共查询到19条相似文献,搜索用时 203 毫秒
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以某钢厂生产的HRB335钢筋和在其基础上加入一定量氮化钛铁的钢筋为原料,通过金相显微镜、扫描电镜、透射电镜等试验方法对氮化钛铁强化钢筋的原理进行研究。结果表明:氮化钛在凝固过程中大量析出,促进了铁素体晶粒的形核,细化了铁素体晶粒,从而起到了提高强度的同时增强韧性的作用;采用萃取复型法得到的析出物主要成分为钛的碳氮化物以及少量的复合氧化物,碳氮化钛的大小通常在10 nm以下,数量多,分布广;由此表明氮化钛铁用来作为生产HRB400热轧带肋钢筋的合金元素具有相当的可行性。 相似文献
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提出了一种测定锰硅合金中氮化钛的方法。试样用硫酸-氢氟酸分解基体,用氢氟酸-过硫酸铵破坏氮化钛,用二安替比啉甲烷光度法测定分离出的氮化钛中的钛。试验了分解基体及氮化钛的试剂、浓度、温度及时间;讨论了不同分离条件对氮化钛提取率的影响;根据氮化钛和碳化钛在不同试剂中的溶解特性,采用分离基体后,先分解碳化钛,再分解氮化钛的分离方法进行了测定,与所拟方法结果一致。通过测定试样中的总氮量及分离氮化钛后的残渣中氮含量进行计算,证明结果可靠。该方法操作简便,对于氮化钛含量小于0.002%的试样,相对标准偏差RSD小于20%。 相似文献
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为改善钛双极板在质子交换膜(PEM)水电解槽环境中的耐腐蚀性能和导电性能,采用电泳沉积-热处理两步法在钛基底表面制备碳掺杂氮化钛(C-TiN)复合保护涂层,并在0.5 mol/L的H2SO4和5 mg/L的F-溶液中模拟PEM水电解槽阳极环境测试其电化学腐蚀性。结果表明,电泳沉积及热处理改善了氮化钛纳米颗粒的连通性,增强了涂层与衬底的粘附力,实现了电子在电活性材料中快速传递。400℃下制备的碳掺杂氮化钛涂层(C-TiN-400℃),其导电性与耐蚀性均得到明显提升;相比于未处理的样品,镀有C-TiN-400℃涂层的样品在146.3 N/cm2压力下的接触电阻可达到2.25 mΩ·cm2。 相似文献
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作者对钒钛烧结矿小高炉冶炼解剖试样,进行了工艺岩石学初探,提出了钒钛烧结矿在炉内还原相变历程图,研究了碳氮化钛生成机理和存在状态以及渣铁形成相变特点。指出了碳氮化钛主要在风口区渣焦接触反应生成,渣铁反应生成碳氮化钛是很次要的。渣中大量碳氮化钛固体微粒和铁珠吸附碳氮化钛包壳导致炉渣性能恶化、渣铁难分。因此,强化喷吹,改革炉型,提高炉缸氧住,消除碳氮化钛影响对强化钒钛矿高炉冶炼是很有意义的。 相似文献
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高炉炉缸内碳氮化钛的生成机理研究 总被引:8,自引:0,他引:8
从热力学和热模拟试验两个方面研究了碳饱和铁浴内碳氮化钛的生成机理。利用CONFOCAL激光高温显微镜的试验数据重新确定了钛在碳饱和铁浴内的溶解度和碳氮化钛形成所需的最低钛含量。结果表明在碳饱和铁浴内生成碳化钛和氮化钛的最低钛含量较采用现行热力学数据计算的结果要低。采用长坩埚法研究了不同温度梯度条件下碳氮化钛的形成,结果发现碳氮化钛在温度梯度较大的耐火材料和铁水界面有团聚行为 相似文献
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采用无标X射线定量分析确定氮化钛粉末材料中诸相的含量。对比了理论K值计算法和无标吸收系数法,指出在工艺研究中无论采用那一种方法自洽性好,对于材料的探索具有相对重要的意义。 相似文献
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罗锡山 《粉末冶金材料科学与工程》1996,(2)
氮化钛由于其一系列固有特性,近年来越来越受到人们的关注,就其特性、应用及制取作一些简单介绍,并报导了作者采用氢化钛粉末通过脱氢-氮化法制取氮化钛的结果。 相似文献
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本文研究了熔液自旋含钛奥氏体不锈钢316L薄带的内氮化行为。试验证明,900℃为最佳氮化温度。细小的氮化物颗粒均匀弥散于基体,阻碍着晶粒长大。通过扫描透射电镜鉴定,颗粒为钛和铬的复杂氮化物。在热处理过程中,颗粒内的大部分铬溶于基体,沉淀相基本为氮化钛。内氮化可使显微硬度明显增加。 相似文献
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《粉末冶金学》2013,56(11):42-58
AbstractCompacts of various metal powders have been prepared and converted to continuous oxide or nitride solids by heating in the appropriate atmosphere. The properties of the materials prepared in this way are described. They were: AIN, Al2O3, Cr2N, Cr2O3, MgO, Si3N4, TiN, and ZnO.Particle size, compact porosity and cohesion, and the reaction-temperature programme all affected the nature of the finished product. The best results were obtained where the metal had a low vapour pressure at the reaction temperature and where the change in molar volume from metal to compound was small. For these reasons, the reaction method is not suitable as a general process but for