Entity

Time filter

Source Type

Taiyuan, China

Wu R.-R.,Taiyuan University of Science and Technology | Wang R.-F.,Taiyuan University of Science and Technology | Zhao H.-L.,Jinxi Axle Company Ltd
Zhuzao/Foundry | Year: 2013

The basic principle of several kinds of in-situ synthesis technologies and the research status are introduced briefly in this paper, and the characteristics are analyzed and compared, on this basis, the views of the author are offered on the in-situ synthesis technology development direction. Source


Gu J.,Tsinghua University | Liu S.,China Academy of Railway Sciences | Zhou H.,Tsinghua University | Pan T.,Tsinghua University | And 7 more authors.
Zhongguo Tiedao Kexue/China Railway Science | Year: 2014

In order to localize the manufacture of high speed train axle, the influencing factors on the mechanical properties of 25CrMo steel axle billet were experimentally studied. The results show that the composition and cleanliness of 25CrMo steel billet should meet the requirements of EN 13261-2009 standard for EA4T steel and the percentage of alloy elements should be in higher or medium level. Enough forging ratio of axle billet is necessary. A further appropriate heat treatment process with normalizing, quenching and tempering can ensure that the conventional mechanical properties and fatigue properties of the obtained axle billet satisfy the requirement for high speed train axle at the speed of 200~250 km·h-1. The excellent notch fatigue performance is achieved, and the optimal fatigue notch sensitivity coefficient for the sample through the best heat treatment process is 0.16, which is far lower than the maximum allowable value 0.63 in EN 13261-2009 standard. When the grain size of the finished 25CrMo steel axle billet is controlled at level 8 or above, and the microstructure at 1/2 radius of the largest diameter of the axle billet is bainite and tempered martensite (dual phase), the optimal mechanical properties are obtained. Source


Liu J.,Taiyuan University of Science and Technology | Li R.,Jinxi Axle Company Ltd | Fan G.-W.,Taiyuan Iron & Steel Co Ltd Technology Center | Li G.-P.,Taiyuan Iron & Steel Co Ltd Technology Center | And 2 more authors.
Cailiao Rechuli Xuebao/Transactions of Materials and Heat Treatment | Year: 2015

Microstructure evolution of simulated heat affected zone in SAF2507 super duplex stainless steel under different heat input was investigated on a Gleeble3800 thermal-mechanical simulator. Pitting corrosion resistance of HAZ was measured by cyclic potentiodynamic polarization measurements. The results show that austenite content increases from 40% to 52% with the precipitation of intragraular austenite (IGA), grain boundary austenite (GBA) and Widmanstatten austenite (WA) under heat input varing from 0.807 kJ/mm to 2.552 kJ/mm. The PRE value of austenite is larger than that of ferrite at the heat input. Thus, the higher austenite content led to pitting potential increasing from 1030 mV to 1082 mV. However, granular χ phase is observed at the boundary between ferrite and austenite at the heat input of 2.965 kJ/mm reduced the pitting potential to 1065 mV, even though austenite content still increased. ©, 2015, Editorial Office of Transactions of Materials and Heat Treatment. All right reserved. Source


Zhu J.,Tsinghua University | Zhu J.,Control Iron and Steel Research Institute, China | Gu J.,Tsinghua University | Zhou H.,Tsinghua University | And 13 more authors.
Zhongguo Tiedao Kexue/China Railway Science | Year: 2015

In this paper the material selection and manufacture of domestic hollow axle for high speed train have been researched and developed. The route of employing low alloy steels as axle materials and the quenching/tempering treatment process have been adopted based on the investigation of the imported axles from Japan and Europe (Italy and France), national and foreign related standards as well as the survey of equipment and capacity of domestic related manufacturers. We have developed two kinds of low alloy steel hollow axles for high speed train with independent intellectual property, namely, EA4T for 200~250 km·h-1and EA4T plus for 300~350 km·h-1. Both the common mechanical property and fatigue property of the small specimens are superior to those of the imported axles, especially the even more excellent notch fatigue property and low temperature impact property. Moreover, the full-size fatigue tests of EA4T and EA4T plus hollow axles have been approved. Additionally, 30NiCrMoV12 hollow axle for high speed train has been successfully trial-produced and its packaged technology has provided reference for axle selection in the future. ©, 2015, Chinese Academy of Railway Sciences. All right reserved. Source


Kang F.,Jinxi Axle Company Ltd | Wang J.T.,Nanjing University of Science and Technology | Cheng P.,Jinxi Axle Company Ltd | Wu H.Y.,Jinxi Axle Company Ltd
Advanced Materials Research | Year: 2012

Finite element analysis was used to simulate the evolution of damage in a Mg-3Al-1Zn alloy processed by equal channel angular pressing (ECAP). Oyane criterion for damage was selected to evaluate the fracture characteristics. Finite element modeling was used with experimental data obtained from tension and compression testing. The results show that initial crack may form in severe flow localization (i.e. in the inner corner) and these cracks may propagate, leading to billet segmentation. The flow grid in the simulation results is similar to that in the previous experimental results. © (2012) Trans Tech Publications, Switzerland. Source

Discover hidden collaborations