舰载电子设备的三防设计

THREE-PROOFING DESIGN OF SHIPBORNE ELECTRONIC EQUIPMENT

防潮湿、防霉菌、防盐雾的三防设计是研制服役于海洋气候环境下的舰载电子设备的重要任务,产品研制时即应从材料应用、结构设计和工艺技术等诸方面进行系统性三防设计。正确、合理地应用耐蚀性好的金属材料和不长霉、耐老化的非金属材料是三防设计的基础。大多数的腐蚀都能通过合理的结构设计来避免,结构设计的合理性对设备的环境适应能力影响最大,是舰载电子设备三防设计的关键。恰当地应用材料改性、表面镀涂、浸渍、灌封和绝缘处理等具有良好防护效果的工艺技术,进一步提高设备的三防能力。目前,覆膜技术仅能解决L波段低频段以下电路组件的三防问题,微波/毫米波电路组件应用环境密封和电磁屏蔽复合技术可有效杜绝普遍性的电化偶腐蚀的发生,保证了组件的恶劣气候环境适应性和在0.1～10GHz工作频段内的屏蔽性能大于80dB,且可满足3m水深浸渍的防水要求。微组装了裸芯片等集成电路的毫米波收发组件则采用气密封装技术实现其三防设计,氦质谱检测漏率符合小于1×10-8Pa·m3/s的国军标要求,有效地保证了电路组件的可靠性。

The design of moisture-mildew-saltspray proofing to shipborne electronic equipment is an important mission for the shipborne electronic equipment operating at the ocean environment. It should be considered overall from the materials-application, structure design, process engineering and so on at the time of the product development. The accurate use of metal material with good corrosion resistance and the nonmetal material with good mildew-proofing and aging resistance is the basis of the design. Most corrosion could be avoided by the rational structural design. The rationality of the structural design would affect mostly the adaptive capacity to environment of the product and is the key factor for the moisture-mildew-saltspray proofing design of the shipborne electronic equipment. It would improve the proofing capability farther that the correct use of the material modification, surface coating/depositing, impregnation, encapsulation, insulation process and so on. At present, the coating-film technology would only solve the moisture-mildew-saltspray proofing problem in the circuit component under the L-band, but the encapsulation of application environment of micro/millimeter wave circuit component and the electromagnetic shielding composite technology could prevent effectively the ubiquitous galvanic corrosion, ensure that the component could adapt the inclement environment, and the shielding properties should be above 80 dB during the 0.1-10 GHz operating frequency, and meet the waterproof requirement of the three meter depth impregnation. Hermetic package is used at the millimeter-wave T/R components in which the bare chips are micropackaged for the moisture-mildew-saltspray proofing. The helium mass spectrum leakage detection rate should be less than 1 × 10^-8 Pa · m^3/s of the GJB requirement, which could ensure the reliability of the circuit component.