Characterisation of WC-17Co and WC-9Ni HVOF Sprayed Cermet Coatings

2016 ◽  
Vol 840 ◽  
pp. 331-335
Author(s):  
Nur Amira Mohd Rabani ◽  
Zakiah Kamdi
Keyword(s):  
Steel Substrate ◽  
Optical Microscope ◽  
Binder Phase ◽  
High Porosity ◽  
Tungsten Carbides ◽  
Micro Hardness ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hardness Tester ◽  
Vickers Micro Hardness

Cemented tungsten carbides have been paid much attention due its better mechanical properties with excellent combination of hardness and toughness characteristics. The hard WC particles in the coating provide hardness and wear resistance, while the ductile binder such as Co and Ni contribute to toughness and strength. WC-17wt.% Co and WC-9wt.% Ni powders have been sprayed by the HVOF method to form coatings approximately 300μm and 150μm thick onto AISI 1018 steel substrate. Both coatings have been prepared and supplied by an external vendor. The coatings were examined using optical microscope (OM), scanning electron microscope (SEM), and X-Ray diffraction (XRD). The hardness of both coatings were also measured using Vickers micro-hardness tester. The microstructure of the coatings has been analyzed and found to consist of WC, brittle W2C phase, metallic W phase, and amorphous binder phase of Co and Ni. It is found that WC-Ni has a higher hardness value compared to WC-Co due to high porosity distribution.

scholarly journals Nature of Steel Effect on Intermetallic Compounds Obtained by Galvanization

2016 ◽  
Vol 11 (1) ◽  
Keyword(s):  
Intermetallic Compounds ◽  
Steel Substrate ◽  
Optical Microscope ◽  
Atmospheric Conditions ◽  
X Ray Diffraction ◽  
Zinc Bath ◽  
X Ray ◽  
Hardness Tester ◽  
Corrosion Of Steel ◽  
Steel Substrates

Zinc and some of its alloys have a number of characteristics that make it well suited for use as a protective coating against the corrosion of steel substrates under severe atmospheric conditions. The metal of zinc, which represents the main galvanization element offer then a cathodic protection to the ferrous materials. Because of these excellent characteristics, galvanization coatings are expected to be used for different protective applications fields. The objective of this work is to study the influence of the nature of steel substrate on the microstructure and the hardness of the intermetallic compounds. The steels used as the substrate are employed in agriculture field as tubes and irrigation elements in pivot. After an optimal preparation of the surface of the substrate by an appropriate roughness process, the steels specimen were immersed in a molten zinc bath maintained at 450°C. The chemical reactions which take place between the steel and the liquid zinc give rise to the formation of the  and  intermetallic compounds and the -Fe/Zn solid solution. The structure of coating was identified by X ray diffraction. The morphology and thickness of phases formed the coatings at different parameters took place with optical microscope. Finally the hardness of coatings was measured with a Vickers hardness tester.

Effects of NiO Nanoparticles on Physical and Mechanical Properties of BNKT Lead-Free Ceramics

2017 ◽  
Vol 866 ◽  
pp. 282-286 ◽  
Author(s):  
Chatchai Kruea-In ◽  
Suchittra Inthong ◽  
Wilaiwan Leenakul
Keyword(s):  
Mechanical Properties ◽  
Physical And Mechanical Properties ◽  
Micro Hardness ◽  
Nio Nanoparticles ◽  
X Ray Diffraction ◽  
Solid State Reaction Technique ◽  
X Ray ◽  
Hardness Tester ◽  
Lead Free Ceramics ◽  
Vickers Micro Hardness

