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木材是一种导电性极差的天然多孔性材料.为了制造具有导电性和电磁屏蔽性能的木质材料,使用了化学镀镍的方法在木材表面获得Ni-P合金镀层.利用扫描电镜观察了镀后木材单板的表面形貌,利用能谱分析和X-射线衍射分析技术分别研究了不同条件下的所得镀层的表面成分和结构,同时还测定了相应的表面电阻率和电磁屏蔽效能.从而探讨了镀层中磷含量与镀层结构、镀后单板的导电性和电磁屏蔽效能的关系.通过扫描电镜图片可以看到镀镍单板表面完全被镀层覆盖,使其具有极强的金属感.研究结果还表明,随着镀层中P含量的降低,镀层的微结构向晶态结构转变,且导电性和电磁屏蔽性能逐渐提高.当P含量低于2.37%时,镀层为晶态结构,表面电阻率和电磁屏蔽效能分别约为0.5Ω/□ 和55-60dB.图8表1参11.“,”Wood is a kind of porous natural material with very poor electro-conductivity, and it has almost no function of electromagnetic shielding. The method of electroless nickel plating was used to produce wooden material with electrical and effective electromagnetic shielding properties. Ni-P alloy layer was obtained on wood surface. The surface feature of plated wood veneer was observed by SEM and the surface composition and microstructure of the layer under different conditions were investigated by EDS and XRD respectively. Meanwhile, the relevant surface resistivity and electromagnetic shielding effectiveness were measured. Correlations of the phosphorous content in the layer to the structure of Ni-P alloy, electro-conductivity and electromagnetic shielding of plated veneers were discussed. SEM photos showed that the surface of electroless nickel plated veneers were covered with Ni-P alloy layer entirely,which made wood veneers more like metal. At the same time, the results showed that with the decreasing of the phosphorous content in the layer, the microstructure of Ni-P alloy layer transformed to be microcrystalline and electro-conductivity and electromagnetic shielding effectiveness were improved. When the phosphorous content was less than 2.37wt pct in the layer, the microstructure of Ni-P alloy layer was microcrystalline structure and its surface resistivity and electromagnetic shielding effectiveness were nearly 0.5Ω/□ and 55-60dB respectively.