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Zhao X.-S.,General Research Institute for Nonferrous Metals, China | Yuan G.-H.,State Nuclear BAOTI Zirconium Industry Company | Yao M.-Y.,Shanghai University | Yue Q.,State Nuclear BAOTI Zirconium Industry Company | Shen J.-Y.,General Research Institute for Nonferrous Metals, China
Calphad: Computer Coupling of Phase Diagrams and Thermochemistry | Year: 2012

A thermodynamic model of the VZr binary system is established by CALPHAD approach combined with first-principles calculations. The predicted Gibbs free energies of the compound V 2Zr and other end-members in the sublattice model for the V 2Zr phase by the first-principles calculations are used to describe the lattice stabilities of this phase. A set of model parameters for the VZr system is obtained via thermodynamic optimization by using the PARROT module in Thermo-Calc software. The calculated phase diagram agrees well with the reported experimental data. © 2011 Elsevier Ltd. All rights reserved.


Yuan G.,University of Bolton | Zhang L.,CAS Shenyang Institute of Metal Research | Yue Q.,State Nuclear Bao Ti Zirconium Industry Company | Gu H.,CAS Shenyang Institute of Metal Research | And 2 more authors.
Materials Chemistry and Physics | Year: 2015

The β phase precipitates in a Zr-1Nb alloy annealed at 600°C and 700°C (below and above the monotectoid temperature, respectively) for 3h were investigated by transmission electron microscopy. It was found that the uniformly distributed β phase obtained at 600°C was spherical, with diameter of 30-60nm, volume fraction of ~2.5% and Nb content of ~68wt.%. However, the β phase obtained at 700°C was stick-shaped, with ~100nm in diameter and ~300nm in length, volume fraction of ~9.8% and Nb content ~10wt.%. The distinctions in volume fractions and compositions were consistent with the lever rule of the Zr-Nb phase diagram. The distinction in shapes resulted from the change in the interfacial structure, which depended on the lattice misfit. The orientation relationship between α matrix and stick-shape β precipitates satisfied Burgers' orientation relationship, i.e., (101- 0)α//(11- 2)β for the broad face, (0001)α//(110)β for the side facet and (112- 0)α//(1-11)β for the edge. The outline of the stick-shaped β precipitates was composed of straight and curved interfaces, and the broad faces and side facets together formed the straight interface, and the edges formed the curved one. As the Nb content of β phase increased, the lattice misfits on broad face and side facet increased and their interfacial structures changed from coherent (obtained at 700°C) into incoherent (obtained at 600°C), and the misfits of edge decreased, and their interfacial structures were always incoherent for the two heat treatments. Therefore, the curved interfaces had a higher growth rate than the straight interfaces at 700°C and stick-like β phase precipitate was formed. While the three planes have a comparable growth rate at 600°C and spherical β phase precipitate was formed. © 2015 Elsevier B.V.


Yuan G.,University of Bolton | Yuan G.,State Nuclear Bao Ti Zirconium Industry Company | Zhang L.,CAS Shenyang Institute of Metal Research | Yue Q.,State Nuclear Bao Ti Zirconium Industry Company | And 3 more authors.
Materials Chemistry and Physics | Year: 2015

The β phase precipitates in a Zr-1Nb alloy annealed at 600 C and 700 C (below and above the monotectoid temperature, respectively) for 3 h were investigated by transmission electron microscopy. It was found that the uniformly distributed β phase obtained at 600 C was spherical, with diameter of 30-60 nm, volume fraction of ∼2.5% and Nb content of ∼68 wt.%. However, the β phase obtained at 700 C was stick-shaped, with ∼100 nm in diameter and ∼300 nm in length, volume fraction of ∼9.8% and Nb content ∼10 wt.%. The distinctions in volume fractions and compositions were consistent with the lever rule of the Zr-Nb phase diagram. The distinction in shapes resulted from the change in the interfacial structure, which depended on the lattice misfit. The orientation relationship between α matrix and stick-shape β precipitates satisfied Burgers' orientation relationship, i.e., (101¯ 0)α//(11¯ 2)β for the broad face, (0001)α//(110)β for the side facet and (112¯ 0)α//(1¯11)β for the edge. The outline of the stick-shaped β precipitates was composed of straight and curved interfaces, and the broad faces and side facets together formed the straight interface, and the edges formed the curved one. As the Nb content of β phase increased, the lattice misfits on broad face and side facet increased and their interfacial structures changed from coherent (obtained at 700 C) into incoherent (obtained at 600 C), and the misfits of edge decreased, and their interfacial structures were always incoherent for the two heat treatments. Therefore, the curved interfaces had a higher growth rate than the straight interfaces at 700 C and stick-like β phase precipitate was formed. While the three planes have a comparable growth rate at 600 C and spherical β phase precipitate was formed. © 2015 Elsevier B.V. All rights reserved.