In this research, The effects of NiO nanoparticles on the physical and mechanical properties of Bi0.5(Na0.81,K0.19)0.5TiO3 (BNKT) were investigated. The ceramics were synthesized by solid state reaction technique. The powder of BNKT was calcined at 850 °C for 4 h. The ceramics of BNKT/x NiO vol.% ( i.e. x= 0.0, 1.0, 2.0 and 3.0) were sintered at 1000-1150 °C for 2 h for optimize condition. Densification, phase formation, microstructure and micro hardness of samples were characterized via Archimedes method, X-ray diffraction techniques (XRD), scanning electron microscope (SEM) and Vickers micro hardness tester. The X-ray diffraction analysis of the ceramics suggests that all samples exhibited a perovskite structure. Densification of samples tended to increase with increasing amount of NiO content with minimun at 1.0 vol.% NiO additive. The NiO additive influenced densification as well as the mechanical properties of the samples. The results of this research suggest that NiO nanoparticles have influence on physical and mechanical properties of BNKT ceramics.

scholarly journals Indentation Creep and Microstructure Properties of Sn-Ag Solder Alloys

2019 ◽  
Vol 16 (1) ◽  
pp. 171-184
Author(s):  
Amal Mohamed Yassin ◽  
B.A. Khalifa ◽  
R. Afify Ismail
Keyword(s):  
Optical Microscope ◽  
Dislocation Motion ◽  
Indentation Creep ◽  
Impression Creep ◽  
Micro Hardness ◽  
X Ray Diffraction ◽  
X Ray ◽  
Microstructure Characteristics ◽  
Controlling Mechanism ◽  
Vickers Micro Hardness

The microstructure and micro-hardness of Sn-3.5wt.5%Ag, Sn-3.5wt.%Ag-0.27wt.%Ti and Sn-3.5wt.%Ag-0.27wt.%Cd treated at 75, 100, 125 and 150oC were studied. The microstructure characteristics of the tested alloys had been investigated using optical microscope (OM), scanning electron microscope (SEM) and x-ray diffraction (XRD). The impression creep had been carried out using Vickers micro-hardness indenter under different loads (10, 50 and 100gm). The stress exponent values were found to be varied from 3.2 to 8.4. The energy activating the creep processes support dislocation climb as the rate controlling mechanism. The dislocation mobility was restricted due to the agglomerations of the Ag3Sn eutectic phase in the above three solders. Whereas; the presence of the twinning of ?-Sn phase, and the dispersion of fine CdSn1.9 IMCs throughout Sn-3.5wt.%Ag-0.27wt.%Cd made strongly blockage of the dislocation motion.

Study on Aging Strengthening of Mg-Zn-Cu Alloy Based on Component Optimization Design

2016 ◽  
Vol 873 ◽  
pp. 33-37
Author(s):  
Jie Ye ◽  
Xiao Ping Lin ◽  
Yun Dong ◽  
Bo Li ◽  
Gao Peng Xu ◽  
...  
Keyword(s):  
Optimization Design ◽  
Optical Microscope ◽  
X Ray Diffraction ◽  
Strengthening Phase ◽  
X Ray ◽  
Hardness Tester ◽  
Cu Alloy ◽  
Factsage Software ◽  
Kinetics Of ◽  
Zn Alloy

In this study, we investigated the aging strengthening of Mg-Zn-Cu alloy based on component optimization design by FactSage software, optical microscope (OM), X-ray diffraction (XRD) and Vickers hardness tester. The results show that the precipitation rate of MgZn2 phase in Mg-6Zn-1Cu is significantly higher than that of the other alloys. When Mg-6Zn-1Cu alloy is subjected to aging at 160<strong>°C</strong> for different time, the phase consists of α-Mg, MgCu2 and MgZn2. The content of main strengthening phase MgZn2 is increasing with the prolonging of aging time. When Mg-6Zn-1Cu alloy aged at 160<strong>°</strong><strong>C</strong> for 10h, the kinetics of precipitation is considerably accelerated. The results indicate that the hardening produced in the Cu-containing alloy is considerably higher than in the Mg-Zn alloy. Therefore, based on component optimization design to establish Mg-Zn-Cu alloy solidification database, and to predict the phase equilibrium and thermodynamic properties of the alloy, is an effective method for the development of new magnesium alloy.

