scholarly journals Interaction between WC and Inconel 625 under Solid and Liquid State Sintering Conditions

Metals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 666
Author(s):  
Lorena Emanuelli ◽  
Alberto Molinari ◽  
Massimo Pellizzari

Cobalt is the most used metal binder in hard metals since its extraordinary wetting, adhesion and mechanical properties. Nevertheless, it has been recognized genotoxic and cancerogenic with higher toxicity in combination with WC. To substitute Co with an alternative binder, the interaction between the binder and WC must be taken into account. In this work, IN625 is considered as a binder alternative due to its desirable combination of high-temperature strength and corrosion/oxidation resistance. A characterization of the interaction between WC and IN625 was carried out by means of Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectroscopy (EDXS) and X-Ray Diffraction (XRD). Depending on the sintering temperatures, different phases were evidenced at the WC–IN625 superalloy interface. From 1250 °C to 1300 °C, where solid-state sintering takes place, (Cr,Mo)23C6, W2C and (Cr,W) solid solutions were detected. At a sintering temperature of 1350 °C, IN625 melts and the formation of additional phases, such as an intermetallic Ni4W phase and (Mo,W) and (Mo,Nb) solid solutions, were observed. The precipitation of NbC and (Mo,Cr)23C6 carbides in IN625 was also detected.

2012 ◽  
Vol 512-515 ◽  
pp. 1520-1523
Author(s):  
Fann Wei Yang ◽  
Chien Min Cheng ◽  
Kai Huang Chen

In this experimental, solid state method is used to synthesize proportioned nano-ZnO and SiO2 powders into Zn2SiO4 phosphor, and to achieve better control on grain size and grain shape than traditional powder. La is used to replace Mn; and to achieve better control on grain size and grain shape than traditional powder. With different sintering conditions, With different sintering conditions, the effect of the luminescent intensity due to sintering temperature and the concentration of activator would be discussed by the X-Ray Diffraction, SEM and TEM were utilized in the characterization of phase purity and microstructure of phosphor particles. Photoluminescence (PL) spectroscopy was utilized to characterize the optical properties. This use of phosphor materials is the application of the main light source, display components. Therefore, our study zinc silicate as the main principle of doping Mn, La of the characteristics of, expects to find the best glow.


1991 ◽  
Vol 249 ◽  
Author(s):  
C.H. Lin ◽  
T.S. Yan ◽  
T.S. Chin

ABSTRACTBa/Sr titanate powders were obtained by reacting TiO2.xH2O gel in Ba(OH)2 and/or Sr(OH)2 aqueous solution. Different reaction temperatures between 68°C and 98°C and different mole ratios of Ba(OH)2 and Sr(OH)2 were used.X-ray diffraction analysis showed that the titanate powders are cubic, and they are solid solutions of barium and strontium. The lattace spaces of the titanates are affected by the Ba(OH)g/ Sr(OH)g, mole ratio. TEM analysis showed that the titanate powders were spherical, ultrafine, and almost monodispersed. The particle size of the powders is about from 41 to 50 nm depending on the reaction temperature.The titanate powders were compacted and sintered at various temperatures. The best sintering temperature of the powders is about 150°C lower than that of powders made by solid state sintering method.


2014 ◽  
Vol 906 ◽  
pp. 18-24 ◽  
Author(s):  
Bao Lin Zhang ◽  
Bin Bin Zhang ◽  
Ning Ning Wang ◽  
Jing Ming Fei

The effect of milling time and sintering process on the dielectric properties of BaTiO3-based X9R ceramics was investigated. The characterization of the raw powders and the sintered ceramic was carried out by X-ray diffraction and scanning electron microscopy. The particle size distribution of the mixed powders was examined by Laser Particle Size Analyzer. The results shown that with the milling time extended, the Cruie Peak was depressed, or even disappeared. Moreover, with the rise of sintering temperature, the dielectric constant of the ceramics increased and the dielectric loss decreased gradually. Eventually, by milling for 11h and sintering at 1090°Cfor 2h, good dielectric properties were obtained, which were ε25°C≥ 2526, εr/εr25°C≤± 12% (–55~200°C), tanδ≤1.12% (25°C).


2011 ◽  
Vol 04 (03) ◽  
pp. 225-229 ◽  
Author(s):  
WENJUAN WU ◽  
DINGQUAN XIAO ◽  
JIAGANG WU ◽  
JING LI ◽  
JIANGUO ZHU

( K 0.48 Na 0.52) NbO 3-x% Co 2 O 3 (x = 0, 0.03 and 0.05) (KNN-x% Co2O3 ) lead-free piezoelectric ceramics were prepared by the conventional solid-state sintering method. An orthorhombic phase was observed for all KNN-x% Co2O3 ceramics at room temperature, and two phase transitions were confirmed by the high temperature X-ray diffraction and the temperature dependence of the dielectric constant. The Co2O3 greatly improves the density and decreases the sintering temperature of KNN ceramics. The KNN-0.05 mol%Co2O3 ceramic exhibits good properties (d33 = 120 pC/N , k p = 0.41, Q m = 213 and T c = 407°C) and a good age stability. The multiferroic behavior was also observed at room temperature for the KNN-0.05 mol%Co2O3 ceramic, as confirmed by P–E loops and magnetic behavior.


