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1.
《铸造技术》2007,28(7):906-906
一、造型材料 1.砂:石英砂、钙砂、匣钵砂、莫来石砂、刚玉砂、锆英砂、棕刚玉砂、橄榄石砂、陶砂、铝矾土、白云石、电熔石英、石膏、铬铁矿、叶蜡石 2.粘结剂:硬脂酸、合脂、石蜡、硅溶胶、黄糊精、CHC、硅酸乙脂、沥青、耐火泥、氯化镁、硼酸、乌洛托品、氧化铝、修补胶、合箱粘结剂、泥芯膏、脱模剂  相似文献   

2.
国际焊接学会(IIW)会员国家 澳大利亚、意大利、罗马尼亚、奥地利、日本、俄罗斯、比利时、哈萨克斯坦、塞尔维亚、巴西、黎巴嫩、新加坡、保加利亚、利比亚、斯洛伐克、加拿大、立陶宛、斯洛义尼亚、克罗地亚、马来西亚、南非、捷克、墨西哥、西班牙、丹麦、摩洛哥、瑞典、埃及、荷兰、  相似文献   

3.
前言目前各国研制和生产的钛合金中包含有铝、铬、钒、铜、锰、钼、锡、钨、铌、钽、钴、镍、镁、铁、铋、锑、钯、镓、银、钙、硅等二十几个合金元素,铁、硅、氯、硼、磷、氮、氢、氧、碳、铅、锌、钇、砷等十几个杂质元素。它们的含量对钛及钛合  相似文献   

4.
《铸造》2010,(4)
<正>由安微、北京、福建、广东、甘肃、河北、河南、黑龙江、湖北、湖南、江苏、江西、内蒙古、青海、山西、陕西、上海、四川、天津、新疆、浙江及成都、柳州、武汉、西安等地铸造学会主办,由山西  相似文献   

5.
正第19届24省(市、自治区)4市铸造学术会议于2018年8月21~24日在哈尔滨召开。一、会议主题:军民融合、铸造未来二、主办单位安徽、北京、重庆、福建、广东、广西、甘肃、河北、河南、黑龙江、湖北、湖南、江苏、江西、内蒙古、青海、山西、陕西、上海、四川、天津、新疆、云南、浙江等24省(市、区)及成都、柳州、西安、武汉4市铸造学会  相似文献   

6.
一、造型材料1.砂:石英砂、钙砂、匣钵砂、莫来石砂、刚玉砂、锆英砂、棕刚玉砂、橄榄石砂、陶砂、铝矾土、白云石、电熔石英、石膏、铬铁矿、叶蜡石2.粘结剂:硬脂酸、合脂、石蜡、硅溶胶、黄糊精、CHC、硅酸乙脂、沥青、耐火泥、氯化镁、硼酸、乌洛托  相似文献   

7.
《铸造技术》2012,(6):758
由安徽、北京、福建、广东、甘肃、河北、河南、黑龙江、湖北、湖南、江苏、江西、内蒙古、青海、山西、陕西、上海、四川、天津、新疆、浙江及成都、柳州、武汉、西安等铸造学会主办,安徽省铸造学会承办的第13  相似文献   

8.
正第19届24省(市、自治区)4市铸造学术会议于2018年8月21~24日在哈尔滨召开。一、会议主题:军民融合、铸造未来二、主办单位安徽、北京、重庆、福建、广东、广西、甘肃、河北、河南、黑龙江、湖北、湖南、江苏、江西、内蒙古、青海、山西、陕西、上海、四川、天津、新疆、云南、浙江等24省(市、区)及成都、柳州、西安、武汉4市铸造学会三、承办单位黑龙江省机械工程学会铸造专业委员会、哈尔滨工业大学金属精密热加工国家级重点实验室  相似文献   

9.
《中国铸机》2012,(3):62-62
由安徽、北京、福建、广东、甘肃、河北、河南、黑龙江、湖北、湖南、江苏、江西、内蒙古、青海、山西、陕西、上海、四川、天津、新疆、浙江及成都、柳州、武汉、西安等铸造学会主办,  相似文献   

10.
国际标准化组织(ISO)制订的国际标准越来越多地为其成员国所采用,因此,对国际标准中的轻合金牌号及其材料的状态代号作一介绍,是必要的.本文是根据ISO2092-1981(E)及ISO 2107-1983(E)编写的.前者得到下列成员国的批准:奥地利、巴西、中国、加拿大、捷克斯洛伐克、埃及、法国、联帮德国、匈牙利、爱尔兰、日本、朝鲜民主主义人民共和国、南朝鲜、墨西哥、荷兰、挪威、波兰、罗马尼亚、南非、西班牙、瑞典、瑞士、英国、美国、苏联.后者得到下列成员国的批准:澳大利亚、奥地利、加拿大、中国、捷克斯洛伐克、埃及、联帮德国、匈牙利、印度、伊拉克、爱尔兰、意大利、日本、墨西哥、荷兰、尼日利亚、挪威、波兰、沙特阿拉伯、南非、瑞典、瑞士、英国、美国、苏联.  相似文献   

11.
The effect of isochronal heat treatments for 1h on variation of damping, hardness and microstructural change of the magnesium wrought alloy AZ61 was investigated. Damping and hardness behaviour could be attributed to the evolution of precipitation process. The influence of precipitation on damping behaviour was explained in the framework of the dislocation string model of Granato and Lücke.  相似文献   

