皮秒绿激光修锐青铜基金刚石砂轮损伤规律与机制  

Damage Law and Mechanism of Bronze-Based Diamond Grinding Wheel Sharpening with Picosecond Green Laser

作　　者：周远航 张健[1,2] 冯爱新 尚大智[1] 陈云 唐杰 杨海华 Zhou Yuanhang;Zhang Jian;Feng Aixin;Shang Dazhi;Chen Yun;Tang Jie;Yang Haihua(College of Mechanical and Electrical Engineering,Wenzhou University,Wenzhou,Zhejiang 325035,China;Key Laboratory of Laser Processing Robot of Zhejiang Province,Wenzhou,Zhejiang 325035,China;Chengdu Tool Research Institute Co.,Ltd.,Chengdu,Sichuan 610500,China)

机构地区：[1]温州大学机电工程学院,浙江温州325035 [2]浙江省激光加工机器人重点实验室,浙江温州325035 [3]成都工具研究所有限公司,四川成都610500

出　　处：《中国激光》2021年第6期191-200,共10页Chinese Journal of Lasers

基　　金：浙江省自然科学基金(LY20E050026);浙江省一般科研项目(Y201839918);温州市科技计划项目(G20190011,ZG2019002)。

摘　　要：为探究皮秒绿激光修锐青铜基金刚石砂轮的工艺规律与机制,实现青铜基体的选择性定量去除。首先采用10 ps绿激光作用于青铜/金刚石,利用S-on-1损伤测定法标定损伤阈值,确定皮秒激光修锐青铜/金刚石砂轮的最佳工艺参数范围。然后对青铜/金刚石砂轮表面进行修锐,通过激光共聚焦显微镜及其软件表征修锐表面形貌与表面粗糙度,探究激光峰值功率密度、重复频率、扫描次数对修锐效果的影响规律。结果表明,皮秒绿激光对青铜基体的去除机制主要为气化去除,很大程度上避免了金刚石磨粒的碳化,即使在高重复频率下,也无明显的热积累特征。在脉宽为10 ps、重复频率为400 kHz条件下,青铜基体与金刚石磨粒的损伤阈值分别为1.23×10^(9)W/cm^(2)、3.71×10^(11)W/cm^(2),两者相差两个数量级,青铜基体的选择性微量去除选择范围较宽,可通过调节峰值功率密度有选择性地去除基体,通过调节扫描次数定量去除基体。因此,采用皮秒绿激光可以选择性定量去除青铜基体且较好地保证金刚石磨粒的完整性。Objective Bronze-based diamond grinding wheels have been widely used,and their applications have increased sharply.However,they are difficult to dress after being blunt.Traditional dressing methods,such as mechanical and electrical dressing,have the disadvantages of large loss of dressing tools,low dressing efficiency,and serious environmental pollution.The laser dressing method has significant advantages such as high efficiency,environmental protection,controllability,and wide applicability.However,if using traditional long-wavelength continuous,millisecond,or nanosecond infrared lasers,their melting/vaporization ablation mechanism can easily cause carbonization damage of the diamond abrasive grains on the surface of the grinding wheel.The short-wavelength picosecond laser has the technical advantage of"electronic state"cold processing,which can simultaneously ensure the sharpening effect and inhibit the carbonization damage of diamond abrasive grains due to high temperatures.It has significant technical advantages when dressing the grinding wheel.In this paper,the picosecond green laser was used to radially sharpen the bronze-based diamond grinding wheel.The protocols of using a picosecond green laser to sharpen the bronze-based diamond grinding wheel were explored.Moreover,selectively and quantitatively removing of the bronze matrix at the grinding wheel was achieved.Methods Firstly,a 10 ps green laser was focused on the bronze/diamond surface,and the damage thresholds were calibrated by the S-on-1 damage measurement method.This method allowed to determine the suitable working conditions for picosecond green laser to sharpen the bronze/diamond grinding wheels.Secondly,a picosecond green laser was used to sharpen the surface of the bronze/diamond grinding wheel.Thirdly,the surface morphology and roughness were characterized using the laser confocal microscope.Finally,the effects of laser peak power density,repetition frequency,and scanning times on the sharpening effect were studied.Results and Discussions 1)Th

关 键 词：激光加工 皮秒激光 青铜基金刚石砂轮 激光修锐 损伤阈值 

分 类 号：TG743[金属学及工艺—刀具与模具]