In的添加对Sn-9Zn无铅焊料合金组织与性能的影响

锡锌（Sn-Zn）无铅焊料在电子封装中具有广阔的应用前景,但其润湿性和抗氧化性能较差。采用16通道摇摆炉制备Sn-9Zn-x In(x=0,1,2,3,4;%,质量分数)焊料合金,研究In元素对Sn-9Zn无铅焊料合金微观组织、熔化特性、润湿性、抗氧化性以及力学性能的影响。结果表明：添加的In元素与Sn,Zn形成低熔点合金,明显降低焊料合金的熔点及固相线温度;加入In元素使得焊料合金表面张力降低,润湿性能提高;焊料合金的润湿力在In含量为3%达到最大值（0.857 mN）;焊料添加In元素形成In2O3氧化膜有保护熔体的作用,有助于增强焊料合金抗氧化性能,不含In元素时焊料合金的氧化增重为0.47%,而In含量为3%时其氧化增重质量分数为0.14%,抗氧化性能提高;添加In后在Sn基体中产生固溶强化和析出强化使得合金抗拉强度先提高后降低,当In含量为3%时,焊料合金极限抗拉强度达到55 MPa左右。加入In后破碎为长条状、针棒状的富Zn相使得延伸率逐渐下降,当In添加量大于3%时,延伸率急剧下降。综合焊料的力学性能、润湿性、抗氧化性能,确定In的在Sn-9Zn中最优添加量为3%。     

Sn-Zn系无铅钎焊料的发展现状与展望

阐述了无铅焊料的发展过程,对Sn-Zn系无铅焊料发展现状及研究进行了介绍.详细分析了一些合金元素添加后对Sn-Zn系钎焊料的影响,同时叙述了对Sn-Zn焊料与Cu、Al、Ni材质基板之间的界面反应研究,并对Sn-Zn系钎焊料的研究及商业化应用进行了论述和展望.     

微量稀土元素对Sn57Bi1Ag焊料合金组织与性能的影响

研究微量稀土元素对Sn57Bi1Ag无铅焊料合金显微组织以及性能的影响。结果表明,当稀土含量为0.05%～0.5%(质量分数)时,对该无铅焊料合金的导电性和腐蚀性影响不大,但使熔化区间温度降低;可以提高焊料合金的力学性能,提高焊料的铺展面积,细化组织。比较Ce、Er、Y三种稀土元素对焊料合金的影响,发现Er元素可以更好地提高焊料合金的综合性能,Ce次之。     

Sn—Ag基无铅焊料的研究与进展

研究开发无铅焊料是我国电子材料行业面临的新课题,Sn-Ag系是一种有希望替代铅焊料的无铅焊料。本文综述了该合金系研究的主要成果,包括微观组织、焊料与基体的相互作用、拉伸和剪切性能、疲劳性能及蠕变性能,指出了此合金系作为软钎焊材料尚待解决的问题。采用合金化、基体涂层、发展新焊剂等手段可使该合金系发展为较理想的无铅焊料。     

微量稀土元素对Sn57BilAg焊料合金组织与性能的影响

研究微量稀土元素对Sn57Bil Ag无铅焊料合金显微组织以及性能的影响.结果表明,当稀土含量为0.05％ ～0.5％(质量分数)时,对该无铅焊料合金的导电性和腐蚀性影响不大,但使熔化区间温度降低;可以提高焊料合金的力学性能,提高焊料的铺展面积,细化组织.比较Ce、Er、Y三种稀土元素对焊料合金的影响,发现Er元素可以更好地提高焊料合金的综合性能,Ce次之.     