2004 ◽  
Vol 51 (1) ◽  
pp. 59-63 ◽  
Author(s):  
Sanjay K. Rai ◽  
Anish Kumar ◽  
Vani Shankar ◽  
T. Jayakumar ◽  
K. Bhanu Sankara Rao ◽  
...  

1989 ◽  
Vol 03 (05) ◽  
pp. 733-741
Author(s):  
NAROTTAM P. BANSAL ◽  
D. E. FARRELL

In an effort to synthesize the high-T c superconducting phase in the thallium system, two nominal compositions, Tl 2 Ca 2 Ba 2 Cu 3 O 10 and Tl 1 Ca 3 Ba 1 Cu 3 O 8.5, have been investigated for superconductivity as a function of the sintering temperature, time, atmosphere, and quench rate. Samples have been characterized by electrical resistivity measurements, X-ray diffraction, and scanning electron microscopy. Samples of starting composition Tl 2 Ca 2 Ba 2 Cu 3 O 10 fired in air at 860–900°C and rapidly quenched showed T c (R = 0) of 96–107 K. In contrast, specimens of starting composition Tl 1 Ca 0 Ba 1 Cu 3 O 8.5 when baked at 900°C and slow cooled in oxygen were superconducting at ≥ 116 K and consisted of Tl 2 Ca 2 Ba 2 Cu 3 O 10+x as the dominant phase. Our results also show that, in contrast to the case of YBa 2 Cu 3 O 7−x, doping with a small concentration of fluorine sharpens the resistive transition and produces large T c increase in thallium-based superconductors.


1996 ◽  
Vol 11 (4) ◽  
pp. 268-275 ◽  
Author(s):  
Winnie Wong-Ng ◽  
F. Jiang ◽  
Bryan R. Jarabek ◽  
Gregory J. McCarthy

Powder X-ray diffraction was used to investigate the solid solution range of the Bi14SrxCa12−xO33 series in the Bi–Sr–Ca–O system. Solid solution forms over the range 1≤x≤7 in Bi14SrxCa12−xO33. Experimental X-ray reference patterns of selected members with x=1, 3, 5, and 7 have been prepared for the powder diffraction file (PDF). These phases are monoclinic, C2/m, with cell parameter a ranging from 21.473(4) to 21.868(4) Å, b from 4.3564(9) to 4.3898(9) Å, c from 12.753(2) to 12.962(2) Å, β from 102.91(2)° to 102.79(1)°, and V from 1162.9(3) to 1213.5(3) Å3, respectively. These parameters increase monotonically as Ca is continuously replaced by the larger Sr.


2020 ◽  
Vol 12 ◽  
Author(s):  
Zeyang Xue ◽  
Zi Wang ◽  
Chunhu Yu ◽  
Yajing Mao ◽  
Lizhai Pei

Background: Iron tailing causes great environmental and social problems which contaminate water, air and soil. Therefore, it is of important significance to prepare iron tailing ceramsites with microscale pores which can recycle the deposited iron tailing. Objective: The aim of the research is to obtain iron tailing ceramsites with microscale pores and good mechanical performance. Methods: The iron tailing ceramsites have been characterized via scanning electron microscopy (SEM) and X-ray diffraction (XRD). Influence of the content of iron tailing, temperature and duration time on the mechanical performance of the obtained ceramsites was performed and the optimal sintering parameter was determined. The bulk density, apparent density and cylinder compressive strength of the obtained ceramsites increase obviously as improving the iron tailing content, temperature and sintering time. Results: Duration time and sintering temperature play important roles in the formation and size of the pores of the ceramsites. The optimal iron tailing content and sintering parameter are 70wt.%, 1100 ℃ for 40 min. The iron tailing ceramsites mainly consist of orthorhombic CaAl2Si2O8, monoclinic CaSiO3, hexagonal Ca7Si2P2O16, triclinic MgSiO3, triclinic Al2SiO5 and triclinic Ca2Fe2O5 phases. Iron tailing ceramsites from 1100 ℃ for 40 min are composed of irregular particles with several hundreds of micrometers improving the density and strength of the ceramsites. Conclusion: Iron tailing ceramsites containing microscale pores were prepared using iron tailing and fly ash, and exhibit excellent potential for the application in the field of construction.


Open Physics ◽  
2013 ◽  
Vol 11 (2) ◽  
Author(s):  
Aleksandra Mielewczyk-Gryn ◽  
Tomasz Lendze ◽  
Katarzyna Gdula-Kasica ◽  
Piotr Jasinski ◽  
Andrzej Krupa ◽  
...  

AbstractA composite of CaTi0.9Fe0.1O3 and electrolyte material, i.e. magnesium doped La0.98Mg0.02NbO4 was prepared and studied. The phase content and the sample microstructure was examined by an X-ray diffraction method and scanning electron microscopy. EDS measurements were done both for composite samples and the diffusion couple. The electrical properties were studied by four terminal DC method. The high-temperature interaction between the two components of the composite has been observed. It has been suggested that lanthanum diffused into the perovskite phase and substituted for calcium whereas calcium and niobium formed the Ca2Nb2O7 pyrochlore phase. At 1500°C very large crystallites of the pyrochlore were observed. Regardless of strong interaction between the composite components, its total conductivity was weakly dependent on the sintering temperature.


2013 ◽  
Vol 49 (3) ◽  
pp. 296-302 ◽  
Author(s):  
A. A. Bush ◽  
V. Ya. Shkuratov ◽  
K. E. Kamentsev ◽  
V. M. Cherepanov

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