Phase Formation and Mechanical Properties of Multiphase Carbide Coatings

1999 ◽  
Vol 594 ◽  
Author(s):  
J. E. Krzanowski ◽  
S. H. Koutzaki ◽  
J. Nainaparampil ◽  
J. S. Zabinski

AbstractWe have investigated nano-structured multiphase coatings consisting of mixed carbide components. Two ternary carbide systems, Ti-Mo-C and Ti-Si-C, were examined. Coatings were fabricated by co-sputtering from carbide targets, thereby allowing a complete range of film compositions to be obtained in each system. Films were deposited on Si and sapphire substrates at temperatures ranging from room temperature to 650°C. Film compositions were determined using XPS, and x-ray diffraction and TEM analysis were used to examine the films for texture, grain size, phase stability and the potential for creating nano-structured multiphase films. Mo was found to be soluble in TiC up to about 80% Mo, and between 85–95% Mo a multiphase structure was obtained. The hardness of these films generally did not improve due to the Mo additions. For the Ti-Si-C films, X-ray diffraction results were consistent with the formation of cubic SiC and TiC phases. In these films, the hardness was found to improve with SiC additions optimally giving hardness values of about twice that of TiC alone.

2017 ◽  
Vol 866 ◽  
pp. 199-203
Author(s):  
Chidchanok Chainej ◽  
Suparut Narksitipan ◽  
Nittaya Jaitanong

The aims of this research were study the microstructures and mechanical properties for partial replacement of cement with Fly ash (FA) and kaolin waste (KW). Ordinary Portland cement were partially replaced with FA and KW in the range of 25-35% and 10-25% by weight of cement powder. The kaolin waste was ground for 180 minutes before using. The specimen was packing into an iron mold which sample size of 5×5×5 cm3. Then, the specimens were kept at room temperature for 24 hours and were moist cured in the incubation lime water bath at age of 3 days. After that the specimens were dry cured with plastic wrap at age of 3, 7, 14 and 28 days. After that the compounds were examined by x-ray diffraction patterns (XRD) and the microstructures were examined by scanning electron microscopy (SEM). The compressive strength was then investigated.


2014 ◽  
Vol 622-623 ◽  
pp. 174-178
Author(s):  
Ahmed Ismail Zaky Farahat ◽  
Mohamed Kamal Elfawkhry

Two alloys of steel containing nominally 0.45C-1.0Si-2.0Mn-0.8Al and 1.2Al were cast in open air induction furnace. Dilatation testing was carried out to recognize the effect on Aluminum on the different critically transformation temperatures. The alloys were hot forged at 1200°C and then subjected to different cooling rates. Mechanical testing was carried out at room temperature. Optical and SEM microstructure were observed. X-ray diffraction was conducted to observe the microstructure constituents.


2010 ◽  
Vol 654-656 ◽  
pp. 2126-2129 ◽  
Author(s):  
Yuichi Nakahira ◽  
Tomonari Inamura ◽  
Hiroyasu Kanetaka ◽  
Shuichi Miyazaki ◽  
Hideki Hosoda

Effect of nitrogen (N) addition on mechanical properties of Ti-Cr-Sn alloy was investigated in this study. Ti-7mol%Cr-3mol%Sn was selected and less than 0.5wt% of N were systematically added. The alloys were characterized by optical microscopy, X-ray diffraction analysis and tensile tests at room temperature. The apparent phase was β (bcc) phase, whereas the presence of precipitates was confirmed in 0.5wt%N-added alloy only which did not exhibit sufficient cold workability. The grain size was not largely affected by N addition being less than 0.5wt%. Tensile tests revealed that less than 0.5wt%N addition improves the strength which is due to the solution hardening by interstitial N atoms.


2007 ◽  
Vol 546-549 ◽  
pp. 257-260 ◽  
Author(s):  
Zhen Yan Zhang ◽  
Li Ming Peng ◽  
Xiao Qin Zeng ◽  
Lin Du ◽  
Lan Ma ◽  
...  

Effects of extrusion on mechanical properties and damping capacity of Mg-1.8wt.%Cu -0.5wt.%Mn (MCM1805) alloy have been investigated. Tensile tests and dynamic mechanical analyzer were respectively used to measure tensile properties and damping capacity at room temperature of as-cast and as-extruded MCM1805 alloy. The microstructure was studied using optical microscope, X-ray diffraction and scanning electron microscope with an energy dispersive X-ray spectrometer. Granato-Lücke model was used to explain the influences of extrusion on damping capacity of MCM1805 alloy. The results showed that extrusion dramatically decreases the grain size but has little influence on phase composition and solute atoms concentration of MCM1805 alloy, and the grain refinement was the dominant reason for the obvious increase of tensile properties and decrease of internal friction of MCM1805 alloy.


2013 ◽  
Vol 749 ◽  
pp. 643-647 ◽  
Author(s):  
Lei Li ◽  
Ya Feng Lu ◽  
Wen Xue Li ◽  
Li Ying Zeng ◽  
Yi Yang ◽  
...  

