Hu J.,Northeastern University China |
Du L.-X.,Northeastern University China |
Wang J.-J.,Northeastern University China |
Gao C.-R.,Northeastern University China |
And 3 more authors.
Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science | Year: 2013
Controlled rolling followed by accelerated cooling was carried out in-house to study the microstructure and mechanical properties of a low carbon dual-phase steel. The objective of the study described here was to explore the effect of cooling schedule, such as air cooling temperature and coiling temperature, on the final microstructure and mechanical properties of dual-phase steels. Furthermore, the precipitation behavior and yield ratio are discussed. The study demonstrates that it is possible to obtain tensile strength and elongation of 780 MPa and 22 pct, respectively, at the two cooling schedules investigated. The microstructure consists of 90 pct ferrite and 10 pct martensite when subjected to moderate air cooling and low temperature coiling, such that the yield ratio is a low 0.69. The microstructure consists of 75 pct ferrite and 25 pct granular bainite with a high yield ratio of 0.84 when the steel is directly cooled to the coiling temperature. Compared to the conventional dual-phase steels, the high yield strength is attributed to precipitation hardening induced by nanoscale TiC particles and solid solution strengthening by high Si content. The interphase precipitates form at a suitable ledge mobility, and the row spacing changes with the rate of ferrite transformation. There are different orientations of the rows in the same grain because of the different growth directions of the ferrite grain boundaries, and the interface of the two colonies is devoid of precipitates because of the competitive mechanisms of the two orientations. © 2013 The Minerals, Metals & Materials Society and ASM International.
Zhang B.-G.,Harbin Institute of Technology |
Chen G.-Q.,Harbin Institute of Technology |
Zhang C.-G.,Harbin Institute of Technology |
Ni J.-Q.,AVIC Shenyang Aircraft Corporation
Transactions of Nonferrous Metals Society of China (English Edition) | Year: 2011
Electron beam welding was carried out between aluminum alloy and steel with Ag interlayer. Seam morphology, structure and mechanical properties of the joints were investigated with different action positions of the electron beam spot. The results show that with the increment of the beam offset to the silver side from the interface between silver and steel, the seam morphology was improved, and the porosity in the Ag interlayer vanished. A transition layer mainly composed of Ag 2Al and Al eutectic was formed at the interface between silver and aluminum, and became thin and spiccato as the beam offset increased. When the beam offset was too large, two IMC layers composed of FeAl and FeAl 3 respectively were formed at the interface between steel and Ag interlayer. The optimal beam offset was 0.2 mm, and the maximum tensile strength of the joint was 193 MPa, 88.9 that of the aluminum alloy, and the fracture occurred at the interface between steel and Ag interlayer. © 2011 The Nonferrous Metals Society of China.
Qi Y.M.,Tianjin University |
Qi Y.M.,Tianjin University of Technology and Education |
Zhu X.Z.,AVIC Shenyang Aircraft Corporation |
Deng S.P.,Tianjin University of Technology and Education |
Wang Z.M.,AVIC Shenyang Aircraft Corporation
Applied Mechanics and Materials | Year: 2014
Machine spindle pre-tightening force is closely related to machining precision. Universal spindle is generally pre-tightened through spacer sleeve adjustment. The calculation method about bearing pre-tightening force is put forward through analyzing and computing the main factors of bearing pre-tightening force, and the machine spindle bearing pre-tightening methods based on pre-tightening force are described in detail. This method is used for installation and maintenance of machine spindle, and it is proved to achieve the accuracy recovery of high-revolution, high-precision machine spindle. © (2014) Trans Tech Publications, Switzerland.
Xi J.,Shenyang Aerospace University |
Han Y.,Shenyang Aerospace University |
Su R.,AVIC Shenyang Aircraft Corporation
2013 25th Chinese Control and Decision Conference, CCDC 2013 | Year: 2013
A fault diagnosis approach is proposed for rolling bearing based on the principal component analysis (PCA). Multiple features selected from the time-frequency domain parameters of vibration signals are analyzed. Firstly, by wavelet packet transformation, the wavelet packet energy spectrums of vibration signals are extracted from the different frequency bands. Meanwhile, the time domain statistical features, such as mean value and kurtosis, are also calculated. Then the PCA is used to obtain the best description features from the combination of energy spectrums and statistical features. Finally, a neural network model is established to implement the diagnosis of rolling bearing faults. Practical rolling bearing experiment data is used to verify the effectiveness of the proposed method. © 2013 IEEE.
