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1.
原子吸收光度法测定铝合金中锶   总被引:2,自引:0,他引:2  
胡俊勇  徐刚  王平 《江西冶金》2003,23(5):36-37
对铝锶中间合金中锶的测定条件进行探讨,较系统研究了火焰状态、火焰位置、测定体系及干扰元素等对测定结果的影响。  相似文献   

2.
门生会 《冶金分析》2014,34(3):69-82
探讨了用电感耦合等离子体原子发射光谱法(ICP-AES)测定硅铝钡锶合金中锶元素的分析条件并建立了测定方法。样品用盐酸、硝酸和氢氟酸溶解, 硼酸除氟, 试液经过滤后, 选择强度较大、峰形较好、干扰小和稳定性好的421.5 nm谱线作为分析线进行测定。结果表明, 锶浓度在0.001~0.025 mg/mL范围内线性关系良好, 线性方程为I= 11 551.75 ρ+72 706 384, 相关系数R2=0.999 9。对硅铝钡锶合金标准样品进行测定, 锶的测定值与认定值基本一致。硅铝钡锶合金实际样品中锶测定结果的相对标准偏差(n=10)为0.067%, 加标回收率为106%。  相似文献   

3.
本文介绍了锶的用途,并对金属锶的生产方法:铝粉热还原法、熔盐电解法(接触阴极法、Cu—Sr、Sn—Sr、Pb—Sr、Zn—Sr 及 Al—Sr 合金法)进行了评述。  相似文献   

4.
石磊 《铝镁通讯》1999,(3):48-49
本文研究了铅锶合金中铅,锶的测定方法。采用EDTA标准分别滴定铅量和铅锶合量,通过试验找出了最佳条件,具有简便,实用,精密度和准确度高等特点,适用于铅仂中间合金的分析测定。  相似文献   

5.
利用三因子一次正交回归设计导出了铝锶合金在KCl-SrCl_2熔盐体系中的溶解损失的数学表达式,发现铝锶合金中锶在KCl-SrCl_2熔盐体系中的溶解损失随温度、合金中锶含量及熔盐中SrCl_2含量的升高而增大。同时探讨了合金中锶与与其熔盐体系间相互作用的机理。  相似文献   

6.
对现场生产的ZLl01合金铸件材质进行了全面分析,针对存在的产品成分不准,变质效果不好,力学性能不合格的问题,通过改进合金的锶变质工艺和热处理工艺,改善了合金的组织和性能,达到了对材料的成分、性能的各项要求。  相似文献   

7.
研究了成分、锶变质处理和热处理参敌对ZAlSi9Cu4合金组织和性能的影响,得出了镁、锰的合适添加量,锶的最佳添加范围和典型机械性能。  相似文献   

8.
ZA1Si9Cu4的成分,组织与性能研究   总被引:1,自引:0,他引:1  
冷广军 《稀有金属》1995,19(6):405-412
研究了成分、锶变质处理和热处理参数对ZA1Si9Cu4合金组织和性能的影响,得出了镁、锰的合适添加量,锶的最佳添加范围的典型机械性能。  相似文献   

9.
陈瑜 《铝加工》1999,22(3):57-58
近年来,我国一些单位开始应用锶或锶的化合物作为铝-硅合金变质剂,而熔铸过程中要在炉前严格控制锶的加入量,就需快速分析,因此对光电光谱仪增加锶分析方法进行了研究.  相似文献   

10.
锶的分析技术进展   总被引:1,自引:0,他引:1       下载免费PDF全文
综述了近年来国内外锶分析技术的研究和应用状况。对各种检测技术的方法、分析成本、检出限及相对标准偏差等进行了比较,并为测定不同类样品中锶推荐了使用标准。指出了目前测定锶存在的问题,提出了新的发展方向。  相似文献   

11.
研究了火焰原子吸收光谱仪连续测定钨精矿中钡、锶含量的方法。试样经碳酸钠—过氧化钠熔融,熔融物用硝酸溶液提取,在仪器最佳工作条件下,快速、准确地连续测定钨精矿中钡、锶含量。实验表明该方法操作简便,灵敏度高,干扰少,钡的回收率为94.2%~96.3%;锶的回收率为94.0%~102.5%。  相似文献   

12.
The assimilation of cylindrical specimens, manufactured with various proportions of strontium, magnesium, and aluminum, into A356 aluminum alloy melts was investigated. These cylindrical specimens were made as Sr–Mg binary alloys and subsequently as Sr–Mg–Al ternary alloys. Experimental details on the making of these cylinders are presented. A unique melting and casting apparatus was build to melt, mix and cast the reactive metals: strontium and magnesium.Among the various Sr–Mg and Sr–Mg–Al alloys examined the ternary ones, namely 50/25/25 Sr/Mg/Al and 60/20/20 Sr/Mg/Al, exhibited the highest recoveries in the liquid A356 aluminum alloy. In both alloys these high recoveries were observed at 725 °C. The estimated recoveries at this temperature are comparable to that of pure strontium modifier.  相似文献   

13.
The changes in the partial molar thermodynamic characteristics of calcium and strontium in binary dilute alloys with gallium have been measured by the emf method in the temperature range 953–1073 K. The activity coefficients of Ca and Sr indicate a strong interparticle interaction between the alloy components, which increases in going from calcium to strontium.  相似文献   

14.
合成铝酸锶铕绿色荧光粉时,当改变Al/Sr加料比时,产物的物相组成、发光特性和抗水稳定性均有变化。合成产物主要由两相组成,当Al/Sr比为1.5时,合成产物的主晶相为Sr4Al4O2(Al10O23),同时SrAl2O4相的含量也较高。由于SrAl2O4相易于水解,所以其抗水稳定性差。提高Al/Sr比,抗水稳定性逐渐增强。  相似文献   