12.
In view of the periodic bending deformation of solid-liquid interface in the solidification process for continuous casting slab, the variation of temperature gradient and dendritic spacing in the front edge of the solid-liquid interface, and the nucleation and propagation process of crack were studied. It is shown that the bending deformation of the interface results in the temperature field change in the front edge of solid-liquid interface, and the occurrence of temperature gradient along drawing direction results in the growth of secondary dendrites. The initial crack formed during the middle and final stage of solidification may extend to the surface of the casting slab and become an internal crack. The results of the theoretical analysis are basically in agreement with that of the experiment.  相似文献   

13.
Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process.  相似文献   

14.
On the basis of energy and shape method for the determination of the valence bond (VB) structures of crystal, the valence bond structure of titanium is redetermined at room temperature and calculated in the whole temperature range of 0-1943K. The outer shell electronic distribution of Ti is e_c~(2.9907) · (s_c~(0.4980) d_c~(2.4927)) ef1.0093 in crystal. The temperature dependences of the VB structures of hcp and bcc phases are the same. The VB structures of hcp and bcc phases monotonically increase or decrease with the increase in temperature, but show discontinuous changes at the phase-transformation temperature 1155K.  相似文献   

15.
The influence of Fe on the microstructure and mechanical properties of P-doped Ni–Cr–Fe alloys has been investigated.Results showed that increasing Fe content refined the dendrite microstructure and enhanced the solubility of P in as-cast alloys. The change of microhardness in different dendrite regions was attributed to the segregation of P atoms in solid solution state, which had strengthening effects. Increasing Fe contents from 15.2 to 60.7 wt% reduced the yield strength and tensile strength but had little influence on the elongation of alloys. The stress rupture life of alloys after heat treatment decreased with the increment of Fe contents, and the failure fracture modes transferred from transgranular to intergranular fracture mode. The change of fracture modes was due to the weakness of grain boundaries caused by the increment of Fe.In addition, the precipitation of M_(23)C_6 was believed to be related to the segregation of P toward grain boundaries, which led to the fluctuation of carbon and chromium atoms near the grain boundaries in alloys with low Fe contents. Consequently, the increment of Fe decreased the strength of matrix and changed the existence of P atoms and the precipitates at grain boundaries.  相似文献   

16.
本文采用单向减薄制样法在透射电镜下直接观察了20钢渗硼初期硼化物的形核和生长特性及室温形变的影响。X射线及电子探针分析结果表明:渗硼初期试样表层仅有Fe_2B形成;表层硼原子浓度与形变量之间具有单调增长的关系;偏聚于位错胞壁之中的硼原子阻碍了形变组织的恢复和再结晶,加速了硼化物的形核和长大。  相似文献   

17.
Antimony induced crystallization of PVD (physics vapor deposition) amorphous silicon can be observed on sapphire substrates. Very large crystalline regions up to several tens of micrometers can be formed. The Si diffraction patterns of the area of crystallization can be observed with TEM (transmission electron microscopy). Only a few and much smaller crystals of the order of 1μm were formed when the antimony layer was deposited by MBE (molecular beam epitaxy) compared with a layer formed by thermal evaporation. The use of high vacuum is essential in order to observe any Sb induced crystallization at all. In addition it is necessary to take measures to limit the evaporation of the antimony.  相似文献   

18.
The motion of melt droplets in spray degassing process was analyzed theoretically. The height of the treatment tank in spray degassing process could be determined by the results of theoretical calculation of motion of melt droplets. To know whether the melt droplets would solidify during spraying process, the balance temperature of melt droplets was also theoretically analyzed. Then proof experiments for theoretical results about temperature of melt droplets were carried. In comparison, the experimental results were nearly similar to the calculation results.  相似文献   

19.
With the aid of FE (finite element) code MSC.Superform 2005, 2-D coupled thermo-mechanical simulation of center-crack occurrence in round billet during 2-roll rotary rolling process was presented using Oyane ductile fracture criteria. A simple modeling is put forward based on the spiral motion of the workpiece as an essential characteristic in movement. The influence of the feed angle and the entry cone angle of the main roll on the process was taken into account in the modeling. The soundness for simplifying the 3-D rotary rolling into a 2-D problem was discussed. By adopting the parameters of Diescher piercer in 140mm mandrel mill of Bao Steel, the distribution and development of strain / stress were analyzed, and the eigen value of ductile fracture as well. The critical percentage of diameter reduction was obtained from the simulation. The result showed a good agreement with the experimental value, and therefore was of widely guiding significance to the practical process for rationally formulating the deformation parameters of steel tube piercing.  相似文献   

20.
The effect of coloring condition of Al with Calcon (sodium 2,2'‐dihydroxy‐azonaphthalene‐4‐sulfonate), on the corrosion resistance of Al in 0.1 M sulfuric acid solution was studied, using cyclic voltammetry and measurement of impedance noise methods. The changes in the corrosion resistance of colored aluminum electrodes were evaluated by measuring the magnitude of impedance and cyclic voltammetric responses of anodized and colored electrodes. An irreversible corrosion response was observed at the cyclic voltammogram of the colored aluminum electrode. The current and threshold potential of corrosion responses strongly depends on the applied conditions during anodizing, coloring and sealing stages. In addition, significant changes in impedance at the ac voltammogram and noise level at some ac frequencies were observed, when the electrodes were colored under various conditions. In this regard, the surface of the electrode was studied by Scanning Electron Microscopy (SEM). Comparison of SEM images of the colored and uncolored aluminum specimens showed that the colored surface contained a significant numbers of pits. The results indicated that coloring aluminum with Calcon could reduce corrosion resistance of aluminum and increase roughness of the oxide film.  相似文献   

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