Ti-6Al-4V films were deposited by direct-current magnetron sputtering at different substrate temperatures. The structure and the surface morphology of the films were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The hardness and elastic moduli of Ti-6Al-4V films were measured by nanoindentation test. The results showed that the phase direction of the films deposited at room temperature was (102) orientation, and turned to almost complete (002) preferred orientation at 300°C. For a higher temperature of 500°C, the preferred orientation of the film disappeared and presented a random grain orientation. The hardness and elastic moduli of Ti-6Al-4V films obviously showed the dependence on the temperature. The relationships among temperature, microstructure and mechanical properties of Ti-6Al-4V films were discussed in this paper.


2007 ◽  
Vol 546-549 ◽  
pp. 301-304
Author(s):  
Wei Qiu ◽  
En Hou Han ◽  
Lu Liu

Addition of RE elements to Al-containing Mg alloys can improve properties of Mg alloys at elevated temperatures. In the present investigation, hot-extruded AZ31+x%Nd. (x=0.1,0.3,0.6and1.0 wt%) wrought Mg alloy were prepared .The effects of Nd on microstructures and mechanical properties at room temperature of new alloy were investigated. The investigation found that Nd can bring about two kind of precipitation phases . One is AlNd phase, the other is AlNdMn phase, which were identified as Al11Nd3 and Al8NdMn4 by X-ray diffraction and TEM.


1995 ◽  
Vol 403 ◽  
Author(s):  
Rama B. Inturi ◽  
John A. Barnard

AbstractTiB2, MoSi2, Si3N4 and Ta4N ceramic films were magnetron sputtered on oxidized Si and Coming 7059 glass substrates at ambient temperature. X-ray diffraction studies indicate that the structure of the films is very different on the two substrates, even though the surface of both substrates is amorphous. The hardness and elastic modulii of the films on oxidized Si are slightly higher than those of the films deposited on Coming glass substrate, even at indentation depths where substrate effects are considered to be negligible. A substantial increase in hardness (5–10 GPa) was observed for TiB2 films, when compared to the properties of bulk stoichiometric TiB2. Stress- temperature diagrams determined from room temperature to 250 C indicate that all the films prepared in this study display a pure elastic behavior in that temperature range.


2007 ◽  
Vol 534-536 ◽  
pp. 1077-1080 ◽  
Author(s):  
Junichi Matsushita ◽  
Kenji Shimao ◽  
Yoshiyuki Machida ◽  
Takumi Takao ◽  
Kiyokata Iizumi ◽  
...  

Several boride sintered bodies such as TiB2, ZrB2, and SiB6 were previously reported. In the present study, the sinterability and physical properties of chromium boride (CrB2) containing chromium carbide (Cr3C2) sintered bodies were investigated in order to determine its new advanced material. The samples were sintered at desired temperature for 1 hour in vacuum under a pressure by hot pressing. The relative density of sintered bodies was measured by Archimedes’ method. The relative densities of CrB2 addition of 0, 5, 10, 15 and 20 mass % Cr3C2 composites were 92 to 95 %. The Vickers hardness of the CrB2 with 10 and 15 mass % Cr3C2 composites were about 14 and 15 GPa at room temperature, respectively. The Vickers hardness at high temperature of the CrB2 addition of 10 mass % Cr3C2 composite decreased with increasing measurement temperature. The Vickers hardness at 1273 K of the sample was 6 GPa. The Vickers hardness of CrB2 addition of Cr3C2 composites was higher than monolithic CrB2 sintered body. The powder X-ray diffraction analysis detected CrB and B4C phases in CrB2 containing Cr3C2 composites.


2005 ◽  
Vol 494 ◽  
pp. 211-216 ◽  
Author(s):  
B. Dimčić ◽  
M. Vilotijević ◽  
D. Božić ◽  
D. Rajnović ◽  
M.T. Jovanović

The structural and compression mechanical properties of Ti3Al-based intermetallics produced by powder metallurgy techniques have been studied. The as-milled powders were compacted by hot pressing to non-porous homogenous compacts. Prior to compression tests, all compacts were homogenized by a solution treatment at 1050°C (a+β region) for 1h, followed by water quenching. The compression tests were performed from room temperature to 500°C in vacuum at a strain rate of 1 3 10 4 . 2 − − × s . Detailed microstructural characterization was evaluated by scanning electron microscopy (SEM), followed by energy dispersive spectroscopy (EDS) and X-ray diffraction analysis.


2002 ◽  
Vol 721 ◽  
Author(s):  
P. Kuppusami ◽  
S. Fiechter ◽  
K. Ellmer

AbstractAluminium-doped zinc oxide (ZnO:Al) films have been grown on c-plane (001) and a-plane (110) sapphire by RF magnetron sputtering from a ceramic target. The films grew epitaxially, even at room temperature. However, the crystalline quality depends both on the substrate temperature as well as on the sapphire orientation. The best films, proved by X-ray diffraction (rocking curves and pole figure measurements) were grown on (110)-oriented sapphire in the temperature range 473 to 773 K. The minimum rocking curve half width was about 0.75 °. By Rutherford backscattering analysis it could be shown, that the films exhibit a significant variation of the defect density over the film thickness. The highest density, as expected, is observed at the interface sapphire/ZnO:Al. Films grown on (001)-oriented sapphire have higher rocking curve half widths (about 1.3 °) and exhibit sometimes two types of domains in the same film twisted by 30 °.


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