National Engineering Research Center for Instrument Functional Materials

Chongqing, China

National Engineering Research Center for Instrument Functional Materials

Chongqing, China
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Wang M.,Chongqing Materials Research Institute Co. | Wang M.,National Engineering Research Center for Instrument Functional Materials | Wang M.,Chongqing Key Laboratory of Corrosionresistant Alloys | He W.,Chongqing Materials Research Institute Co. | And 15 more authors.
Gongneng Cailiao/Journal of Functional Materials | Year: 2017

Effect of cold-drawing deformation, solution treatment and ageing treatment on the grain size and mechanical properties of GH4169 wire for nuclear power engineering was studied. It was shown that with a rise in solution treatment temperature, the alloy grain size increased but its hardness decreased. Due to the effect of strain hardening, higher amount of cold deformation resulted in superior room temperature strength, and when the cold drawing deformation is greater than 25%, the contribution of work hardening on tensile strength significantly increased. © 2017, Chongqing Functional Materials Periodical Press Co. Ltd. All right reserved.


Mo Y.,Chongqing Materials Research Institute Co. | Wang D.,Chongqing Materials Research Institute Co. | Wang D.,Chongqing Key Laboratory of Corrosion Resistan Alloys | Wang D.,National Engineering Research Center for Instrument Functional Materials | And 5 more authors.
Jinshu Rechuli/Heat Treatment of Metals | Year: 2017

The solidification structure of 0.066% vanadium (V)-containing 718 alloy ingot was studied by metallurgical microscope (MM), electron probe micro-analysis (EPMA) and energy dispersive spectrum (EDS). The microstructure and precipitated phases characteristics of the two alloys were investigated, as well as distributions and micro-segregations of niobium (Nb). The results are as follows: refined dendritic structure, reduced second dendrite arm spacing and lower segregation coefficient of Nb are observed by the micro-alloying of V. Nb mainly distributes in Laves and carbide precipitated phases, quantitative characterization shows that volume fraction of the two phases can be greatly reduced in 718 alloy with V. The results of linear EPMA-EDS indicate that the further away from Laves phase, the lower Nb content, furthermore, V-containing sample displays slower decreasing trend. All results show that the alloying treatment of V improves micro-segregation of Nb and refines dendritic structure of 718 alloy, which will benefit homogenization heat treatment and composition and microstructure homogeneousness. Particles of V-containing carbides become heterogeneous nucleation centers during solidification process, reduce the driving force of solidification nucleation, which make a narrower second dendrite arm spacing, a lower Laves phase and carbide volume fraction and a finer solidification structure. © 2017, Editorial Office of "Jinshu Rechuli". All right reserved.


Huang G.,Chongqing Materials Research Institute Co. | Huang G.,National Engineering Research Center for Instrument Functional Materials | Huang G.,Chongqing Key Laboratory of Corrosion Resistance Alloys | Tang R.,Chongqing Materials Research Institute Co. | And 10 more authors.
Jinshu Rechuli/Heat Treatment of Metals | Year: 2016

Exploring and drilling devices for high sulfide oil and gas are easy to suffer stress corrosion and stress corrosion cracking (SSC and SCC) due to the influence of medium and temperature and pressure, which requires the metallic materials with excellent mechanical properties and corrosion resistance. Strengthening heat treatment process of a specifically iron-nickel based 3YC61 alloy was investigated. The results show that the best solid solution and 1st aging temperature are 980-1000℃ and 730-770℃ respectively, the properties of 3YC61 steel reaches or exceeds the Incoloy 925 alloy with the 2nd aging treatment of 620℃+620℃×7 h+AQ (the total time of aging treatment is 18 h). The strengthening process can promote the strength, toughness and plasticity of 3YC61 alloy effectively, the comprehensive properties, especially the strength of the 3YC61 alloy after the process are even close to those of Inconel 718 alloy. © 2016, Editorial Office of "Jinshu Rechuli". All right reserved.


Mo Y.,Chongqing Materials Research Institute Co. | Mo Y.,National Engineering Research Center for Instrument Functional Materials | Mo Y.,Chongqing University | Wang D.-Z.,Chongqing Materials Research Institute Co. | And 14 more authors.
Materials Science Forum | Year: 2016

With the application upgrade of alloy 718 in the marine oil exploitation, higher corrosion resistance demands has been presented for structure design and reasonable material application of drilling and production equipments; thus there is an urgent need to understand influences of grain size on corrosion behavior of such alloy in sea water environment. In this experiment, different solution treatments are applied to nickel-based alloy 718. As a result, specimens with grain size varied from ASTM No. 9 to No. 3.5 grades. The influences of grain size on the electrochemical behaviors in simulated sea water (3.5% sodium chloride solution) are investigated using electrochemical impedance spectroscopy and polarization curves. Alloy 718 shows good corrosion resistance in this electrolyte solution, however, grain size still has an effect on its electrochemical corrosion behaviors to a certain extent. With the time going, testing results show that coarse-grained alloys with larger grain size have higher impedance values and smaller corrosion current densities, indicating a better corrosion resistance than fine-grained specimens. However, when the grain size increases further, the corrosivity resistant nature of alloy 718 would decline. Testing results show that specimen with size of ASTM No. 5 has the best corrosion resistance. © 2016 Trans Tech Publications, Switzerland.


