摘要
目的研究某密封橡胶材料在工况环境下的老化规律和特性,开展静载荷/温度/介质等多因素耦合的加速老化试验。方法设计3种老化条件(90℃热空气、90℃热空气压缩、90℃热油压缩)模拟实际服役环境开展实验室加速研究。通过质量、硬度、压缩永久形变率等橡胶老化前后宏观性能变化,结合其化学结构和微观形貌变化进行老化特性研究。结果热油压缩老化条件下,橡胶质量随时间变大,硬度变小,压缩永久形变变大,热稳定性变差,化学结构变化较小;热空气压缩条件下,压缩永久形变变大,其他物化性能变化较小;热空气条件下,硬度变大,烷基含量减少,其他变化较小。扫描电镜结果显示,2种压缩条件下,橡胶表面都出现颗粒状物质和条状纹理。以上结果说明,油在隔绝外界氧气的同时,会渗透到橡胶内部,引起软化,热空气介质加速橡胶热氧老化和材质硬化,压缩条件在抑制热氧老化同时,可加速应力松弛等物理老化作用的发生。结论密封橡胶在不同服役环境下发生的主要老化反应并不一致,在热空气下,橡胶性能退化与热氧老化等化学老化作用有关,而在油介质和压缩状态下,橡胶性能劣化与物理老化作用更相关。
The work aims to explore the aging laws and characteristics of a certain sealing rubber material under in-service conditions and conduct accelerated aging tests with multiple factors combined,including static loads,temperature,and medium.Three types of aging conditions(90℃hot air,90℃hot air compression,90℃hot oil compression)were designed to simulate the actual service environment for laboratory-accelerated research.The changes in macroscopic properties such as mass,hardness,and compression set before and after aging were studied.The aging characteristics were studied combined with changes in its chemical structure and microscopic morphology.Under the aging conditions of hot oil compression,the mass of rubber increased with time,the hardness decreased,the compression permanent deformation increased,the thermal stability deteriorated,and the chemical structure changed slightly;Under the condition of hot air compression,the compression permanent deformation increased,while other physical and chemical properties showed minimal changes;Whereas under the pure hot air condition,the hardness increased,the alkyl content decreased,and other changes were minor.Results from scanning electron microscope showed that granular substances and striated textures appeared on the surface of rubber samples under both compression conditions.These results illustrated that oil could penetrate into the rubber causing softening while isolating external oxygen;Hot air medium accelerated thermal-oxidative aging and material hardening in the rubber,And the compression conditions inhibited the thermo-oxidative aging while accelerating the physical aging processes such as stress relaxation.The primary aging reactions of sealing rubber under different service environments are not consistent.Under the hot air condition,the degradation of rubber properties is closely related to the chemical aging process such as thermo-oxidative aging.However,when immersed in oil medium with compression states,the deterioration of rubber performance is more associated with physical aging effects.
作者
薛梅芳
吕天一
陶友季
赵雪茹
彭敦诚
徐至酉
XUE Meifang;LYU Tianyi;TAO Youji;ZHAO Xueru;PENG Duncheng;XU Zhiyou(Guangdong Provincial Key Laboratory of Environment Adaptability Evaluation and Testing Technology for Polymeric Materials,China National Electric Apparatus Research Institute Co.,Ltd.,Guangzhou 510663,China;State Key Laboratory of Environmental Adaptability for Industrial Products,China National Electric Apparatus Research Institute Co.,Ltd.,Guangzhou 510663,China;CVC Testing Technology Co.,Ltd.,Guangzhou 510663,China)
出处
《装备环境工程》
CAS
2024年第5期132-141,共10页
Equipment Environmental Engineering
基金
国家重点研发计划(2022YFF0608700)
中国电器科学研究院股份有限公司科技项目(SCRN2022100)。
关键词
密封橡胶
热油压缩
热空气压缩
热空气
加速老化
老化机制
sealing rubber
hot oil compression
hot air compression
hot air
accelerated aging
aging mechanism