Sn-Bi-In合金焊料及相图计算基础

Sn-Pb软钎焊料由于润湿性好、性能优良,是电子封装领域主要运用的传统软钎焊材。Pb有毒不符合绿色发展的理念,减少Pb的使用能保护环境和人体健康,必须研发新型无铅焊料替代传统的Sn-Pb焊料。新型的低温软钎焊料包括Sn-Bi, Sn-In两系合金。本文总结了Sn-Pb焊料的优点和缺点,与Sn-Pb焊料相比较阐述了Sn-Bi, Sn-In系低温无铅焊料的性能。分析了In, Bi的相互作用对锡基无铅焊料组织及性能的影响。低温的Sn-Bi-In系合金绿色无污染,将是一种能够运用于消费电子产品的新型无铅焊料合金。通过相图计算可以筛选较优的合金成分,为Sn-Bi-In无铅焊料的设计和性能研究提供参考,因此Sn-Bi-In三元系相图的计算尤为重要。文章中论述了Sn-Bi-In系合金的相图计算研究现状及热力学模型,收集整理了一些Sn-Bi-In三元合金的相结构参数和热力学数据,同时结合了CALPHAD说明了将相图计算运用于新型Sn-Bi-In焊料开发的优势。     

Sn—Zn—Al焊料合金的微观结构

使用扫描电子显微技术研究了无铅焊料Ｓｎ－Ｚｎ－Ａｌ的微观结构。在所研究的焊料中,Ａｌ和Ｚｎ的成分分别是在０．４５￣４．５％和８．５５￣８５．５％范围内。焊料由Ｚｎ－５Ａｌ母合金和金属Ｓｎ制备。并用能量散射光谱仪对在这些焊料中形成的析出物作成分分析。用冷却曲线和示差扫描量热法标出了在冷却过程中这些焊料的共晶温度和转变温度。     

SnX_yCu1.5Ni系无铅焊料耐蚀性能研究

采用人工模拟助焊剂介质的储存环境和盐雾腐蚀两种的方法研究了Sn-X-Cu-Ni系列无铅焊料腐蚀性能,结果表明,SnXyCu1.5Ni系列焊料中Sn-X4.5-Cu1.5-Ni合金的耐蚀性能最佳,合金发生局部性腐蚀为主,当y≥5时,焊料的耐蚀性能随着y的增加而变差。     

微量元素对SnAgCu无铅焊料润湿性的影响

以Sn0.1Ag0.7Cu为基体合金,在此基础上分别添加微量元素Ni, Ge, Ce。采用焊料合金铺展性实验法和润湿平衡法测试焊料合金的铺展率、铺展面积、润湿角、最大润湿力、润湿时间以及表面张力。探讨添加不同含量的微量元素Ni, Ge, Ce对Sn0.1Ag0.7Cu焊料合金润湿性的影响。实验结果表明:添加Ni能较大提高Sn0.1Ag0.7Cu焊料合金的润湿性能, Ni含量为0.03%时焊料润湿性最佳,润湿时间为0.6488 s,最大润湿力为1.0129 mN,铺展率为76.2%;添加Ge对Sn0.1Ag0.7Cu润湿力影响最大,随着Ge含量的增加,润湿力呈持续下降趋势,但是适量的Ge对焊料的铺展性的改善也是很明显的,当Ge含量为0.03%时,铺展率最大,此时焊料合金的铺展率为75.9%,铺展面积为72.8 mm~2,润湿角为24.2°,表面张力为0.39 mN·mm~(-1);当Ce元素含量为0.05%时,焊料合金润湿性最好,此时铺展率为76.2%,铺展面积为73.2 mm~2,润湿角为23.8°。     

SnCu0.7无铅焊料抗氧化性能研究

无铅焊料抗氧化性能差已经成为钎焊行业的共性问题。以SnCu0.7无铅焊料为研究对象,向钎料中添加微量元素P和Ge改善其抗氧化性能,并采用模拟波峰焊进行动态氧化渣渣率测试。试验结果表明:当SnCu0.7无铅焊料中添加100 ug/g的P元素时,其动态氧化渣渣率为0.409%,连续波峰测试抗氧化失效时间为56～64 h。SnCu0.7无铅焊料中添加P与Ge相比较,前者的抗氧化性能更优,而且成本更低。     

The Behaviour of Selenium Impurities During the Addition of Se‐Containing Manganese to Steel Melt

