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1.
通过赫尔槽试验与直流电解试验,研究了添加剂在焦磷酸盐溶液体系无氰电镀铜-锡合金(低锡)工艺中的作用。该体系镀液组成与工艺条件为:Cu2P2O7·3H2O25g/L,Sn2P2O71.0g/L,K4P2O7·3H2O250g/L,K2HPO4·3H2O60g/L,温度25℃,pH8.5,电流密度1.0A/dm2。采用扫描电镜(SEM)、X射线衍射(XRD)、能谱(EDS)、中性盐雾试验等方法研究了添加剂对镀层组成结构、外观、耐腐蚀性能及微观形貌的影响。结果表明,焦磷酸盐溶液体系无氰电镀铜-锡合金(低锡)时使用有机胺类添加剂可抑制Sn的析出,使合金镀层致密均匀,耐蚀性能好。镀层结晶主要为Cu13.7Sn结构,镀层中Sn含量为9%~11%。镀液中添加剂的使用量增加,则合金镀层中的Sn含量降低。  相似文献   

2.
以低碳钢圆饼为基体,在焦磷酸盐溶液体系中滚镀制备厚度为20μm以上的低锡铜锡合金。研究了Sn2P2O7的质量浓度、K4P2O7的质量浓度、添加剂JZ-1的用量、阴极电流密度及镀液温度对铜锡合金镀层组成和性能的影响。结果表明,这些因素对镀层的组成、性能和持续增厚都有一定的影响。低锡铜锡合金镀层可持续增厚的镀液组成与工艺条件为:K4P2O7 350~400g/L,Cu2P2O7·4H2O 20~25g/L,Sn2P2O7 1.5~2.0g/L,K2HPO4·3H2O 60g/L,添加剂JZ-10~0.5mL/L,pH8.5,阴极电流密度0.34~0.46A/dm2,镀液温度25~35℃,滚筒转速15r/min,循环过滤。在上述条件下对钢铁基体滚镀4h可获得平均厚度为20μm以上、锡的质量分数为12%~16%的铜锡合金镀层,该镀层与钢铁基体之间的结合力良好、耐蚀性能好,具有较好的机械性能与物理性能。  相似文献   

3.
研究了多种胺类高分子添加剂对焦磷酸盐体系无氰电镀白铜锡工艺及镀层微观形貌的影响。基础镀液的组成为:K4P2O7·3H2O200~250g/L,Cu2P2O7·3H2O16~19g/L,Sn2P2O712~15g/L,pH8.5~8.7。以IEP(水性阳离子季铵盐)、DPTHE(多胺高分子聚合物)和JZ-1(胺类化合物)作添加剂时,均可在较宽的电流密度范围内得到白亮铜锡合金镀层。以IEP作添加剂时,电镀白铜锡的电流密度上限最高为3.70A/dm2;以DPTHE作添加剂时,电镀白铜锡合金镀层的电流密度下限最低为0.09A/dm2,可抑制低电流密度区形成金黄色低锡铜锡合金。以IEP和DPTHE作添加剂时,均可使白铜锡合金镀层持续增厚,电镀50min可得到白亮、无裂纹的镀层,且IEP具有更明显的整平和细化晶粒作用。  相似文献   

4.
低锡铜-锡合金无氰电镀工艺   总被引:1,自引:1,他引:0  
通过赫尔槽试验研究了镀液组成、pH和温度对低锡铜-锡合金镀层外观的影响,并用方槽电镀试验研究了时间和电流密度对低锡铜-锡合金镀层的厚度与组成的影响,得到最佳镀液配方与工艺条件为:Cu2P2O7·3H2O 25 g/L,Sn2P2O7 1.0 g/L,K4P2O7·3H2O 250 g/L,K2HPO4·3H2O 60 ...  相似文献   

