新型碱性锌酸盐镀锌工艺对锌阳极板的要求

针对高分散性能的新型碱性锌酸盐镀锌工艺中形状复杂零件朝上的内腔和低电流密度区镀层严重粗糙、发黑的现象,通过分析故障现象、阳极产物属性、来源、产生机理,确定阳极上的黑色产物为Fe,源于Zn锭在普通碳钢锌锅中熔铸时因高温扩散,因此确定采用低碳痕Si型钢板制作锌锅、控制熔锌温度至450～460 ℃,用耐强碱滤布包覆阳极等方式进行电镀,从而保证了新工艺的正常运转.     

碱性锌酸盐镀锌添加剂的研究

研制了一种高性能环保型碱性锌酸盐镀锌添加剂CZ,采用电化学测试、扫描电镜分析及EDAX能谱分析等手段进行了镀层性能检测,并将其与传统添加剂性能进行了比较.结果表明,该添加剂具有光亮电流范围广、分散能力佳、深镀能力好等优点,所得镀层脆性低,二次加工性好.     

高速电镀锌用不溶性阳极

综述了高速电镀锌用不溶性阳极的组成和性质，介绍了阳极预处理的方法以及镀液中存在的其他离子对阳极破损速率的影响，并对有关阳极破损的机理进行了探讨。     

耐高温碱性锌酸盐镀锌光亮剂的应用

介绍了碱性锌酸盐环保镀锌的新工艺，对镀液，镀层性能等进行了试验及生产实践，可见该光亮剂能使碱性锌酸盐镀锌工艺得到改善，表现为耐高温，出光快，结晶细，镀层光亮，均，深镀能力好，能抑制气雾等，它还解决了碱性锌酸盐镀锌在60℃高温时，不能正常生产的技术难题。     

一次氰化镀锌故障排除的启示

某产品零件在氰化镀锌溶液中电沉积锌出槽后,锌镀层发暗,有黑斑,经硝酸溶液浸渍出光,锌镀层严重发暗,且有暗色斑点,无论是硝酸出光,还是低铬酸出光,表面均呈黑褐色,零件孔眼部位呈亮白色,钝化后严重发雾,钝化膜无光泽且发喑。仔细观察电镀过程,发现锌阳极板阳极区内出现微量丝状黄色絮状物,阳极溶解异常,经过判断黄色絮状物是Cd与镀液中的S反应生成硫化镉黄色沉淀。原来操作人员误将镉板当做锌阳极使用,造成本次故障的发生。     

锌酸盐镀锌在纺机摇架上的应用

介绍了BZN-99型锌酸盐镀锌在纺机摇架上的应用，并详细叙述了BZN-99光亮剂的性能及优缺点。BZN-99与原DPE—Ⅲ型镀液相比，具有镀层外观光亮，耐蚀性、韧性好，镀液维护简单等特点。     

电镀锌故障排除一则

我厂1993年开始采用氯化物镀锌工艺,2003年5月,为机车车辆配套的连接板组成等零配件电镀锌时出现了电流效率低、局部无镀层的现象,经过分析研究排除了故障。     

两次锌酸盐镀锌故障的分析

我厂滚挂镀锌都是采用ＤＥ型锌酸盐镀锌工艺 ,其中添加剂ＤＥ与光亮剂一直使用同一厂家的产品。工作时控制锌碱比例为1∶(8～ 10 ) ,满负荷生产时 ,一般每月底用锌酸盐除杂剂处理一次 ,镀锌槽曾出现过两次故障。1　故障一(1)情况　挂镀和滚镀先后出现镀层粗糙、灰暗的现象 ,镀液分散能力和深镀能力差 ,生产难以正常进行。(2 )分析　故障产生的原因 :①锌碱比例失调 ,锌高碱低 ;②添加剂、光亮剂不足 ;③温度太高 ;④镀液杂质含量高。(3)排除过程　通过逐一检查、分析、调整 ,最后发现温度是引起这次故障的主要原因。锌酸盐镀锌控制最佳温度…     

