【作者】 陈岱民；

【导师】 李占国；

【作者基本信息】 长春理工大学 ， 机械制造及其自动化， 2013， 博士

【摘要】 利用激光在金属材料上进行加工孔的技术有着突出的特点,如加工精度比较高、加工效率比较高、加工成本相对比较低的综合技术,在激光应用方面,它是最先在生产实际中应用的技术,也是利用激光进行生产加工的主要技术领域。随着近代工业和科学技术的迅速发展,使用硬度大、熔点高的材料越来越多,而传统的加工方法已不能满足某些工艺要求。本文针对激光加工领域中激光打微小孔时存在的不足,结合激光打孔的实际情况,以及激光与被加工材料之间相互作用的关系,研究分析激光光束能量作用于被加工金属材料上的过程,构建激光在金属材料上进行孔加工的温度场数学模型,编写分析程序,并嵌入到ANSYS有限元分析软件的后处理程序中,利用该软件对被加工材料碳钢的激光打微孔过程中的温度场变化进行了仿真分析,为优化激光打孔工艺参数提供了理论依据。在理论分析的基础上,利用数控YAG激光多功能加工机以碳钢为主进行了实验分析,选用不同厚度、不同材料进行激光打孔试验,系统分析了激光功率、激光脉冲宽度、激光重复频率、辅助气体、离焦量等对小孔的上、下孔径及锥度的影响,比较并分析了模拟值和试验值,验证了有限元法仿真分析的可行性,提出了YAG激光在碳钢上打微孔时各项工艺参数的选择方法。采用双因素无重复的试验方法和无交互作用的正交试验方法分析了激光功率、激光脉冲宽度、激光重复频率对激光打孔质量的影响程度,其分析结果与计算机模拟仿真结果和试验数据分析结果相吻合,结果表明理论分析研究是正确的,分析研究了重铸层形成机理,以及不同含碳量在激光加工时重铸层的厚度变化,不同激光参数对重铸层厚度的影响,和含碳量和激光频率对加工孔表面精度的影响。更多还原

【Abstract】 Laser drilling technology is one of the earliest technologies to be utilized in the practical laser processing, and it is also one of the main processing applications using laser. It is a comprehensive technology which has many advantages, such as the high accuracy, the good commonality and the high cost-effectiveness. With the rapid development of modern industry and science and technology, more and more high hardness and high melting point materials have been used. Thus, the traditional processing methods cannot meet certain technical requirements any more.On the basis of the characteristics of laser and interaction mechanism of the laser and the processing material, this paper aims for the actual use of the technology in processing. As the mathematical model of temperature field of laser drilling has been established, the analysis program was written on the basis of the model which will be embedded in the finite element analysis software ANSYS post-processing procedures, which was used in stimulating the laser drilling of carbon steel. It will prepare parameters for optimizing procedure.On the basis of theoretical analysis, a test was made in different thickness and different materials by using CNC YAG laser. The primary test material was carbon steel. The researcher analyzed the influence on bore diameter and conical degree by laser power, pulse width, impulse frequency, focused diameter of the beam, and the assistant gas and so on. The researcher also compared the simulation value and test value, proved the feasibility of simulation, and presented the selection method of procedure parameters in laser drilling. The experimental methods of the double factors without repeating and the orthogonal without interaction are adopted to analyze how much the laser drilling quality would be affected by laser power, impulse width, and impulse frequency. It is turned out that the theoretical analysis matched with the computer simulation.更多还原