共查询到19条相似文献,搜索用时 500 毫秒
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D型石墨灰铸铁热轧坯模的生产及其应用 总被引:1,自引:0,他引:1
广西大华化工厂铝品分厂轧延车间使用的热轧坯模 ,最大壁厚 5 0mm ,模重 2 90kg ,见图 1。该模主要用以生产热轧坯料 ,最高工作温度 110 0℃ ,生产每件坯料的周期为 3min。图 1 热轧坯模简图 热轧坯模使用的材料多为灰铸铁和蠕墨铸铁。灰铸铁平均使用寿命较低。蠕墨铸铁是热轧坯模理想的材料 ,但其生产成本较高 ,工艺相对复杂。本文介绍D型石墨灰铸铁热轧坯模 ,其生产成本与普通灰铸铁相近 ,比蠕铁每件成本降低 37% ,使用寿命比普通灰铸铁热轧坯模提高 1倍多。D型石墨灰铸铁热轧坯模的化学成分w为 3.90 %~ 4 .2 0 %C ;2 .30 %~ 2 .5… 相似文献
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铁神一号净化剂对灰铸铁组织和力学性能的影响 总被引:4,自引:0,他引:4
利用中频感应电炉熔炼灰铸铁铁液,水玻璃砂造型,浇注铸造阶梯试样、φ30mm试棒以及热分析试样,研究了净化剂对其结晶过冷度、组织和力学性能的影响。试验结果表明,单独加入净化剂0.6%可以增加过冷倾向,细化石墨,降低断面敏感性;可以提高灰铸铁的抗拉强度和冶金质量指标;同时加入净化剂0.6%和硅钡孕育剂0.7%对灰铸铁进行复合孕育,明显增加共晶团数量至441个/cm^2,可以获得细小A型石墨,显著提高灰铸铁的力学性能σb至282MPa。 相似文献
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HAN Qiyong YANG Ping SONG Weixi University of Science Technolonology Beijing Beijing China Division of Metallography Dept.of Materials University of Science Technology Beijing Beijing China 《金属学报(英文版)》1989,2(10):230-234
The distribution of subversive element sulfur in high temperature phases during solidificationof cast iron was investigated by means of liquid quenching method and autoradiography.Theresults show that in grey cast iron,sulfur is concentrated in the liquid,flake graphite and in theperipherial area of D-type supercooled graphite eutectic cells,but less sulfur is in austenite.Besides,the content of sulfur in A-type graphite is higher than that in D-type graphite,andsulfur content in eutectic austenite is a little higher than that in primary austenite.While,innodular graphite cast iron less sulfur is in liquid and austenite,but more in nodular graphite.The blackness of the spots on the emulsion film corresponds to the atomic percentage ofradioactive substances located on the surface of the specimen. 相似文献
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采用水冷金属型铸造,并加入合金元素增大铁液过冷倾向,获得D型石墨铸铁,并用以生产空调器压缩机缸体,其金相组织和性能均达到技术要求。 相似文献
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《International Journal of Cast Metals Research》2013,26(1-4):39-44
AbstractA research programme has been undertaken to achieve a more detailed understanding of graphite nucleation control in grey cast irons, at different sulphur (0˙02–0˙1%), residual aluminium (0˙001–0˙010%) and zirconium (0˙001–0˙015%) levels in iron melts. It was found that three groups of elements are important to sustain a three stage model for the nucleation of graphite in grey irons:(i) strong deoxidising elements (Al, Zr) to promote early formed very small microinclusions, oxide based, which will act as nucleation sites for later formed complex (Mn,X)S compounds(ii) Mn and S to sustain MnS type sulphide formation(iii) inoculating elements (Ca, Sr, etc.) which act in the first stage or/and in the second one of graphite formation, to improve the capability of (Mn,X)S compounds to nucleate graphite.It was confirmed that 0˙07%S level is beneficial for graphite nucleation in grey irons with a lower incidence of carbides and undercooled graphite, compared to 0˙023%S cast irons. Low residual Al level (0˙001–0˙003%) results in higher chill and more undercooled graphite and lower eutectic cell count, in inoculated irons. A 0˙007–0˙010%Al content in the melt is important to sustain type A graphite nucleation and reduced chill. Not only inoculation but also the preconditioning (Al or/and Zr) of the base iron has a strong beneficial effect on the solidification pattern of cast irons. Both Al and Zr sustain the type A graphite formation with a lower degree of undercooling and free carbides. These elements were associated in a complex alloy (FeSi based), very efficient in preconditioning of grey irons for thin wall castings, at a low addition rate. 相似文献
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介绍了不同Ti量对中低CE灰铸铁件组织、力学性能和致密性影响的研究方法。试验结果表明:(1)一定量的Ti增加了铁液的过冷倾向,促进了灰铸铁件D型石墨的形成,湿型砂造型的D型石墨明显多于干型砂。(2)随着铁液中w(Ti)量的增加,中低CE灰铸铁件中D型石墨也不断增加。当D型石墨达到较高比例时,铸件中的厚大热节也大量出现D型石墨,CE较高的铸件力学性能增加;当CE降为3.66%,随着w(Ti)量增加,强度下降幅度较大。(3)随着w(Ti)量的增加,灰铸铁件的致密性下降,缩松几率明显增加。w(Ti)0.17%、w(Al)0.023%时,灰铸件缩松几率为70%。 相似文献