离子束活化对GF/PEEK金属化涂层结合强度的影响

Bonding Strength of Metallized Coatings on GF/PEEK Surface after Ion Beam Activation

为了解决玻纤/聚醚醚酮复合材料(GF/PEEK)因界面惰性导致的金属化涂层结合强度弱的问题,采用低能离子束对基材进行表面活化处理,再以磁控溅射和电镀技术制备Cu膜,从而实现复合材料表面大厚度、高性能金属化层的制备。分别采用Ar、H_(2)、O_(2)和H_(2)+N_(2)混合气体进行离子束活化,通过对比活化前后基材的润湿性能、微观形貌和表面特性变化,对离子束活化的作用机理展开研究,制备Cu膜并对Cu膜的结合强度进行判定,探讨不同气体活化对结合强度的影响规律。结果表明,经离子束活化后,复合材料的表面润湿性得到显著改善,极性官能团的相对含量明显提高,表面和浅表面玻纤的结构完整性受到破坏,采用Ar、H_(2)、O_(2)和H_(2)+N_(2)离子束活化处理后,Cu膜的结合强度由未经活化的0.1MPa逐渐提高至0.4 MPa、1.49 MPa、7.97 MPa和11.51MPa。离子束活化技术能够有效改善复合材料的表面活性,显著提高金属化涂层的结合强度,延长金属化层的使用寿命,为其工程化应用奠定了理论和数据基础。

GF/PEEK composites,prepared with polyetheretherketone as the substrate and glass fiber as the reinforcing phase,can balance mechanical properties with lightweight engineering needs and have become one of the most popular materials for engineering applications.However,GF/PEEK composites have poor electrical,thermal,and magnetic conductivity.Therefore,when specific functionality,such as electromagnetic shielding,filtering,and thermal radiation resistance,is required,a thin metal layer must be prepared on the surface to achieve structural–functional integration without changing the basic properties of the material.However,as the GF/PEEK composite is particularly chemically inert,it has weak molecular interactions at the interface with the metal layer and weak bond strength because of the heterogeneous material mismatch at the interface.This has limited the research and application of metallization.To address these problems,a Hall ion source is used to generate a broad,low-energy ion beam for the surface activation of the substrate,thereby improving the surface activity of the material.On this basis,a Cu conductive seed layer is deposited by DC magnetron sputtering technology,after which a Cu thickening layer is electroplated on the seed layer,thus realizing the preparation of large-thickness,high-performance metallic Cu films on the surface of composite insulating materials.For the ion beam activation,the working gases are Ar,H_(2),O_(2),and an H_(2)+N_(2) mixed gas.The mechanism of the ion beam activation is investigated by comparing the changes in the wetting properties,micromorphology,and surface properties of the substrates before and after activation with the different gases.On this basis,the Cu films are prepared,and the binding strengths of the Cu films are determined by qualitative and quantitative methods to explore the influence of the activation of the different gasses.The results showed that the structural integrity of the GF/PEEK material surface and shallow surface glass fibers is significantly disrupted after ion beam activation,and the surface energy gradually increases from 41.57 to 69.83,70.38,73.65,and 75.05 m J·m~(-2)for the different gasses,respectively,with significant improvement in the surface wettability of the material.After activation,the original long chain structure of the substrate is interrupted,many short chains and free radicals are generated,the concentration of polar functional groups on the surface is significantly increased,and the surface activity is improved.After activation,the molecular interaction between the polymer substrate and the metallic copper film is enhanced,and they adhere to each other more effectively.The sufficiently high adhesion energy counteracts the stress caused by the thermal increase and decrease;therefore,the film substrates are more closely bonded to each other.After activation with the Ar,H_(2),O_(2),and H_(2)+N_(2) ion beams,the bond strength of the Cu coatings is improved from 0.1 MPa/Level 5 without activation to0.4 MPa/Level 2,1.49 MPa/Level 1,7.97 MPa/Level 0,and 11.51 MPa/Level 0,respectively,of which the O_(2) and H_(2)+N_(2) showed the most obvious improvement.The ion beam activation technology can effectively improve the surface activity of the composite materials,significantly increase the bonding strength of metallized coatings,and prolong the service life of metallized layers,which presents the theoretical and data basis for its engineering application.