Wang C.-G.,Chongqing Instrument Materials Research Institute | Wang C.-G.,Chongqing Key Laboratory of Corrosion Resistan Alloys | Wang D.-Z.,Chongqing Instrument Materials Research Institute | Wang D.-Z.,Chongqing Key Laboratory of Corrosion Resistan Alloys | And 9 more authors.
Materials Science Forum | Year: 2016

To resolve the materials corrosion problems during exploiting high H2S/CO2 oil and gas field, the corrosion behavior of 718 nickel base alloy for 720 hours was studied, the conditions of the experiment is about temperature=177℃, P(H2S)=3.0MPa, P(CO2)=13.5MPa, solution mixed NaCl 20%wt.. The Electronic Parts Manufacturers Association (EPMA) and electrochemical methods was applied to characterize the microstructure, chemical composition and impedance characteristics of corrosion film. The results show that the surface of corrosion film is mainly composition by sulphide of Ni, Cr and Fe, the inside of corrosion film is mainly composition by oxide of Ni, Cr and Fe, electrochemical analysis found the alloy could resist corrosion in this environment. © 2016 Trans Tech Publications, Switzerland.


Hu W.,National Engineering Research Center for Instrument Functional Materials | Hu W.,Chongqing Instrument Materials Research Institute | Xu S.-Q.,Southwest University | Li Q.,Southwest University
Gongneng Cailiao/Journal of Functional Materials | Year: 2010

The formation mechanism, coating structure and growing process of zinc phosphate coating on AZ91D magnesium alloy were studied by means of scanning electron microscopy(SEM), X-ray diffraction(XRD), open circuit potential(OCP). The results show that the growing process of zinc phosphate coating on AZ91D magnesium alloy forming in the phosphating bath process is divided into five stages: the initial nucleation stage(1-5s), the rapid dissolution stage(5-60s), the rapid growth stage(1-2min), steady-state growth stage(2-10min) and the deposition-dissolution equilibrium stage(after 10min). The hopeite phosphate coating on AZ91D magnesium alloy formed in the zinc phosphating bath by batches. The first batch of hopeite nucleus grow into grain gradually, continuous nucleation of new generation occurred simultaneity. The coverage of phosphate grain increased gradually on the alloy surface, the boundary of grain growing closed, and the phosphating process is end until the entire surface is completely covered. With the growth of nucleation and its epitaxial, the phosphate coating formed of on AZ91D magnesium alloy, which is not occured in the metal matrix of the grain boundary with priority.


Yue E.,National Engineering Research Center for Instrument Functional Materials | Yue E.,Chongqing Instrument Materials Research Institute | Tang L.,National Engineering Research Center for Instrument Functional Materials | Tang L.,Chongqing Instrument Materials Research Institute | And 4 more authors.
Gongneng Cailiao/Journal of Functional Materials | Year: 2011

Electroless nickel and nitriding on the surface of iron powder in suspended phase can improve the property of magnetorheological fluid.The antioxidation of iron powder is improved through the electroless nickel and nitriding by SEM, TG, XRD and magnetization characteristic, Fe4N is formed on the surface of iron powder through the nitriding.The wear resistance of magnetorheological fluid is improved through nitriding by friction performance analysis.


Wang M.-B.,Chongqing Materials Research Institute Co. | Wang M.-B.,National Engineering Research Center for Instrument Functional Materials | Ning A.-G.,University of Science and Technology Beijing | Liu H.-D.,Chongqing Materials Research Institute Co. | And 11 more authors.
Materials Science Forum | Year: 2016

The effects of different solid-solution temperature and holding time on the alloy structure and mechanical properties of alloy 718 were investigated. The results show that the grain size grows up as the solid-solution temperature elevates and the holding time prolongs. The grain size increases slowly because undissolved delta phase restrains the growth of grains when solid-solution temperature is below 1000℃, whereas the grain size increases quickly when solid-solution temperature is beyond 1050℃. At room temperature, the strength and hardness of alloy 718 decrease with solution treatment temperature increasing, however, the ductility and toughness of alloy 718 both increase, and the brittle fracture of sample turns into ductile fracture. © 2016 Trans Tech Publications, Switzerland.


Li Y.-Y.,Chongqing Instrument Materials Research Institute | Li Y.-Y.,National Engineering Research Center for Instrument Functional Materials | Wang J.-T.,Chongqing Instrument Materials Research Institute | Wang J.-T.,National Engineering Research Center for Instrument Functional Materials | And 4 more authors.
Gongneng Cailiao/Journal of Functional Materials | Year: 2012

The effect of heat treatment on structure and properties of step-forged shaft were studied.The result indicated, when the heat treatment temperature changed a little, the grain boundaries appeared different microstructure, and influenced the properties of the alloy. In order to meet the requirements of the use of step-orged shaft, using the reasonable heat treatment temperature then. The tensile strength and impact toughness would matched optimally.


Chen L.-X.,National Engineering Research Center for Instrument Functional Materials | Chen L.-X.,Chongqing Instrument Materials Research Institute | Guo W.-F.,National Engineering Research Center for Instrument Functional Materials | Guo W.-F.,Chongqing Instrument Materials Research Institute | And 2 more authors.
Gongneng Cailiao/Journal of Functional Materials | Year: 2011

In this paper, the oxidation of nickel chromium-nickel silicon thermocouple after 605 h aging failure test in the atmosphere in 1200°C was carried out and the oxidation process was analysed, and that the priority oxidation of the Si and Ni in the nickel-silicon alloy is main cause of the tolerance of nickel chromium-nickel silicon thermocouple thermo-electromotive force.

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