings

2010 ◽  
Author(s):  
Jifeng Gao ◽  
Jinping Suo ◽  
Dan Zhang
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Self Healing ◽  
Martensitic Steels ◽  
X Ray Diffraction ◽  
Good Adhesion ◽  
X Ray ◽  
Before And After ◽  
Tritium Permeation ◽  
Plasma Sprayed

Decrease of pores in tritium permeation barriers is one of the most important problems to be addressed for the proper functioning of the fusion reactor. In this paper, a self-healing composite coating composed of TiC+mixture (TiC/Al2O3) +Al2O3 was developed to solve this problem. The coating was deposited on martensitic steels by plasma spraying with a thickness of 100μm. After heat-treatment, the morphology and phase of the coating were investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The corrosion resistance of the coating before and after heat treatment was examined by electrochemistry techniques. The results showed that the TiC+mixture (TiC/Al2O3)+Al2O3 coating exhibited good adhesion to the substrate and a perfect self-healing ability with the porosity decreased by 90% after heat-treatment. The corrosion resistance of the coating increased evidently after the heat treatment. The oxidation/expansion of TiC in the coating played an important role in the sealing of pores.

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