多色打印中基于光谱的油墨选择——最佳油墨选择

描述了从给定油墨库中选择出一组八色油墨,建立最小化同色异谱的八色光谱打印模型的油墨选择算法.对于一个含有n种油墨的油墨库,这里有Cn8种油墨组合,当n很大时,油墨组合的数量就成了几何数字.有些明显不可能的油墨组合,通过解析法可以去除.首先,使用向量相关性分析法来去除没有可行性的组合.然后,用连续调相似评估每一备选油墨组的色度和光谱精确度.选择备选油墨组中对应有光谱精确度最高的一组油墨,定为八色打印过程的最佳油墨组以获取最小同色异谱的色彩复制.     

Selection of modules for mass customisation

Satisfying customer expectations is of paramount importance in today's markets. A customer expects to receive a product that meets as best as possible his/her expectations. To satisfy diversified requirements companies may focus on product families. For a specific customer the company has to select within a product family what will make a valid product. Then, in a just-in-time environment, the suppliers may have to provide the exact subassemblies corresponding to each product in a predefined time. This integration takes place by designing modules for the supplier. This paper proposes to extract customers’ behaviour patterns, in terms of the components required, using data-mining and entropy maximisation when selecting modules to be manufactured. Different methods for selection of modules are proposed. Computational tests are performed to evaluate performance of the selection methods with respect to the specified assembly time/resource level.     

Selection of inspector for visual inspection

This paper presents a statistical method for selecting the best inspector for visual inspection having the highest defect-finding ability among k(≥2) prospective inspectors.

A sample containing known number of defects are submitted to each of k prospective inspectors. As the sample size is increased, sampling variation decreases so that we have a better chance of selecting the truly best inspector, but at the same time the cost of sampling is also increased, The problem is how to determine the sample size required for selecting the best inspector with specified probability P*.

This problem is formulated from the indifference zone point of view with an application of the loss function which takes into consideration the opportunity cost of making a wrong selection and the cost of sampling. Minimax solution is obtained under the restriction that the best inspector is to be selected with the specified probability P*. The selection procedure is applied to the visual inspection of car body painting.     

工艺冷却用蒸发器的选择

在设计工艺冷却过程中,充分了解不同形式的工艺冷却用蒸发器,才能选择最适合工艺条件的换热器。本文对制冷工艺用的3种常用蒸发器的使用范围、结构设计以及使用中的注意事项等进行归纳总结,为制冷工艺设计人员、化工工艺设计人员等提供一些参考。     

Selection of Applications for a Material

Finding an application for a given (not necessarily new) material is an elusive problem. Methods for material selection to fill a given application are now well developed. But the inverse problem – that of finding applications for a new material – has no such established methodology. The article discusses some general approaches to the problem and demonstrates recent progress in implementing them.     

食品包装方法的选择分析

为了对食品包装方法选择问题进行分析,运用一种定量分析法建立包装方法选择模型.运用模型结合具体的实例进行方法选择的计算,结果证明了该方法的有效性.     

转子导程的参数选择

主要介绍转子导程的参数选择,并给出了实际设计时所碰到的挂轮选配问题的解决方案。     

光线示波器振子的选用

为了准确地测量记录各种被测信号，应当正确地选用振子的固有频率的阻尼，适当地选取被测信号大大小，保持信号源内阻Ｒｉ与振子的内阻ｒｇ相匹配，同时要正确地调整光点位置，以减小圆弧误差。     

Materials Selection for Semisolid Processing

The mechanical behavior of alloys in the semisolid state is very sensitive to the volume fraction of solid. In this paper, a simple criterion for processability in the semisolid range is introduced, based on the sensitivity of the volume fraction of solid with respect to minor temperature variations. In addition it is proposed that the processability in the semisolid state can be enhanced using microsegregated material.