颗粒碰撞阻尼的时效性研究  

Durability of particle impact dampers

作　　者：李海超[1] 王树林[2] 杜妍辰[3] 李生娟[2] 徐波[1] 蹇敦亮[2] 朱钰方[2] 

机构地区：[1]上海理工大学能源与动力工程学院,上海200093 [2]上海理工大学材料科学与工程学院,上海200093 [3]上海理工大学医疗器械与食品工程学院,上海200093

出　　处：《振动与冲击》2013年第15期156-160,177,共6页Journal of Vibration and Shock

基　　金：国家自然科学基金项目(51005157);教育部博士点基金资助项目(20113120110005);上海市纳米专项资助项目(1052nm02900);上海市大学生创新计划资助项目(SH1110252163)

摘　　要：颗粒碰撞阻尼是一种被动式振动控制器,其中颗粒材料在冲击过程中的尺度和形貌变化必然对其减振性能产生重要影响。初次探讨了带有中值粒度为35μm的锌颗粒的颗粒碰撞阻尼器在96小时内对正弦激励悬臂梁的阻尼减振的时效性。研究证明,主系统的响应在所考察的时间历程内出现了三次微幅上升,它是锌颗粒材料在冲击作用下结构和能态变化的结果。首先,随着冲击的进程,颗粒的冷焊效应阻碍了冲击器的运动速度,降低了冲击器的动量交换功能。第二,颗粒应变能和层错能的下降降低了系统的不可逆能耗。第三,颗粒的细化使其本身缺陷减少,进一步细化的难度增加,也使得系统内的不可逆能耗不断减小。这是主系统的响应随着振动历程出现了两次阶跃性微幅上升的主要原因。As a passive vibration absorber, the performance of particle impact damper is influenced by the evolution of particles size and morphology during the impact process. The durability of ball impact dampers with Zn particles of median diameter 35 μm as the damping agent in a container installed on a cantilever subjected to sinusoidal vibration was inspected in 96-hour impact test. The response of the primary system is slightly increased three times in the period investigated. It may be ascribed to the change of the morphology and energy state of Zn particles inside the absorber. With the impacts progressing, particles cold welding may occur, which decreases the velocity of the impactor (the ball) and consequently reduces the momentum exchange. On the other hand, the decreased strain energy and dislocation energy of Zn particles could also reduce the irreversible energy consumption of the system. At the same time, particle size decreasing along with the carrying on of working process makes particles difficult to be further cloven. All these may reduce the irreversible energy consumption. That is the reason why the cantilever response increases step by step with extended step length.

关 键 词：碰撞阻尼 减振剂 时间效应 微分析 

分 类 号：O328[理学—一般力学与力学基础] TB34[理学—力学]