Yu J.,State Nuclear BaoTi Zirconium Industry Company | Li X.,State Nuclear BaoTi Zirconium Industry Company | Zhai Y.,State Nuclear BaoTi Zirconium Industry Company | Ren Y.,State Nuclear BaoTi Zirconium Industry Company | Li Y.,China Nuclear Power Engineering Co.
Xiyou Jinshu Cailiao Yu Gongcheng/Rare Metal Materials and Engineering | Year: 2012

Back-Propagation artificial neural network (BP ANN) module with Trainrp algorithm was used to predict annealing parameter and hardness of HANA-4(Zr-1.5Nb-0.4Sn-0.2Fe-0.1Cr) and HANA-6(Zr-1.1Nb-0.05Cu). In this module, chemical compositions, annealing temperature and annealing time were employed as input units while hardness was employed as output unit. The optimal network architecture was considered to be 3-7-1 with momentum factor and learning rate all chosen to be 0.6, respectively. The result of ANN module shows that the biggest relative error (RE) is 7%, and the correlation coefficients (R-value) is 0.98534. The result strongly indicates that the ANN model is an efficient tool to provide annealing parameter. Moreover, Sensitivity analysis (SA) shows that annealing temperature and annealing time are the most important parameters to the ANN model accuracy, the effect of chemical compositions is very small. Copyright © 2012, Northwest Institute for Nonferrous Metal Research. Published by Elsevier BV. All rights reserved.


Yun H.,Chongqing University | Cao-Yong T.,Chongqing University | Ming-Xiang Z.,State nuclear baoti zirconium industry company | Ya-Jie W.,Chongqing University | Yong-Sheng C.,Chongqing University
Advanced Materials Research | Year: 2012

A highly efficient precision grinding method was proposed for the development of Zr-4 alloy used in nuclear industry. The key techniques to develop this new grinding machine are presented in detail, including soft grinding wheel head, ultrasonic thickness measurement system. An automatic polishing and grinding system was built, which is based on ultrasonic thickness measurement technology. According to a lot of grinding experiments, reasonable, accurate and efficient Zr-4 Alloy grinding parameters was determined. The experiments show that when the line speed of belt is about 18 m/s; the workpiece feed rate is 1000mm/min; grinding head cylinder pressure is 0.12Mpa, the silicon carbide abrasive belt of P80 particle size can get 0.02mm grinding amount and achieve excellent grinding effect.The alloy of Zirconium-based added other element has excellent mechanical properties, good workability and weld ability. In the 300 ~ 400°C high temperature and high pressure water and steam, it has good corrosion resistance. Thermal neutron absorption cross section is small and nuclear fuel compatibility is good. Therefore, zirconium alloy is ideal for nuclear reactor core structural material [1-3]. Before entering the cladding tube manufacturing plant, the inner and outer surfaces of the Zr-4 alloy pipe must be processed in order to achieve the required pipe wall thickness and surface roughness. At present, China mainly import diamond deep hole honing technology from the Swedish SUNNEN to grinding the defect of Zr-4 alloy tube's inner surface and finish geometric dimensions.And the inner surface roughness of tube can reach Ra0.32μm. However, this method is limited ability to increase the pipe wall thickness uniformity. The wall thickness of tube mainly depends on mechanical grinding to the outer surface. The grinding of tube wall thickness can ensure uniform wall thickness to provide better conditions for the rolling mill. If a Zirconium tube has non-uniform wall thickness, it would make it hard to reduce the wall thickness tolerances, which is a waste of much metal and increases the burden of metal turning in the rolling process. At present, nuclear power technology in advanced countries such as USA, Japan grinding the wall thickness by mainly using belt grinding. Take Westinghouse for example, the process of grinding the wall thickness is divided into three stages: the manual test of zirconium tube wall thickness distribution; marking the amount and position of grinding; manual grinding according to the mark. In China, the application of abrasive belt grinding technology is a longer history, but the speed of the development is slow [4]. More to the point, China has never been automatic belt grinding machine which is applicable to the nuclear zirconium tube precision and the processing technology and equipments of Zirconium tube have long been dependent on other countries © (2012) Trans Tech Publications, Switzerland.


Yang Y.,Chongqing University | Huang Y.,Chongqing University | Zhang M.,State nuclear baoti zirconium industry company | Wei H.,Chongqing University
Advanced Materials Research | Year: 2012

This paper used BP(Neural Networks) to establish parameter optimization design method for Zr-4 clad tube belt grinding. The BP can get strong nonlinear mapping capability through training, obtain better grinding parameter model; GA(Genetic Algorithm) is not dependent on the specific situation of the problem and it has strong robustness, so it can provides optimization framework for Zr-4 clad tube belt grinding parameter optimization design of nonlinear optimization. This paper optimized the single objective and multi-objective of the abrasive belt life n and grinding roughness Rz, obtained satisfied optimization results and the corresponding grinding conditions © (2012) Trans Tech Publications, Switzerland.


