The Research On Measurement Of Superabrasive Absorption To YAG Laser And Numerical Simulation

The laser processing essence is to change the material physical or chemical structure by absorbed laser energy, thus fulfills a certain processing purpose. Therefore, research on measuring method of the absorption coefficient is the foundation to the laser processing, and it has important significance in practical application.Laser truing and dressing of superabrasive grinding wheel as one kind new technology is demonstrating powerful prospect in development day by day. In the process of laser truing and dressing superabrasive grinding wheel, a part of laser radiating to grinding wheel is absorbed by abrasives and bond, another part is reflected or penetrates through the abrasives to act on bond. The essence of laser truing and dressing is using the abrasive and bond absorbed laser energy to change the grinding wheel structure, thus to satisfy the request of grinding wheel geometric deviation. The laser absorption of superabrasive is an extremely important problem to laser truing and dressing of superabrasive grinding wheel. How to measure the laser absorption of superabrasive conveniently and economically is one of the rationale researches of laser truing and dressing superabrasives grinding wheel.This paper combines the experimental study with the numerical simulation, embarks from the heat transfer theory, bases on the lumped parameter method, then adopts the thermocouple sensor and data acquisition system to measure the superabrasive specimen thermoelectric potential before and after laser irradiating, afterwards transforms the thermoelectric potential into corresponding temperature and substitutes the temperature into absorption coefficient computation model, finally obtains the YAG laser absorption coefficient of MBD series artificial diamond and CBN series cubic boron nitride superabrasive. Analyzes the influence of laser average power,laser facual,heat-insulating material,laser irradiating frequency and so on to absorption coefficient, and discovers the influence rule and reason.Analysis the specimen's heat transfer way and heat convection form according to heat conduction theory, simultaneously, uses the lumped parameter method to measure the coefficient of heat convection, which is a new method for measuring the heat convection coefficient under special occasion. Establishes the three dimensional unstable heat transfer physical and mathematical model corresponded to entire experiment, carries on discretization to heat transfer model, substitutes the specimen absorption coefficient measured by experiment and its corresponding laser parameter into computational model, and makes program by APDL programming language and calculates the program in ANSYS software. Compares the calculated results with the experimental results, and examines and verifies the accuracy of measured results by analyzing the two results.