5.
通过赫尔槽试验与方槽试验研究了镀液组成和工艺条件对白铜锡电镀层外观与组成的影响。最佳镀液组成与工艺条件为:Cu2P2O7·3H2O16~19g/L,Sn2P2O712~15g/L,K4P2O7·3H2O200~250g/L,K2HPO460~80g/L,有机胺类添加剂JZ-11.2~1.8mL/L,pH=8.5~8.7,温度20~25°C,阴极电流密度1.0A/dm2。采用该工艺对基体施镀20min可得到厚度为5.09μm、锡的质量分数为40%~50%的均匀白亮的Cu-Sn合金镀层。Cu-Sn合金镀层的晶体结构以CuSn和Cu41Sn11为主,结晶细致、无微裂纹,显微硬度为372HV,耐蚀性能比相同厚度的光亮镍镀层好。  相似文献   

6.
在前期研究的基础上,在Cu2P2O7·4H2O 20 g/L、Sn2P2O71g/L、K2HPO4·3H2O 60g/L、pH=8.5、滚筒转速15 r/min、滚镀时间1h、采用循环过滤的工艺条件下,通过正交试验研究了焦磷酸钾质量浓度、电流、温度和添加剂JZ-1的用量对低碳钢上无氰滚镀铜锡合金(低锡)镀层厚度和含锡量的影响,确定了最优的工艺条件,并探讨了滚镀电流、温度和时间对铜锡合金镀层的组成与镀速的影响.试验证明,当K4P2O7为300 ~ 350g/L、添加剂JZ-1为0.5mL/L、镀液温度为30~35℃、电流密度为0.38 ~ 0.48 A/dm2时,可获得厚度5 μm以上、锡含量为9%~ 11%的铜锡合金镀层,其外观光亮、金黄,与钢铁基体的结合力良好,具有一定的硬度与耐腐蚀性能,可以替代钢铁基材预镀镍和氰化预镀铜工艺.  相似文献   

7.
通过赫尔槽试验和方槽试验研究了新型添加剂K-1(胺类与环氧化合物的缩合物)用于焦磷酸盐溶液体系电镀白铜锡的镀液组成和工艺。结果表明,最佳镀液组成和工艺条件为:K_4P_2O_7·3H_2O 300 g/L,Sn_2P_2O_7 8 g/L,Cu_2P_2O_7·4H_2O 12 g/L,添加剂K-1 2.4~4.0 m L/L,还原剂2 g/L,p H 8.5~9.5,电流密度0.7~1.2 A/dm2,温度25°C。添加剂K-1作为光亮剂,具有细化晶粒的作用,但不具有整平能力,其用量为0.8~4.0 m L/L时均能得到Sn含量为45%~55%的白铜锡镀层。  相似文献   

8.
梁均方 《广东化工》2004,31(7):19-20
本文报导了一种用焦磷酸盐代替剧毒氰化物的仿金电镀新工艺,总结出镀层中铜、锌、锡含量不同对仿金镀层色泽的影响,由于镀液中采用了新的络合剂和添加剂,因此本工艺具有阳极溶解性能良好,允许电流密度高,在规定的阴极电流密度下仿金镀层色泽逼真,镀层光亮等优点.  相似文献   

9.
在304不锈钢表面脉冲电镀低锡Cu-Zn-Sn仿金合金,镀液组成为:CuSO4·5H2O 0.18 mol/L,ZnSO4·7H2O 0.06 mol/L,Na2SnO3·3H2O 0.05 mol/L,Na3C6H5O7·2H2O 22.66 g/L,Na2CO325 g/L,羟基乙叉二膦酸(HEDP)100 mL/...  相似文献   

10.
Ⅰ前言为满足电镀仿金灯具的需要。我们借助当今氰化光亮铜锡合金添加剂的新成果;在南京大学配位化学研究所庄瑞舫教授指导下,探索,试制了一组仿金镀液。并实施了以光亮氰化铜锡合金体系为基  相似文献   

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Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

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Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.  相似文献   

17.
In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.  相似文献   

18.
Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.  相似文献   

19.
收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.  相似文献   

20.
收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。  相似文献   

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