金刚石磨粒纳米加工单晶碳化硅非连续表面机理研究  

Investigation on mechanism of nano-machining of single-crystal silicon carbide on non-continuous surface with diamond abrasive

作　　者：王一凡 唐文智 何艳 高兴军[1] 凡林 宋淑媛 WANG Yifan;TANG Wenzhi;HE Yan;GAO Xingjun;FAN Lin;SONG Shuyuan(School of Mechanical Engineering,Liaoning Petrochemical University,Fushun 113001,Liaoning,China)

机构地区：[1]辽宁石油化工大学机械工程学院,辽宁抚顺113001

出　　处：《金刚石与磨料磨具工程》2024年第1期92-100,共9页Diamond & Abrasives Engineering

基　　金：辽宁省博士科研启动基金计划(2022-BS-292);辽宁省教育厅科学技术研究项目(LJKZ0383);辽宁石油化工大学引进人才科研启动基金(2020XJJL-012);国家级大学生创新创业训练计划(202210148023)。

摘　　要：建立金刚石磨料纳米加工单晶碳化硅衬底的分子动力学模型,从矢量位移、切削力、晶体结构相变及缺陷等方面研究划痕对原子去除过程的影响以及划痕壁面的材料去除机理。结果表明:划痕区域原子的去除方法主要是剪切和挤压。划痕入口区壁面变形为弹性和塑性混合变形,划痕出口区壁面变形主要为塑性变形,增加纳米加工深度能够提高原子的去除量。衬底表面存在的划痕使纳米加工过程中的切向和法向切削力均降低,最大差值分别为300和600 nN,划痕区域原子的缺失是切向力下降的主要原因。磨粒的剪切挤压作用使碳化硅原子的晶体结构发生了非晶转化,产生了大量不具有完整晶格的原子,并且衬底表层的原子与临近的原子成键,形成稳定的结构。衬底温度受影响的区域主要集中在磨粒的下方,并向衬底的深处传递,在2、5和8?纳米加工深度下衬底温度之间的差值约为100 K。The molecular dynamics model of nano-machining a single-crystal silicon carbide substrate with a diamond abrasive is established.The effect of scratch on the atomic removal process and the material removal mechanism of the scratch wall were studied,considering vector displacement,cutting force,crystal structure transformation,and defects.The results show that the main methods for removing atoms in the scratched area are cutting and extrusion.The wall deformation of the scratch inlet zone invloves elastic and plastic mixed deformation,while the wall deformation of the scratch outlet zone is mainly plastic deformation.Increasing machining depth improves the removal of atoms.The presence of scratches on the substrate surface reduces both tangential and normal cutting forces in the nano-machining process,with the maximum difference being about 300 nN and 600 nN,respectively.The absence of atoms in the scratch area is the main reason for the decrease in tangential forces.The crystal structure of silicon carbide atoms is transformed by the shear and extrusion of the abrasive,resulting in a large number of atoms without a complete lattice.Moreover,atoms on the substrate surface form a stable structure by bonding with neighboring atoms.The affected area of substrate temperature is mainly concentrated under the abrasive and transferred to the depth of the substrate,with a difference of about 100 K between the substrate temperature at 2A,5A,and 8A nano-machining depths.

关 键 词：纳米加工 单晶碳化硅 非连续表面 位移矢量 切削力 相变 

分 类 号：TQ164[化学工程—高温制品工业] TG58[金属学及工艺—金属切削加工及机床] TG74[机械工程—机械制造及自动化] TH161