Fang Z.L.,AVIC Shenyang Aircraft Corporation |
Wu X.J.,Shenyang Aerospace University |
Fang B.X.,AVIC Shenyang Aircraft Corporation
Applied Mechanics and Materials | Year: 2014
Focused on the operation management of equipment, the workflow of NC equipment informatization management was deeply analyzed in this article. The functional structure of equipment management system was studied here. And, the equipment information management system was developed based on B/S structure. The system was applied to manage the basic information, Spare parts and Maintenance of the NC Equipment by way of information and automation, and realize the traceability of equipment maintenance and spare parts management throughout the whole Life Cycle. The alete integration of the Equipment Information Management System and other system, such as DNC, MES and ERP, was realized. And the integrated system effectively promoted the information interaction between layer of enterprise, workshop and equipment. © (2014) Trans Tech Publications, Switzerland.
Zhang H.,AVIC Shenyang Aircraft Corporation |
Guo H.J.,AVIC Shenyang Aircraft Corporation |
Zhang S.S.,Beijing Institute of Technology
Applied Mechanics and Materials | Year: 2014
This paper describes the composition and working principle of aircraft parts flexible automatic assembly platform, and gives the detailed analysis and design of flexible automatic assembly platform of mechanical structure and motion adjusting control system. The two types of multi plane assembly shows that automatic assembly platform automatic adjusting is reliable, operation control system and motion mechanism runs stable, this system can meet the various needs of automatic assembly platform of aircraft components, and it realizes the work mode of assembly and products in one to many during the aircraft components Assembly process. © (2014) Trans Tech Publications, Switzerland.
Lei G.,AVIC Shenyang Aircraft Corporation |
Xiaona L.,AVIC Shenyang Aircraft Corporation
Procedia Engineering | Year: 2015
Some items of an important project are tubes which are made of Titanium alloy. The diameter of the tubes is large but the wall is thin, e.g.Φ25×0.5.The ratio of diameter to wall thickness can reach to 50. At the present time, sorbitol is used to bend this kind of tube. There are some problems need to be resolved, such as long manufacture cycle, insecure bending quality and the difficulty of controlling the quality of the cleaning after bending. The purpose of this paper is to resolve aforesaid problems and find out a kind of new technics substitute for present forming method. © 2015 The Authors.
Geng M.,AVIC Shenyang Aircraft Corporation |
Liu Y.,Shenyang Aerospace University
55th Israel Annual Conference on Aerospace Sciences 2015 | Year: 2015
This paper proposes a novel method with harmonic wavelet packet and Decision-Tree Relevance Vector Machine (DT-RVM). First, calculate the vector energy with wavelet coefficients after the vibration signals have been decomposed with harmonic wavelet packet. The feature vector is prepared after the vector energy is standardized. Second, the multi-classification model is established with the incorporation of three two-classification sub-models in order to diagnose normal state, inner race fault, roller fault and outer race fault. Finally, the proposed model is illustrated with the vibration data from the roller bearing stand of electric engineering lab in American Case Western Reserve University. Experimental results show the proposed model possesses higher accuracy and efficiency compared with conventional Support Vector Machine (SVM) model. Copyright © (2015) by Technion Israel Institute of Technology. All rights reserved.
Wang C.,AVIC Shenyang Aircraft Corporation |
Guo C.,AVIC Shenyang Aircraft Corporation
International Conference on Logistics, Engineering, Management and Computer Science, LEMCS 2014 | Year: 2014
This electronic document is a "live" template. The various components of your paper [title, text, heads, etc.] are already defined on the style sheet, as illustrated by the portions given in this document. DO NOT USE SPECIAL CHARACTERS, SYMBOLS, OR MATH IN YOUR TITLE OR ABSTRACT. © 2014. The authors - Published by Atlantis Press.
Wang X.N.,Soochow University of China |
Sun Q.,AVIC Shenyang Aircraft Corporation |
Du L.X.,Northeastern University China |
Di H.S.,Northeastern University China
Reviews on Advanced Materials Science | Year: 2013
In order to realize the weight reduction of the carriage of heavy-duty truck, the 700 MPa hot-rolled high-strength C-Mn steel plate was successfully developed on 1750 mm hot-strip mills to replace the Q345 steel plate which was originally used for carriage. The microstructure of the plate was composed of fine-grained ferrite, carbides distributed along the ferrite grain boundaries, a little pearlite with 40~50 nm lamellar spacing and a mount of bainite. The yield and tensile strengths of the plate were about 680 MPa and 740 MPa, respectively. The value of n, rm and hole expansion rate (λ) were 0.12, 0.8, and 60%, respectively. The plate has great low temperature impact toughness and weldability. The strengthening mechanisms of the plate were mainly governed by fine-grained strengthening and (Ti,Nb)C nano-precipitates strengthening. If the carriage of heavy-duty truck was constructed by new plate, the weight could reduce 20% due to the thickness reduction. For further reduction of the weight of the carriage, the optimization design was carried out by finite element method. Then, the weight of the carriage could be reduced 12%. © 2013 Advanced Study Center Co. Ltd.