摘要
以次亚磷酸钠为还原剂,在水曲柳单板表面化学镀铜制备电磁屏蔽复合材料。研究了镀液温度和pH值对镀层成分及电性能的影响。分别采用扫描电镜(SEM)、能谱(EDAX)和X射线衍射(XRD)分析化学镀铜单板的表面形貌、镀层成分和晶体结构。用低电阻测定仪和频谱仪分别测定了复合材料的表面电阻及电磁屏蔽效能。实验结果表明,镀铜单板依然保持木材的孔隙结构,但表面已完全被镀层所覆盖。施镀过程中,温度和pH值对镀层成分、表面性貌及电性能均有一定的影响。过高或过低的温度和pH值对Cu的沉积均是不利的。温度和pH值分别控制在70℃和9.8左右制得的镀铜水曲柳单板的表面电阻率较低,电磁屏蔽效能较高,镀层铜为单质铜,夹杂少量Ni,P,Cu2O,排列相对紧密。横纹和顺纹的表面电阻率分别为0.139Ω/cm2和0.111Ω/cm2,在频率为10kHz^1.5GHz范围内,电磁屏蔽效能约55~60dB。
Electromagnetic shielding composite was prepared by electroless copper plating using hypophosphite as reducing agent. Effect of temperature and pH value of plating solution on composition and electrical performance of coatings were investigated. Surface morphology of electroless plated veneers and the composition of the copper coating were observed and determined by scanning electronic microscope（SEM） and energy dispersive X-ray analysis（EDAX）. Crystal structure of the coating was investigated by X-ray diffraction（XRD）. Low-resistance measuring instrument and spectrum analyzer were used for measuring surface resistance and electromagnetic shielding effectiveness（ESE）. The results show that porous structure of wood itself still exists on plated veneer, and the surface of wood veneer is covered by the coating entirely. It is found that temperature and pH value have effects on composition, surface morphology of the coating and electrical performance of the composite in the course of plating. Excessively low or high temperature and pH value are adverse for copper deposition. The surface resistivity and ESE of plated veneer under temperature 70℃ and pH value 9.8 are lower and higher, respectively. Copper is elementary substance mixed a small quantity of nickel, phosphour and cuprous oxide in the coating which is more compact. The resistivity transverse and parallel fiber direction are 0. 139Ω/cm^2 and 0. 111Ω/cm^2 , and the ESE is about 55-60dB in the frequencies from 10kHz to 1.5GHz.
出处
《材料工程》
EI
CAS
CSCD
北大核心
2008年第4期56-60,共5页
Journal of Materials Engineering
基金
黑龙江省在站博士后资助项目(LRB05-321)
关键词
水曲柳单板
化学镀铜
表面电阻率
电磁屏蔽
复合材料
fraxinus mandshurica veneer； electroless copper plating； surface resistivity； electromagnetic shielding
composite
