烧结钕铁硼的层裂强度及断裂机理  

Spall Strength and Fracture Mechanism of Sintered Nd-Fe-B

作　　者：万印 王焕然[1] 初广香 任春影 WAN Yin;WANG Huanran;CHU Guangxiang;REN Chunying(Key Laboratory of Impact and Engineering of Ministry of Education,Ningbo University,Ningbo 315211,China)

机构地区：[1]宁波大学冲击与安全工程教育部重点实验室

出　　处：《高压物理学报》2019年第5期107-111,共5页Chinese Journal of High Pressure Physics

基　　金：国家自然科学基金(11572164)

摘　　要：利用一级气体炮对烧结钕铁硼(Nd-Fe-B)永磁材料进行平板撞击实验,实现一维应变下的层裂;采用激光干涉测速技术,测量样品自由面粒子速度历史,确定了冲击压缩后层裂强度与加载应力的关系。结果表明:加载应力在0.375~2.512 GPa范围内时,层裂强度随着加载应力的增加先增加后减小,存在一个阈值,当加载应力超过该阈值时,材料发生压缩损伤,层裂强度随之减小。通过扫描电子显微镜观察样品断口形貌,发现在冲击载荷下烧结钕铁硼出现明显的穿晶断裂。The plate impact experiment was carried out through use of one-stage gas gun platform to study the spall of sintered Nd-Fe-B magnet subjected to one-dimensional loading.The free-surface velocity profile was measured using fiber velocity interferometer system for any reflector,and the spall strength was determined.The main results show that spall strength increases and then decreases when the impact stress increases from 0.377 GPa to 2.512 GPa.The reason is attributed to compression damage of the material when the impacted stress exceeds a stress threshold.Furthermore,the fractured morphology of sinter Nd-Fe-B was analyzed by scanning electron microscopy and the transgranular fracture was observed.

关 键 词：烧结钕铁硼 层裂强度 断裂机理 穿晶断裂 

分 类 号：O347.1[理学—固体力学] TM273[理学—力学]