首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
锌镍合金电镀工艺的研究   总被引:3,自引:0,他引:3  
本文主要介绍了在柠檬酸盐体系中,使用791光亮剂和聚醚多元醇作添加剂,可以得到结晶细致,具有一定光亮度的锌镍合金镀层。对于该工艺的镀液成分及操作条件,作了详细的研究,并确定NiSO_4·7 H_2O90-100 g/L,ZnSO_4·7 H_2O 50-60 g/L,NaCl 8-10 g/L,H_3BO_3 30-35 g/L,柠檬酸钠80-100 g/L,791光亮剂4-6 mL/L,聚醚多元醇0.5-1 mL/L,pH 3.8-4.4,T=40-56℃,Dk1.5-4A/am~2。另外对镀液性能和镀层性能也作了仔细测试。通过腐蚀试验,发现这种含镍10-15%的锌镍合金镀层,具有优良的抗蚀性能,可作代镉镀层或防护装饰性电镀的底层。  相似文献   

2.
开发了一种锌铁低磷三元合金电镀工艺,镀液组成及工艺条件为:ZnCl270~100g/L,KCl160~200g/L,CH3COONa5~40g/L,CH3COOH2~10mL/L,FeCl25~10g/L,稳定剂5~30g/L,含磷细化剂0.5~20.0g/L,光亮剂15~25mL/L,室温,pH2.5~4.0,电流密度0.5~2.0A/dm2。测试了镀液的深镀能力、光亮电流密度范围、缓蚀效果及耐老化性能。以热震法和弯曲法测试了镀层的结合力,采用扫描电镜和透射电镜分析了镀层的微观形貌。通过在5%(质量分数)NaCl溶液中的极化曲线测量以及中性盐雾试验,考察了镀层的耐蚀性。该新型锌铁磷三元合金工艺成本低、稳定,镀层耐热冲击和耐腐蚀的性能优良。  相似文献   

3.
采用新的添加剂和配位剂实现了从以ZnO7~10g/L、NiSO4·6H2O5~10g/L和NaOH120~140g/L为主要成分的碱性镀液中制备含镍量为12%~15%(质量分数)的锌镍合金镀层。介绍了镀液各成分对镀层性能的影响。中性盐雾试验结果表明,含镍量为13.4%的锌镍合金镀层在镀态条件下具有最佳的耐蚀性。该锌镍合金镀层若未钝化,在中性盐雾试验中耐白锈的时间为24h,而经彩虹色或本色钝化后,96h后出现少量灰白色腐蚀点,290h后才出现白色腐蚀点。  相似文献   

4.
无氰电镀高锡铜锡合金工艺   总被引:1,自引:1,他引:0  
介绍了一种高锡含量的铜锡合金电镀工艺,镀液配方为:320~400g/L焦磷酸钾,5~12g/L焦磷酸铜,20~35g/L焦磷酸亚锡,5~10g/L柠檬酸钠,30~50g/L磷酸氢二钾,30~50g/L氨三乙酸,10~30mL/L配位剂,10~20mL/L光亮剂。讨论了镀液中各组分的含量及工艺条件(温度、电流密度、搅拌)对镀液和镀层性能的影响。给出了电镀常见故障的处理方法。  相似文献   

5.
电镀银镍合金工艺及其在电接触材料生产中的应用   总被引:1,自引:1,他引:1  
介绍了用于生产电接触材料的银镍合金电镀工艺。镀液配方为:30~80g/LKAg(CN)2,10~30g/LKCN,10~20g/LK2CO3,0.2~0.3g/LCdSO4,0.1~0.2g/L糖精,100~150g/L络合剂Ⅱ,5~10g/L镍盐,1~2g/LK2SeO3。介绍了镀液中各组分的作用、镀液的维护及杂质影响与去除方法。讨论了镀液中各组分的含量及工艺条件(温度、电流密度、搅拌方式)对镀液和镀层性能的影响。该工艺操作简单,工艺范围宽,电流效率高,沉积速度快。  相似文献   

6.
电镀耐蚀性锌-镍合金工艺的研究   总被引:1,自引:0,他引:1  
介绍了一种新的电沉积锌-镍合金工艺和镀液配方,采用了新的钝化液配方及相应的工艺对锌-镍合金进行钝化处理。介绍了锌-镍合金镀液的维护方法,并对该镀层进行了性能测试。该配方具备工艺简单、操作方便、镀层易钝化等优点。  相似文献   

7.
化学镀镍复合配位剂的研究   总被引:1,自引:0,他引:1  
采用对比试验和正交试验,以镀速、孔隙率、镀液稳定性和镀层硬度为评价指标,研究了单一配位剂及复合配位剂对镀液和镀层性能的影响,得到了复合配位剂的最优组合:8.4g/L乳酸,6g/L苹果酸,9g/L柠檬酸,8g/L丁二酸,1g/L丙酸。采用该复合配位剂的工艺配方可提高镀液使用寿命,获得性能优良的镀层。  相似文献   

8.
比较了酸性锌-镍合金镀层与碱性锌-镍合金镀层的性能。结果表明:酸性锌-镍合金电镀工艺较碱性锌-镍合金电镀工艺具有更高的镀速,但均镀能力较差。在相同的外部控制条件下,酸性锌-镍合金镀层和碱性锌-镍合金镀层的耐蚀性及结合力相当。  相似文献   

9.
为了拓展铝及铝合金的应用范围,采用二次浸锌+碱性化学镀镍+酸性化学镀镍+化学浸镀仿金的组合工艺,开发了一种新的铝及铝合金化学浸镀仿金工艺,探讨了主要成分和工艺条件对仿金镀层质量的影响,确定工艺条件如下:SnSO48~10 g/L,CuSO41.2~1.5 g/L,配位剂(酒石酸或柠檬酸)10~15 g/L,H2SO410~20 mL/L,XT-08B稳定剂10~12 mL/L,氢氟酸40~50 mL/L,氟化铵1~2 g/L,温度15~35°C,时间10~15 min。所得仿金镀层色泽典雅纯正,结合力好,工艺操作简便,对环境污染小,耐蚀性可与电镀仿金层媲美,具有较好的应用前景。  相似文献   

10.
研究出一种钛合金无氰碱性镀铜工艺。通过实验,确定了最佳的镀液配方及工艺条件为:CuSO_4·5H_2O 25~30g/L,KOH 90~100g/L,K_2CO_3 30~50g/L,DS116添加剂110~130mL/L,pH值9.0~10.5,电流密度0.5~4.0A/dm~2,温度40~60℃。同时,对镀层和镀液的性能进行了测试。  相似文献   

11.
12.
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   

13.
14.
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   

15.
16.
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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号