scholarly journals COMPARISON OF SALT BATH PREOXIDATION AND AIR PREOXIDATION FOR SALT BATH NITRIDING

2019 ◽  
Vol 25 (2) ◽  
pp. 130
Author(s):  
Wenchen Mei ◽  
Jiqiang Wu ◽  
Mingyang Dai ◽  
Kunxia Wei ◽  
Jing Hu
Keyword(s):  
Compound Layer ◽  
Salt Bath ◽  
Micro Hardness ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hardness Tester ◽  
Modified Surface ◽  
Salt Bath Nitriding ◽  
Modified Surface Layer

<p class="AMSmaintext1">Salt bath preoxidation was primarily conducted prior to salt bath nitriding, and the effect on salt bath nitriding was compared with that of conventional air preoxidation. Characterization of the modified surface layer was made by means of optical microscopy, scanning electron microscope (SEM), micro-hardness tester and x-ray diffraction (XRD). The results showed that the salt bath preoxidation could significantly enhance the nitriding efficiency. The thickness of compound layer was increased from 13.3μm to 20.8μm by salt bath preoxidation, more than 60% higher than that by conventional air preoxidation under the same salt bath nitriding parameters of 560℃ and 120min. Meanwhile, higher cross-section hardness and thicker effective hardening layer were obtained by salt bath preoxidation, and the enhancement mechanism of salt bath preoxidation was discussed.</p>

scholarly journals Studying the Microstructure of Al-Ti Alloy Prepared by Powder Metallurgy using Three Different Percentages of Ti

2020 ◽  
Vol 26 (6) ◽  
pp. 132-139
Author(s):  
Sahib Mohammed Mahdi ◽  
Nadia Ghadhanfer Hikmat ◽  
Dalmn Yaseen Taha
Keyword(s):  
Electron Microscope ◽  
Powder Metallurgy ◽  
Optical Microscope ◽  
Ti Alloy ◽  
Micro Hardness ◽  
X Ray Diffraction ◽  
X Ray ◽  
Alloy Properties ◽  
Ti Content ◽  
Scanning Electron

The effect of different Ti additions on the microstructure of Al-Ti alloy prepared by powder metallurgy was investigated. A certain amount of Ti (10wt%, 15wt%, and 20wt%) were added to aluminium and the tests like microhardness, density, scanning electron microscope (SEM), optical microscope (OM) and X-Ray Diffraction (XRD) were conducted to determine the influence of different Ti additives on the Al-Ti alloy properties and microstructure. The results show that the grains of α-Al changed from large grains to roughly spherical and then to small rounded grains with increasing Ti content, the micro-hardness of the alloy increases with increasing Ti, and XRD results confirm the formation of TiAl3 intermetallic compound during sintering.

Microstructures and Properties of W-26Re Alloy by SPS

2012 ◽  
Vol 236-237 ◽  
pp. 113-117
Author(s):  
Song Wang ◽  
Ming Xie
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Test Results ◽  
Micro Hardness ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hardness Tester ◽  
Fine Grain ◽  
Plasma Sintering ◽  
Spark Plasma

W-26Re alloy was fabricated by spark plasma sintering (SPS) technology. The phases, microstructures and mechanical properties of the alloy were investigated by X-ray diffraction, optical light microscope, scanning electron microscope, energy dispersion spectroscope, digital display micro-hardness tester and tensile test. Results show that, using SPS technique can prepare W-26Re alloy with high density, fine grain and excellent mechanical properties. The relative density of W-26Re alloy was 96.2%. The main phases in the alloy were determined by the amount of (W) solid solution and the intermetallic  phases. The micro-hardness was 729HV, the ultimate tensile strength was 1680MPa, yield tensile strength was 1143MPa and elongation of alloy was 8.7%.

