Suo Z.Y.,Jilin Institute of Chemical Technology |
Yu B.,Shenyang Research Institute of Foundry |
Qiu K.Q.,Shenyang University of Technology
Materials Science and Engineering A | Year: 2011
Quaternary W30Fe38B32-xCx (x=5, 7, 10, 13, 15at.%) alloys have been investigated by melt-spinning method to produce metallic glasses using low purity industrial raw materials. The phase structure of these ribbons is investigated by X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). The thermal stabilities of W30Fe38B32-xCx (x=5, 7, 10, 13, 15at.%) alloys are analyzed by differential scanning calorimeter (DSC). It is found that W30Fe38B22C10 metallic glass with 45μm in thickness and 2mm width can be successfully fabricated. And other alloys with the same thickness and width as W30Fe38B22C10 alloy are observed with some crystalline peaks on the halo patterns. The DSC measurements show that each alloy undergoes a two-step crystallization with the onset temperature of the first crystallization being as high as 984-1067K. Vickers hardness and density values of W30Fe38B32-xCx (x=7, 10, 13, 15at.%) alloys at room temperature are 11.9-12.8GPa and 14.5g/cm3 at least, respectively. The effect of C addition on GFA in the W-Fe-B alloy system is discussed. © 2010 Elsevier B.V.
Zhang Y.,Shenyang Research Institute of Foundry |
Cui L.-F.,Yantai Products Quality Supervision and Testing Institute
Zhuzao/Foundry | Year: 2016
The brand, chemical component and mechanical property of the heat-resistant steel for general applications (GB/T 8492-2014) and the heat treatment of alloy castings, as well as the characteristics and applications of the standard, were introduced. The comparison of the chemical component of the involved 26 brands in the standard with the ISO standard shows that the domestic standards were mostly based on the international ones, with a slight difference in 1 or 2 elements in few brands. The indoor temperature mechanical properly and the maximum service temperature of the involved 26 brands are set in the standard. The maximum service temperature is suitable only for the comparison among brands. The actual service conditions, such as circumstances, the load, etc., have to be considered in choosing the brand to be used. The proper heat treatment can adjust form, amounts, size, and distribution of the metal strengthening phase, get the right metallographic structure, and gain good comprehensive mechanical properties. © 2016, Chinese Mechanical Engineering Society. All right reserved.
Zhou J.-Y.,Shenyang Research Institute of Foundry
Zhuzao/Foundry | Year: 2012
The sodium silicate inorganic binder is a pollution-free binder of mold and core sand. In recent years, the hardening theory and application practice for sodium silicate bonded sand have made a significant development. The development course of sodium silicate inorganic binder applied to the foundry production over half a century was reviewed briefly in this paper, and the great success achieved in the application of automobile and rolling stock casting was emphatically introduced.
Pan J.-Y.,Shenyang Research Institute of Foundry
Zhuzao/Foundry | Year: 2012
The characters of "quake" and "vibrate" in Chinese scientific literatures were investigated and analyzed. The key words including the two characters were searched respectively, which include vibrating screen, compacting table. The results show that the numbers of the scientific literatures using the two characters are almost equal before 1980; but after 1980 the literatures using the character of "vibrate" increase gradually. Technical personnel prefer using "vibrate" to "quake" in the literatures relevant to mechanical vibration. As tongjia characters, they can interchange in some circumstance, in which they are no correct or mistake. But author think that it is necessary to distinguish the two characters when they were used as scientific term. For example, using "vibration" in the phrase of "mechanical vibration" instead of "quaking"; there is no doubt about using "quake" in the field of earth quake and blast. Questions relevant to the use of "quaking" were put forward about the national standard of "Foundry Terminology". It is more reasonable to use the "vibrate" in the equipments relevant to mechanical vibration, which is in accordance with the result of literatures searching.
Zhang H.,New Northeast Electrical Group High Voltage Switchgear Co. |
Wu H.,Shenyang Research Institute of Foundry
Tezhong Zhuzao Ji Youse Hejin/Special Casting and Nonferrous Alloys | Year: 2014
To improve low pressure casting process for producing pressure-resistant aluminum alloy housing for high voltage switch, core-heart pouring with metallic mould sand core was adopted. Numerical simulation was conducted, and practical production obtained successful effects.