one of the materials, titanium nitride, it was very successful. This is of special interest since this material is difficult to sinter or hot press. Titanium nitride was made by the reaction method with a voids content of only 13% and a bend strength of 30,000 lb/in2.For a given material, optimum temperatures for the reaction method were low compared with those of conventional manufacturing methods. Special shapes were easily prepared from the parent metal. These advantages may justify the application of the technique to other potentially suitable compounds, which are suggested. 相似文献
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Reaction of Titanium with Boron Nitride under Self-Propagating High-Temperature Synthesis Conditions
We have used the ASTRA computer program for thermodynamic analysis of the chemical reaction of mixtures of titanium with boron nitride in the composition range of 1-26 mass% BN under adiabatic conditions. We have calculated the adiabatic temperatures, the heat change, and the concentration of the reaction products. We have established that under self-propagating high-temperature synthesis (SHS) conditions, we can obtain alloys of titanium with titanium nitride and monoboride and alloys of titanium nitride with titanium borides. Experimental synthesis of the alloys under SHS conditions confirm the thermodynamic analysis results. 相似文献
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Thermodynamics of inclusion formation in Fe-Ti-C-N alloys 总被引:6,自引:0,他引:6
The thermodynamics of the formation of titanium carbonitride in liquid iron-titanium-carbon-nitrogen alloys were investigated
in order to predict under what conditions it will form in liquid steel. A metal-carbonitride equilibration technique was used.
Titanium carbonitride of a desired composition was made by mixing and high-temperature sintering of very fine powders of titanium
nitride and carbide. The formation of titanium carbonitride was confirmed by lattice parameter measurements on the samples
before and after the experiments. The equilibrium concentrations of titanium, carbon, and nitrogen in equilibrium with a specific
titanium carbonitride were obtained at 1873 K. Activities of titanium carbide and nitride relative to pure solid titanium
carbide and nitride were calculated. It was found that titanium carbonitride solid solution is almost ideal. From the results,
calculations were performed to predict at which composition various carbonitrides will form. 相似文献
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磨细高钛高炉渣水化特性研究 总被引:2,自引:1,他引:1
采用X射线衍射、SEM、EMPA、DTA等手段,用对比分析的方法,研究了攀钢磨细高钛高炉渣矿物组成、水化活性、水化产物以及水化过程特征。研究结果表明,攀钢磨细高钛高炉渣水化活性指数仅为77.4%,而普通高炉渣为108%。从水化产物的类型看,高钛高炉渣、普通矿渣、纯水泥三种物质具有相同的水化产物,高钛高炉渣的水化产物数量结晶度明显低于普通高炉渣,从微观结构上说明了攀钢高炉渣水化活性低的原因。 相似文献