菱形颗粒冲蚀磨损特性试验及仿真研究  

Experimental and Numerical Study on Erosion Characteristics of Rhomboid Particles

作　　者：杜明超 李增亮[1] 董祥伟[1] 范春永 刘斌 车家琪[1] DU Mingchao;LI Zengliang;DONG Xiangwei;FAN Chunyong;LIU Bin;CHE Jiaqi(Mechanic and Electronic Engineering,China University of Petroleum（East China）,Shandong Qingdao 266580,China)

机构地区：[1]中国石油大学(华东)机电工程学院,山东青岛266580

出　　处：《摩擦学学报》2018年第5期501-511,共11页Tribology

基　　金：山东省自然科学基金项目(ZR201709210292;ZR2018BA020);中央高校基本科研专项资金(18CX02153A);研究生创新工程资助(YCX2018054)~~

摘　　要：本文中针对单个硬质角形颗粒冲击金属材料表面的过程,设计了弹射试验装置,研究菱形颗粒冲击行为及冲蚀机理.采用高速摄像机,捕捉不同冲击速度v_i、冲击角度α_i和方位角度θ_i下颗粒的运动轨迹.建立了基于拉格朗日法的FEM-SPH耦合数值计算模型,借助于模型进一步分析了角形颗粒的运动学行为和变形凹坑形态.结果表明:冲击角α和方位角θ是决定颗粒旋转的关键因素,在某一固定冲击角αi下存在一个临界方位角θcr_i,当θi<θ_(cri)时颗粒冲击后发生前旋旋转,当θ_i>θ_(cri)时颗粒冲击后发生后旋旋转;冲击诱导的颗粒旋转对冲蚀机理的影响较大,颗粒前旋旋转对金属材料产生"耕犁"作用,后旋旋转对金属材料产生"撬起剔除"作用.颗粒的动能损失受到冲击角α_i和方位角θ_i的影响较大,临界方位角θ_(cri)下颗粒的动能损失最大,凹坑变形最严重.A catapult experimental device was designed to study the impact behavior and erosion mechanism of rhomboid particles impacting on metallic surfaces. Through the observation by high-speed camera, the motion trajectories of particles at different impact velocity vi, impact angle αi and orientation angle θi were captured. A coupled numerical model（FEM-SPH） based on Lagrange method was established to deeply analyze the impact behavior of angular particle and deformation of crater profile. The results show that the initial orientation angle θi, and the impact angle αi, which were the major factors, determined the erosion mechanism. For agiven impact angle αi, there existed a critical orientation angle θcri; if θ〈iθcri, the particle tumbled forwards, while for initial orientation angles θi〉θcri, the particle tumbled backwards after the impact. It also has been revealed that the rotation of particle highly influenced on the erosion mechanism. For example, a forwards rotating particle usually resulted in ＂ploughing＂ action, while＂machining＂ action can be observed in a backward impact process. In addition, the impact angle α and orientation angleθ had a great influence on kinetic energy loss of particle. In general, impacts at critical initial orientation corresponded to the peak value of kinetic energy loss.

关 键 词：单颗粒冲击试验 冲蚀机理 耦合数值计算模型 颗粒旋转 临界方位角 

分 类 号：TG115.58[金属学及工艺—物理冶金]