Manganese is an important alloy addition for alloy steels. It is normally added to steel melts as ferromanganese. However, for the adjustment of melt composition, manganese metal is used as a trimming addition since it has lower levels of impurities than ferromanganese. The manganese used for this purpose is obtained from the electrolytic processing route wherein selenium‐containing additives are added to the electrolyte bath to improve the current efficiency. This practice introduces selenium to the manganese metal. Given that selenium and its compounds are potentially toxic and damaging to the work place and environment, effluents have to be treated in a controlled manner. In order to determine how selenium typically distributes between molten steel, slag and gas phases, a laboratory‐scale experimental study was carried out to evaluate the deportment of selenium following the addition of selenium containing manganese to the steel melt. Contaminated commercial manganese metal, as well as Mn‐Al‐Se spiked briquettes with different selenium contents were added to steel melts at 1600 °C. Selenium recovery to the solidified steel samples varied from 16% to 75%, depending on selenium levels of additions. Owing to the high vapour pressure of selenium, significant amounts of the selenium added to the melt evaporated, reacting with air to form selenium dioxide. SEM analysis of the solidified steel samples revealed that the selenium was largely present as manganese selenide (MnSe) in the form of spherical inclusions within the iron matrix. A thermodynamic assessment on the potential formation of possible selenium compounds within the steel melt suggests that the most stable selenium compound under the test conditions is MnSe, in accord with experiments.     

铅基合金中硒的测定——高锰酸钾容量法

高锰酸钾法测定铅基合金中的硒含量。试样用硝酸溶解，在硫酸介质中，加入过量的高锰酸钾，将亚硒酸氧化为硒酸，然后加入过量的硫酸亚铁按标准溶液还原过量的高锰酸钾，最后用高锰酸钾标准溶液滴定过量铁（Ⅱ）。     

饮用水管件用铜合金的研究

为了解决因铋的加入引起的铜合金脆化问题，研究结果表明，通过添加元素Sn、P完全解决了因铋引起的脆化问题，并提出了配方Cu-BilSn3Zn6P0.03。     

Selenium regulation of classical glutathione peroxidase expression requires the 3' untranslated region in Chinese hamster ovary cells

Classical glutathione peroxidase (GPX) mRNA levels fall dramatically in selenium (Se)-deficient animals, but it is not known whether this mechanism is related to the mRNA 3' untranslated region (3'UTR) sequences that have been shown to direct Se incorporation. In this study, we used recombinant GPX constructs to investigate the role of the GPX 3'UTR in Se regulation of GPX mRNA levels in Chinese hamster ovary (CHO) cells. The CHO cells were transfected with GPX (pRc/GPX), GPX lacking the 3'UTR (pRc/Delta3'UTR) or the pRc/CMV vector alone, and GPX activity and GPX mRNA levels were determined in stable transfectants grown in low Se basal medium with a range of added Se concentrations. We identified two pRc/GPX transfectants with significantly elevated GPX activity levels compared with pRc/CMV transfectants. The elevated GPX expression did not dramatically shift the amount of Se that was sufficient for GPX activity to reach the Se-adequate plateau level (100 nmol/L added Se). As expected, GPX activity was not significantly different when pRc/Delta3'UTR transfectants were compared with pRc/CMV control transfectants. Among the wild type and transfected CHO cells, Se-deficient GPX activity levels averaged 35 +/- 5% of Se-adequate levels. Selenium-deficient levels of endogenous GPX mRNA as well as recombinant pRc/GPX mRNA averaged 54-58% of Se-adequate levels; 3-4 nmol/L added Se was sufficient for maximal GPX mRNA levels. In contrast, pRc/Delta3'UTR mRNA levels in the unsupplemented cells remained at Se-adequate levels and showed no distinct Se regulation. These studies demonstrate that the GPX 3'UTR is necessary for Se regulation of GPX mRNA levels in addition to its role in Se incorporation.     

电感耦合等离子体原子发射光谱法测定铅锑合金中12种元素

采用硝酸分解样品,柠檬酸抑制Sb水解,全谱直读电感耦合等离子体发射光谱仪同时测定铅锑合金样品中常量的Sb、次量和微量的As、Cu、Sn、Se、Ag、Bi、Fe、Zn、Ni、Cd 、Mn等12种元素。筛选了不同溶样方法和仪器参数,在优选条件下,测得方法检出限如下：Sn、Ag和Fe为0. 01 μg/g,Mn为0.02 μg/g,Bi和Cd为0.03 μg/g,Sb、As和Zn为0.04 μg/g,Se和Ni为0.05 μg/g,Cu为0.08 μg/g。基体铅对测定产生背景干扰,但可以通过硫酸铅沉淀除去。方法用于铅锑合金样品中上述12种元素的测定,结果与原子荧光光谱法或原子吸收光谱法相符,相对标准偏差（RSD,n=11）为0.87%~3.8%,加标回收率在95.2%~107.4%之间。     