Materials Development and Hardness Properties of Aluminum Alloy

2014 ◽  
Vol 575 ◽  
pp. 83-87
Author(s):  
Muhammad Husna Al Hasa ◽  
Masrukan ◽  
Arief Sasongko Adhi
Keyword(s):  
Aluminum Alloy ◽  
Rolling Process ◽  
Optical Microscope ◽  
Nuclear Industry ◽  
X Ray Diffraction ◽  
Alloy Plate ◽  
X Ray ◽  
Hardness Tester ◽  
Microstructure Observation ◽  
Rolling Deformation

This research aims to develop an aluminum alloy suitable for applications in the nuclear industry, particularly in terms of its hardness. A synthesized AlFeNiMg alloy plate was subjected to deformation in a gradual rolling process at room temperature. A Vickers hardness tester and an optical microscope were employed to analyze the hardness and to observe the microstructure of the aluminum alloy consecutively. Analyses of elements and phase structures were performed by EDS-SEM and X-ray diffraction. The result shows that the hardness of AlFeNiMg alloy increases along with the increase in rolling deformation. The alloy hardness increases from 88 HV to 113 HV, 135 HV, 153 HV and 165 HV at percent cold reduction of 30%, 53%, 65% and 88% consecutively. From the microstructure observation, the grains tend to get more elongated along with increasing rolling deformation. The pattern analysis of X-ray diffraction shows that there are two phases, namely α and θ (FeAl3).

scholarly journals Mg65Ni20Y15–XAgX (X = 1, 2, 3, 5) alloys prepared via atmosphere controlled induction system

2018 ◽  
Vol 96 (7) ◽  
pp. 810-815 ◽  
Author(s):  
Celal Kursun ◽  
Musa Gogebakan ◽  
Yunus Azakli ◽  
Sezgin Cengiz ◽  
Hasan Eskalen ◽  
...  
Keyword(s):  
Hardness Measurement ◽  
Microstructural Properties ◽  
Micro Hardness ◽  
X Ray Diffraction ◽  
X Ray ◽  
Induction System ◽  
Quantitative Results ◽  
Hardness Values ◽  
Vickers Micro Hardness ◽  
Scanning Electron

In this work, Mg65Ni20Y15–XAgX (X = 1, 2, 3, 5) alloys were manufactured by atmosphere controlled induction system. The effect of Ag ratio on the microstructural properties, micro-hardness, density, and homogeneity of the Mg–Ni–Y alloys were investigated. These alloys were characterized by X-ray diffraction (XRD), optical microscopy, scanning electron microscopy with energy dispersive X-ray (SEM-EDX) and Vickers micro-hardness measurement. According to XRD results, Ni3Y and Mg6Ni phases were observed as well as AgY and Ag17Mg54 phases, which were obtained in alloys. The quantitative results of EDX analysis confirm that the chemical composition of the obtained phases is very close and their homogeneities are so high. The average micro-hardness values of the ingot alloys were measured between 208 and 266 HV for matrix. The elastic modulus and densities of the Mg65Ni20Y15–XAgX (X = 1, 2, 3, 5) alloys increased by increasing Ag in the alloys and they were determined in the range of 58.18–68.12 GPa and 3.14–3.53 g/cm3, respectively.

scholarly journals Yttria stabilized tetragonal zirconia ceramics: preparation, characterization and applicationspplications

2018 ◽  
Vol 53 (2) ◽  
pp. 111-116 ◽  
Author(s):  
N Sultana ◽  
K Bilkis ◽  
R Azad ◽  
MR Qadir ◽  
MA Gafur ◽  
...  
Keyword(s):  
Sintering Temperature ◽  
Tetragonal Zirconia ◽  
Micro Hardness ◽  
X Ray Diffraction ◽  
Zirconia Ceramics ◽  
X Ray ◽  
Hardness Tester ◽  
Maximum Value ◽  
Different Temperatures ◽  
Temperature Water

In this study, yttria stabilized tetragonal zirconia (YSTZ) ceramics were prepared and were sintered at different temperatures to find out the optimum sintering temperature for their better tetragonality and mechanical properties for their application as optical ferrule. Vicker’s hardness was performed by micro hardness tester and it was found to increase with the increase of sintering temperature to a maximum value, then it was decreased with higher sintering temperature. Water absorptivity and porosity were also seen to decrease as the densities of the specimens were increased. X-ray diffraction was employed to determine crystal structure of sintered samples. Surface morphology of the sintered samples was examined through field emission scanning electron microscope.Bangladesh J. Sci. Ind. Res.53(2), 111-116, 2018

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