Liu Y.,Northeastern University China |
Wang B.-D.,Northeastern University China |
Bao C.-L.,Shenyang Research Institute of Foundry
Materials Research Innovations | Year: 2015
Subtransus deformation behaviour of Ti-6·5Al-1·5Zr-3·5Mo-0·3Si alloy with a lamellar structure was studied using isothermal hot compression tests under the deformation temperature range 890-995°C and strain rate range 0·01-10 s-1. All of the flow curves exhibited a peak stress at very low strains (around 0·05) followed by considerable flow softening. The TEM results of compressed specimen verified dislocation pile-ups at the α/β interfaces which act as grain boundary strengthening, and calculated flow softening degree by the modified model for grain boundary/interface strengthening developed by Semiatin agreed well with the experimental results. Thus the flow softening can be related to reduction with increasing strain of Hall-Petch strengthening by the α/β interfaces. Then a new constitutive equation was developed for subtransus deformation of Ti-6·5Al-1·5Zr-3·5Mo-0·3Si alloy with lamellar structure by combining the Estrin and Mecking model for strain hardening and an empirical model for flow softening. © W. S. Maney & Son Ltd 2015.
Pan J.-Y.,Shenyang Research Institute of Foundry
Zhuzao/Foundry | Year: 2013
The kinds and research status of the cast grinding balls were presented from the aspects of materials, microstructure of the cast grinding balls. The composition, metallurgical structures, and use characteristics of the cast grinding balls in national and industrial standards were described. Factors influencing grinding media wear, wear mechanism and matrix structure under the wear mechanism were enumerated. Production processes of cast grinding balls in China, sand mold process, metal mold process, and lost foam casting process, etc. were summarized. The opinions on the production and research of grinding balls were put forward.
Zhang Y.,Shenyang Research Institute of Foundry
Zhuzao/Foundry | Year: 2016
This paper introduced the basic composition of microstructure of grey cast iron. The tensile properties of the grey cast iron depend on the morphology and dimension of graphite rather than the matrix. The gray cast iron castings with the same chemical composition have different mechanical properties due to section sensitivity of the castings. The higher strength grades of grey cast iron are achieved with a well formed graphite form resulting from good inoculation, rather than by the introduction of unnecessary alloying elements. Heat treatment is generally applied to enhance material properties. Grey cast irons do not respond well to a heat treatment, because the graphite form principally dictates the properties and any change in the matrix resulting from a heat treatment operation provides little improvement. © 2016, Chinese Mechanical Engineering Society. All right reserved.
Jingyuan Y.,Liaoning University of Technology |
Qiang L.,Liaoning University of Technology |
Ji T.,Shenyang Research Institute of Foundry |
Xudong S.,Northeastern University China
China Foundry | Year: 2011
In present study, BP neural network model was proposed for the prediction of ultimate compressive strength of Al2O3-ZrO2 ceramic foam filter prepared by centrifugal slip casting. The inputs of the BP neural network model were the applied load on the epispastic polystyrene template (F), centrifugal acceleration (v) and sintering temperature (T), while the only output was the ultimate compressive strength (σ). According to the registered BP model, the effects of F, v, T on σ were analyzed. The predicted results agree with the actual data within reasonable experimental error, indicating that the BP model is practically a very useful tool in property prediction and process parameter design of the Al2O3-ZrO2 ceramic foam filter prepared by centrifugal slip casting.
Dong Y.,Northeastern University China |
Jiang Z.,Northeastern University China |
Liu H.,Northeastern University China |
Chen R.,Shenyang Research Institute of Foundry |
Song Z.,Shenyang Research Institute of Foundry
ISIJ International | Year: 2012
Electroslag remelting process will be an important method for manufacturing heavy casing and forging due to its ability to improve the cleanness, macrostructure, microstructure, the distribution and size of non-metallic inclusions. In this paper, a finite element coupling model has been developed based on four electrodes configuration mode for manufacturing large ingot. Maxwell equation, Faraday's law, Navier- Stokes equation, heat transfer equation has been adopted in the model to analyze the current density, Joule-heat density, magnetic induction intensity and electromagnetic force and fluid flow distribution. The impact of slag depth, electrodes immersion depth and filling ratio on the molten pool depth has been analyzed. Results indicated that four electrodes with two sets of bifilar configuration are better than single phase with one electrode type. The molten pool is shallower for four electrodes than conventional single electrode mode, which is in favor of improving large ingot quality. The larger slag pool depth is the shallower the molten pool is. The depth of molten steel pool increases with the increasing of electrode immersion depth under the same slag depth condition. In addition, increasing filling ratio can reduce the depth of molten steel pool, but the filling ratio should be less than 0.6 according to area for general materials. Comparing to the single electrode mode four electrodes configuration mode is in favor of manufacturing large ingot. © 2012 ISIJ.