高强度船体结构钢DH36的动态力学性能研究  

Investigation on Dynamic Mechanical Performances of DH36 High Strength Ship-hull Steel

作　　者：郭伟国[1] 史飞飞[1] 刘凤亮[1] 

机构地区：[1]西北工业大学航空学院,陕西西安710072

出　　处：《兵工学报》2009年第S2期203-207,共5页Acta Armamentarii

基　　金：国家自然科学基金项目(10872169);国防基础科研项目(A2720060277);爆炸科学与技术国家重点实验室基金项目(KFJJ08-11)

摘　　要：为了研究新型DH36中厚船板钢在极端力学环境下的动态力学性能,采用电子万能试验机和改进的分离式Hopkinson拉、压杆装置对圆柱状DH36钢试样进行了应变率从0.001/s到7 000/s,温度从77 K到1 073 K范围的单轴拉伸、压缩试验,同时进行了中断试验以检查温度和应变率历史对材料性能的影响。试验结果表明:经过滚轧的DH36中厚船板钢是力学各向同性的;此钢的力学性能对温度和加载率非常敏感,但随温度升高到室温或更高温度值后其对温度敏感性下降,进一步推得该材料若经高温焊接所引起的材料性能变化不显著;随应变率增加该材料的破坏失效应变递减,在应变率为7 000/s时失效应变为20%,表现出应变率脆化特性;在室温以上动态应变时效发生,发生的温度区随应变率增加向更高温度区移动,它主要是Snoek间隙原子气团与位错的相互作用结果。To investigate dynamic mechanical performances of newer DH36 medium thickness ship-hull steel in the extreme mechanical environments,the uniaxial tension and compression tests were performed on cylindrical samples,using electronic universal test machine and improved Hopkinson tension and compression equipment in the range of strain rates from 0.001/s to 7 000/s and at initial temperatures from 77 K to 1 073 K.Meanwhile,the interrupting tests were also carried out to check the influences of temperature and strain-rate histories on the material performances.The experimented results show that the hot-rolled DH36 medium thickness ship-hull steel is mechanically isotropic;its mechanical performances are very sensitive to the temperature and loading rate,but the sensitivity will decrease if the temperature raises to room temperature or higher,which implies that the higher temperatures welding will not influence the material performances remarkably;the failure strain of DH36 steel decreases with increasing of strain rates,which is about 20% under a strain rate of 7 000/s and implies the induced brittleness change by the strain rate;the dynamic strain aging occurs at room temperature or higher,the aging temperature range will shift to higher temperatures with increasing strain rate,due to the interaction between the Snoek interstitial atom atmosphere and dislocation motion.

关 键 词：DH36钢 应变率 温度 失效应变 动态应变时效 

分 类 号：TG142.41[一般工业技术—材料科学与工程]