摘要
首先通过平行对比了三种填充不同导电填料的硅橡胶材料的拉伸强度、扯断伸长率、恒定压缩永久形变、导电性及屏蔽性能,优选出镀银铝粉作导电填料;考察了镀银铝粉用量对硅橡胶材料的拉伸强度、伸长率、压变、微观形貌、导电性能的影响,最终确定镀银铝粉的填充体积分数为55%;结合导电橡胶制品对使用寿命的需求,进一步深入研究了导电硅橡胶材料在自然平贮老化及高温加速老化下的导电性能。结果表明:随老化时间的延长,体积电阻率不断增大,导电性能减弱。自然平贮老化60 d后,材料的体积电阻率基本不变;900d后,体积电阻率由初始值4.6×10-3Ω·cm增大至7.5×10-2Ω·cm。150℃老化30 d后,体积电阻率由初始值增大至9.5×10-2Ω·cm。填充镀银铝粉的导电硅橡胶材料在两种条件下老化后均能保持高的导电性;高温加速老化对导电性能的影响大于自然平贮老化。
First, the silver coated aluminum powder was selected as the optimal conductive filler by testing the mechanical strength, elongation ratio, compression set, electronic conductive properties and shielding effectiveness of three silicone rubber with different fillers parallel. Then the volume fraction of silver coated aluminum powder was fixed as 55% through investigating the effect of silver coated aluminum powder content on the mechanical strength, e- longation ratio, compression set, micro-morphology and conductive properties of rubbers. Based on the demand of rubber products for long service life, the conductive properties of these rubbers were investigated thoroughly after age- ing at environmental temperature and humidity and elevated temperature accelerated testing separately. The result showed that with the ageing time increased, the volume resistivity increased implying electronic conductivity weak- ened. The volume resistivity was almost not affected after initial 60 days ageing at environmental temperature and hu- midity, then increased from 4.6×10^-3Ω· cm to 7.5×10^-2 Ω· cm after 900 days ageing. The volume resistivity increased to 9.5×10^-2 Ω·cm after ageing at 150~C for 30 days. The result also indicated that the silver coated aluminum powder/ silicone rubber can retain the electronic conductive properties after ageing at two conditions. The ageing effect of ele- vated temperature accelerated testing was more significant than natural storage ageing.
出处
《宇航材料工艺》
CAS
CSCD
北大核心
2017年第1期47-51,共5页
Aerospace Materials & Technology
关键词
导电硅橡胶
镀银铝粉
体积电阻率
平贮老化
高温老化
Electronic conductive silicone rubber, Silver coated aluminum powder, Volume resistivity, Naturalstorage ageing, Elevated temperature accelerated ageing