Qiao K.,Xi'an University of Architecture and Technology | Wang W.,Xi'an University of Architecture and Technology | Wu N.,State Nuclear Bao Ti Zirconium Industry Company | Li T.,Xi'an University of Architecture and Technology | Wang K.,Xi'an University of Architecture and Technology
Jinshu Rechuli/Heat Treatment of Metals | Year: 2016

Al/Cu clad plates were joined by friction stir welded (FSW) and the effect of welded speed on mechanical properties and microstructure of nugget zone was investigated. The results show that the distribution of aluminum and copper in weld area presents a laminate character, and the grain size in this zone decreases with the increase of the welded speed. The average microhardness of Cu layer in the nugget zone is 88 HV0.2 accounting for 71.06% of basal metal at the welded speed of 95 mm/min. The average microhardness of the Al layer exceeds the as-received metal to 35 HV0.2 and the tensile strength is 115.22 MPa in the nugget zone when the welded speed is 47.5 mm/min. With the increase of welded speed, tensile strength and elongation decrease, and the fracture surface of tensile specimen is characterized by a cleavage fracture. © 2016, Editorial Office of "Jinshu Rechuli". All right reserved.


Ma L.,State Nuclear Baoti Zirconium Industry Company | Ma L.,Xi'an University of Architecture and Technology | Wang K.,Xi'an University of Architecture and Technology | Yue Q.,State Nuclear Baoti Zirconium Industry Company | Peng S.,State Nuclear Baoti Zirconium Industry Company
Dongli Gongcheng Xuebao/Journal of Chinese Society of Power Engineering | Year: 2014

Taking three typical zirconium alloys Zr-4, M5 and Zirlo respectively in Zr-Sn, Zr-Nb and Zr-Sn-Nb series as objects of study, systematic comparison and analysis were performed to the difference among these alloys in the aspect of second phase particles, mechanical properties, hydride orientation and corrosion resistance, etc., while an evaluation was carried out to their application status. On the basis of current analysis, it is suggested that the material design method should be used in the development of new zirconium alloys with high properties.


Zhang M.,Guangxi University | Ouyang Y.,Guangxi University | Yuan G.,State Nuclear Bao Ti Zirconium Industry Company | Tang Y.,Guangxi University | And 3 more authors.
Xiyou Jinshu Cailiao Yu Gongcheng/Rare Metal Materials and Engineering | Year: 2016

The isothermal section of the Zr-Cr-Cu ternary system at 700℃ was investigated by X-ray diffraction, scanning electron microscope and energy dispersive analysis. The results show that the section is composed of 10 single-phase regions, 18 two-phase regions and 9 three-phase regions. The τ phase occurs as a stable ternary phase at 700℃ when Cr is introduced. No ternary compound is observed in the Zr-rich corner and Cu-rich corner. The alloys in Zr-rich corner consist of ZrCr2, α-Zr and CuZr2, while those in the Cu-rich corner consist of Cr, Cu and Cu5Zr. © 2016, Science Press. All right reserved.


Huang Y.,Chongqing University | Zhang L.,Chongqing University | Huang Z.,Chongqing University | Guo Q.,State Nuclear Bao Ti Zirconium Industry Company
Chongqing Daxue Xuebao/Journal of Chongqing University | Year: 2012

Abrasive belt grinding experiments of Zr-4 nuclear power tube are carried out by using three different abrasive belts with same size, and the interactive generating mechanism between abrasive and workpiece is analyzed, the main factors of material removal rate and surface roughness of Zr-4 alloys are obtained. With the help of the advanced test facilities, the abrasive grain abrasion and surface topography of the workpiece are observed. The metallographic structure and microhardness of the layer of burnt surface during Zr-4 alloys Grinding are analyzed. Some conclusions are given as follows: the material removal rate and surface roughness are mainly affected by the factors of belt speed, grinding pressure, hardness of the contact wheel and abrasive type, of which, the belt speed is the strongest factor. The adhesion wear of the Zirconium corundum and aluminium oxide abrasive grit is more serious, the most important wear form of silicon carbide is abrasion wear. With the onset of grinding burn, the mechanical properties of Zr-4 alloys are deteriorated obviously. The results provide a theoretical and experimental basis for technical optimization in the grinding of Zr-4 alloys with efficiency and high quality.

Loading State Nuclear Bao Ti Zirconium Industry Company collaborators
Loading State Nuclear Bao Ti Zirconium Industry Company collaborators