15.
介绍了真空碳热还原制备Mg-Sr合金新思路,研究了其还原反应的反应式、吉布斯自由能及临界还原温度。结果表明,真空碳热还原MgO,SrO的混合物可以得到Mg-Sr合金;其他因素不变的情况下,还原反应吉布斯自由能随反应温度的提高而减小,随系统气压的降低而减小,随反应生成的Sr,Mg混合蒸气中Sr摩尔分数的减小而减小;反应温度的提高、系统气压的降低和Sr摩尔分数的减小均有利于还原反应的进行;当系统气压为10 Pa,Sr摩尔分数为0.1时,临界反应温度为1353 K;相同系统气压下,碳热还原制备Mg-Sr合金的临界反应温度低于真空碳热炼锶、炼镁的临界温度,反应更易于进行;常规真空硅热还原制备金属镁(皮江法)的反应温度1473 K,气压13.3 Pa下,无论反应生成的Sr,Mg混合蒸气中Mg,Sr相对比例如何,真空碳热还原制备Mg-Sr合金的反应均具备热力学可行性。  相似文献   

16.
The dissolutions of commercial purity strontium and a 90 pct Sr-10 pct Al alloy in liquid aluminum and A356 alloys has been investigated. The dissolutions of these alloys was found to be accompanied by the formation of various intermetallic compounds, the type of which depends on the chemistry and temperature of the melt. Additions at low melt temperatures resulted in the exothermic formation of those intermetallics that have the lowest strontium contents, as seen in the relevant phase diagram,i.e., Al4Sr in liquid aluminum and SrAl2Si2 in liquid A356. Due to low reaction rates at these temperatures, these intermetallics formed as dispersed particles that could easily dissolve in the melt, yielding high recoveries. At high melt temperatures, the associated chemical reactions yielded, as products, the higher strontium intermetallics, which formed with little or no exothermicity. These compounds were observed to be scarcely soluble in the melt, resulting in low recoveries. The dissolution time of these alloys were found to show good agreement with calculated values based on a two-stage model comprising an initial exothermic reaction period and a subsequent free dissolution period. In general, the high-strontium alloys were determined to be efficient at low melt temperatures of 675°C to 700°C. These reactive alloys were observed to form thick surface scales in air, which, in the case of commerical purity strontium, proved to be detrimental to dissolutions because they formed a barrier between the solid and the liquid.  相似文献   

17.
A356合金力学性能的工艺研究   总被引:7,自引:0,他引:7  
叙述了金属锶对A356合金的变质处理,采用复合净化工艺,型腔多点冷却等技术措施,明显提高A356铝合金的力学性能。研究得出一个比较成熟的A356铝合金复杂零件的生产工艺,可供广大材料工作者借鉴。  相似文献   

18.
在电化学工作站AUTOLAB 上采用三电极体系以循环伏安法、计时电流法和计时电位法研究了LiF-SrF2-SrO熔盐体系于1253 K温度下锶在钨电极上的电化学还原过程及其控制步骤.研究结果表明:Sr2+在钨电极上的还原过程是一步得两个电子的准可逆反应,析出电位在-1.0 V 附近.阴极过程受离子的扩散步骤控制,计算得出扩散系数为6.07×10-5 cm2/s.  相似文献   

19.
Automobile and aerospace industries use thin wall aluminium alloy castings which provide lighter structures with excellent mechanical properties. Production of thin wall castings is more challenging due to hot tear formation. Lack of fluidity in molten alloy causes hot tears and must be addressed in thin wall castings of Al-alloys. The present study is focused on a new technique known as stepped ring mould casting. It is possible to assess the hot tear susceptibility of Al–6Zn alloys by varying ring thickness to find out the critical thickness for occurrence of hot tears. The alloy was cast using different strontium (Sr) concentrations (0.2, 0.4, 0.6%). Effects of strontium concentrations were studied in terms of fluidity, porosity content, microstructure and tensile properties of Al–6Zn alloy. In the present work, unmodified and Sr modified alloy casts were characterized by SEM, EDS and XRD respectively. Al–6Zn ingots were procured by master alloy route. Repetition of stepped ring test on the critical thickness showed that hot tear were successfully eliminated significantly due to the addition of Sr. On the other hand, 0.6% Sr also exhibited a good amount of porosity and decrease in elongation. Shorter fluidity length was observed in 0.2% Sr modified alloy. Mechanical and metallographic tests revealed that the alloy castings modified with 0.4% Sr offered better results in yield strength, less porosity and an improved hot tear resistance at micro and macro levels.  相似文献   

20.
针对氯化钙氯化锶混合体系,探索出能够准确分析该体系中钙和锶含量的分析方法。首先,用碳酸盐重量法分别对氯化钙和氯化锶单盐溶液进行分析,能够获得比较准确的测定结果且确定了碳酸盐沉淀适宜的烘干温度和烘干时间分别为200 ℃和20 h。在此基础上,结合碳酸盐重量法和经典的氯化银重量法对氯化钙和氯化锶的混合溶液进行准确地分析,分别获得碳酸盐沉淀的总质量和总氯的物质的量,再通过联立方程组求解得到钙锶氯化物共存体系中各组分的含量。最后,将实验方法用于分析钙和锶物质的量之比YB(YB=nCa∶nSr)为49、9.4、0.98、0.10和0.030的氯化物体系中氯化钙和氯化锶的组分含量时,测定结果比较准确,绝对误差小于0.5%。  相似文献   

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