Experimental Study On Mechanism And Process Of Laser Cutting Ndfeb Magnetic Materials

Nd Fe B magnetic material is the third generation rare earth permanent magnet material.Due to its high magnetic energy product,high coercivity and high remanence,it is widely used in communications,medical,automobile manufacturing and other fields.With the improvement of living standards,the demand for Nd Fe B magnetic materials at home and abroad is increasing,and higher requirements are imposed on its production efficiency.At present,the processing method of Nd Fe B magnetic materials is still traditional machining methods such as wire cutting,grinding,slicing,drilling,etc.The equipment is large and takes up a lot of space,and the processing efficiency is low.As a new special processing method,laser processing has the characteristics of fast processing speed and high beam energy density.Based on this,this paper proposes the use of laser-cut Nd Fe B magnetic materials,analyzes the influence of laser cutting on the structure,magnetic properties and processing quality of Nd Fe B magnetic materials,and discusses the feasibility of laser special processing methods in magnetic material processing and manufacturing.The main research contents of this topic are:1.Starting from the characteristics of laser cutting and Nd Fe B magnetic materials,the effects of laser cutting Nd Fe B magnetic materials and the influence of temperature on the internal magnetic domains of Nd Fe B magnetic materials were analyzed.During the process of cutting the Nd Fe B magnetic material,the light energy generated by the laser is converted into heat energy,which acts on the surface of the material,causing the material to melt,thereby achieving the purpose of cutting.The effect of laser on the magnetic domain of Nd Fe B magnetic material is mainly two parts.The laser spot area is melted by heat to cause the magnetic domain to break.The vicinity of the incision reaches the Curie temperature of 340°C.The high temperature causes the magnetic domain structure to be destroyed.The destroyed magnetic domain can be destroyed.Combining with nearby magnetic domains to form a new magnetic domain structure,the two parts of the influence can be ignored.2.Based on the finite element analysis,the heat affected zone of laser cutting is simulated,and the temperature field simulation results of each time period in the cutting process are observed.It is observed that the laser processing of Nd Fe B magnetic material is only localized and the temperature rises in the spot area.The speed is fast and the cooling rate is fast.The temperature has the greatest influence on the material in this area.The effect of the temperature generated during laser processing on the overall magnetic domain of the material is not significant.3.Taking current,pulse width,frequency and oxygen pressure as parameters,slit width,roughness and slag amount as the measurement index,the process test of laser processing Nd Fe B magnetic material by single factor and orthogonal test,and The variance and range analysis of the test data are carried out,and the significant degree of influence of each parameter on the cutting quality is obtained.The optimal process test parameters are current 135 A,pulse width 0.75 ms,frequency 210 Hz,oxygen pressure 0.9 MPa.4.Study on the magnetization performance of Nd Fe B magnetic materials,magnetize the Nd Fe B magnetic materials after cutting,and then test their magnetic properties,analyze the measured BY curve,and compare the magnetic properties of traditional processing methods and laser processing methods.In comparison,it is concluded that the material properties after laser processing are similar to those of the conventional processed materials,and the peak,magnetic area,magnetic pole width,and full width at half maximum are within the normal range of variation.The macroscopic and microscopic observations of the morphology of Nd Fe B magnetic materials under the influence of temperature show that the magnetic domain structure destroyed by Nd Fe B magnetic material in laser cutting is almost negligible,and its magnetic properties are not Significantly affected.In summary,laser-cut Nd Fe B magnetic materials are feasible in practical processing applications.