Influence of Rare Earths on the Directional Solidification Microstructure of Tin-Lead Eutectic Alloy

ＩｎｆｌｕｅｎｃｅｏｆＲａｒｅＥａｒｔｈｓｏｎｔｈｅＤｉｒｅｃｔｉｏｎａｌＳｏｌｉｄｉｆｉｃａｔｉｏｎＭｉｃｒｏｓｔｒｕｃｔｕｒｅｏｆＴｉｎＬｅａｄＥｕｔｅｃｔｉｃＡｌｏｙＺｈｕＹｉｎｇ（朱颖），ＦａｎｇＨｏｎｇｙｕａｎ（方洪渊），ＱｉａｎＹｉｙｕ...     

Cu-9.5Ni-2.3Sn-0.25Si合金铸态组织与时效性能的研究(续)

图4为Cu-9．5Ni-2．3Sn-0．25Si合金经400~C×4h时效后微观组织与扫描电镜照片。由图4（a）中可以看出：合金经70％的冷变形时效后,合金晶粒组织明显破碎,并有大量的第二相小颗粒析出,而且分布均匀。     

环保型镁钎料合金的研究

试验研究了Sn对环保型镁锌合金钎料焊接拉伸性能的影响.拉伸实验表明,镁合金中加入Sn后,接头的强度大大提高.锡含量过高强度又降低.锡造成合金强度下降的原因是镁锡脆性化合物增多.     

砷共沉淀-电感耦合等离子体原子发射光谱法测定金精矿中硒和碲

采用硝酸-盐酸-高氯酸分解样品,以2.0 mL 1.0 mg/mL砷溶液作为聚集剂,滴加250 g/L氯化亚锡溶液和加入次亚磷酸钠(固体)作为还原剂,将溶液中硒、碲、砷还原成单质而共沉淀,再用硝酸-高氯酸溶解过滤后的沉淀,选择Se 196.090{171} nm和Te 214.281{157} nm为分析线,建立了电感耦合等离子体原子发射光谱法(ICP-AES)测定金精矿样品中砷和碲的方法。实验表明:砷共沉淀法可将硒、碲与样品中大部分干扰元素(银、铅、锌、硅、钙、镁、铝和铁等)分离,避免了基体的干扰;虽然金精矿中的金在共沉淀的过程中会被还原而部分析出,但干扰试验表明,与硒、碲元素同时从基体溶液中分离出来的金对测定的干扰可忽略。在选定的实验条件下,硒和碲的质量浓度在0.5～2.0 μg/mL范围内与其发射强度呈良好的线性关系,硒、碲校准曲线的线性相关系数(r)分别为0.999 2和0.999 1;方法中硒和碲的检出限分别为1.40和4.23 μg/g。按照实验方法测定金精矿实际样品中硒和碲,结果与分光光度法的测定值相吻合,相对标准偏差(RSD,n=8)分别为2.0%～2.4%和3.1%～3.3%。     

Evaluation of the behavior of selenium in silicate slag

The solubility of Se in silica saturated iron silicate slag was examined at 1458 and 1523 K using a static distribution technique. The procedure involved equilibrating slag with a molten Cu-Se alloy. The final Se content of both the slag and metal phases was determined using hydride generation in conjunction with atomic absorption. The slag specimens were also analyzed for their ferrous and ferric ion content. The results of this investigation indicate that the solubility of selenium in slag increases as the Fe²⁺/Fe³⁺ ratio increases, and that the solubility is constant at lower values of that ratio. These results are consistent with the model proposed by Nagamoriet al. ^1,2 In that study selenium is postulated to exist in both a neutral state and as an Fe-Se complex. In this work a method is presented whereby one can evaluate the nature of Fe-Se complexes. Analysis of the data obtained in this study, and the data obtained by Nagamori and co-workers, suggests that the Fe-Se complex has an Fe/Se ratio of approximately 1∶2. This study also presents a method, for calculating the fraction of neutral selenium present in slag.