正电子湮没谱表征热处理工艺对聚碳酸酯力学性能的影响
Effect of Heat Treatment on Mechanical Properties of Polycarbonate Exposed by Positron Annihilation Spectroscopy
孙琦伟 1王韬 1许雪婷 2葛勇 1王博伦 1郎建林 1陈宇宏 2颜悦1
作者信息
- 1. 北京航空材料研究院股份有限公司,北京 100095;北京市先进运载系统结构透明件工程技术研究中心,北京 100095
- 2. 中国航发北京航空材料研究院,北京 100095;北京市先进运载系统结构透明件工程技术研究中心,北京 100095
- 折叠
摘要
考察了退火和淬火2种热处理方法所用的不同热处理温度和时间对聚碳酸酯力学性能的影响,并采用正电子湮没谱分析经过不同热处理工艺后聚碳酸酯内部自由体积的含量.结果表明,在玻璃化转变温度附近及以上进行一定时间的淬火可通过增大内部自由体积含量和尺寸来显著改善聚碳酸酯的韧性,降低材料的屈服强度和弯曲强度,提高缺口冲击强度和拉伸强度.在玻璃化转变温度以下,淬火不能改变材料内部的自由体积,不能提高材料的韧性.退火只能降低材料内部自由体积的含量和尺寸,但不受温度和时间的影响,且材料的拉伸强度、断裂伸长率和缺口冲击强度大幅降低.
Abstract
The influence of different heat treatment temperatures and time used for annealing and quenching on the mechanical properties of polycarbonate(PC)was investigated.Positron annihilation spectroscopy(PALS)was used to analyze the free volume content of PC after different heat treatment processes.The results show that the toughness of PC,especially the notch impact strength and fracture strength can be improved significantly by quenching near or above glass transition temperature for a period of time,while the yield strength and bending strength can be reduced.The toughness of PC is affected by the internal free volume content and size which will be changed through quenching near or above glass transition temperature.By this way,the internal free volume content and size of PC which is quenched near or above glass transition temperature are similar with unheated PC.However,the toughness cannot be improved by extending quenching time below glass transition temperature because the free volume content and size have been reduced.The internal free volume content and size of PC can be only reduced by annealing,which is not affected by annealing temperature or time,resulting in a significant decrease in the tensile fracture strength,elongation at break,and notch impact strength of PC.
关键词
正电子湮没谱/退火/淬火/聚碳酸酯/力学性能Key words
positron annihilation spectroscopy/annealing/quenching/polycarbonate/mechanical property引用本文复制引用
出版年
2024
NETL
NSTL
万方数据