摘要
通过模拟实际工作状况对丁腈橡胶密封圈进行了热油加速老化试验,研究了密封圈压缩永久变形的变化规律,采用红外光谱、热失重、示差扫描量热、扫描电子显微镜等,考察了丁腈橡胶密封圈在液压油中化学结构、热性能、断口形貌的变化情况。试验结果表明,随着老化试验的进行,密封圈压缩性能逐渐下降,热分解温度与玻璃化转变温度均有所提高,分析在应力作用下密封圈的分子链段发生取向,约束了分子链的各种松弛行为,是老化过程密封圈压缩性能下降,热性能提高的主要因素。另外老化后橡胶断口形貌趋于光滑且出现孔洞,红外光谱显示添加成分含量降低,密封圈与液压油之间存在物质交换,物质交换也是造成密封圈压缩性能下降的另一个因素。
Under simulated conditions hot hydraulic liquid accelerated aging testing of nitrile-butadiene rubber seal was carried out.By the FT-IR,DSC,TGA and scanning electron microscopy methods ; the variation of chemical structure,thermal property and fracture morphography of rubber seal was analyzed in hydraulic fluids.The results show that after aging testing,the compression property of the rubber seal decreased gredually,both thermal decomposition temperature and glass transition temperatures increase.On the one hand,under the effect of stress,molecular chain segments have been orientated in some directions,restricting the relaxation of molecular chains,which resulted in the compression property decreased and the thermal property increased.On the other hand,the tensile fracture surface tends to be smooth and have holes,and the content of additive decreases,which means embrittlement has occurred to rubber seal and there have been mass exchange between rubber seal and hydraulic fluid,this is the other factors of compression property decreased.
出处
《宇航材料工艺》
CAS
CSCD
北大核心
2014年第4期64-67,共4页
Aerospace Materials & Technology
基金
中国航空工业集团公司北京航空材料研究院基金项目(KF53120730)
关键词
丁腈橡胶
密封圈
老化
机理
Nitrile-butadiene rubber
Seal
Aging
Mechanism
