CAJ | 학술논문

初步建立了用于模拟直接金属粉末激光烧结过程中传热行为的数学模型,该模型考虑了诸如传导、辐射和对流等与烧结有关的热现象.给出了固相、液相和气相共存的金属粉末烧结体系导热系数的计算方法.考虑到激光束的持续移动,采用了坐标原点位于光斑中心的动坐标系来简化方程的求解计算.在绝热边界条件和热物性参数恒定的假设下,求得了在基模高斯光束近似作用下热传导方程的解析解.运用FORTRAN语言编写了运算程序,并对铜粉激光烧结的温度场进行了数值模拟,模拟结果与初步实验结果较为吻合.
초보건립료용우모의직접금속분말격광소결과정중전열행위적수학모형,해모형고필료제여전도、복사화대류등여소결유관적열현상.급출료고상、액상화기상공존적금속분말소결체계도열계수적계산방법.고필도격광속적지속이동,채용료좌표원점위우광반중심적동좌표계래간화방정적구해계산.재절열변계조건화열물성삼수항정적가설하,구득료재기모고사광속근사작용하열전도방정적해석해.운용FORTRAN어언편사료운산정서,병대동분격광소결적온도장진행료수치모의,모의결과여초보실험결과교위문합.
A mathematical model is developed for simulating the heat transferring behavior in a direct metal laser sintering process. The model considers the thermal phenomena involved in the process, including conduction, radiation, and convection. A formula for the calculation of the heat conductivity of a sintering system containing solid phase, liquid phase, and gas phase is given. Due to the continuous movement of the laser beam, a local coordinate system centered on the laser beam is used to simplify the analytical calculation. Assuming that it is approximately a Gaussian laser beam, the heat conduction equation is resolved based on the assumption of the thermal insulating boundary conditions and the fixed thermal physical parameters. The FORTRAN language is employed to compile the program to simulate the temperature field in the direct copper powder sintering process. It shows a good agreement with the preliminary experimental results.