硬质合金球头铣刀介观几何特征参数优化

发布时间：2018-03-19 22:40

本文选题：钛合金　切入点：球头铣刀　出处：《哈尔滨理工大学》2017年硕士论文　论文类型：学位论文

【摘要】：钛合金因具有强度高、耐热性好等优良性能而在航空航天、汽车、冶金、造船以及医疗等领域得到了广泛应用。同时钛合金作为典型的难加工材料,导热系数小、化学活性高易导致刀具磨损。针对钛合金的加工特点,本文将介观几何特征(表面微织构和刃口钝圆半径)引入到硬质合金球头铣刀,探讨了介观几何特征对球头铣刀铣削钛合金切削性能的影响规律,并对介观几何特征参数进行优化及实验验证。首先,依据微织构的形貌特征,建立了微坑织构和沟槽织构的数学模型;依据斜角切削模型建立了具有介观几何特征的球头铣刀的切削力和切削温度模型,研究了介观几何特征对切削力和切削温度的影响。其次,利用有限元软件Deform,对具有不同介观几何特征的球头铣刀铣削钛合金进行仿真分析。得到了微坑织构、横向沟槽织构、纵向沟槽织构、正交沟槽织构以及刀具刃口钝圆半径对切削力、切削温度和刀具表面应力的影响规律。再次,以仿真参数为依据,设计正交实验采用多元非线性回归,构建切削力和切削温度的预测模型。采用遗传算法,以最小切削力和最低切削温度为优化目标,对球头铣刀介观几何特征参数进行了优化,得到了最优的微坑织构的直径,深度,微坑织构间的距离,距离切削刃的距离及刃口钝圆半径。最后,采用激光加工设备,制备具有不同介观几何特征的球头铣刀;建立介观几何特征球头铣刀铣削钛合金实验平台,验证了切削力模型及优化结果的正确性,同时分析了介观几何特征参数对摩擦系数的影响规律。
[Abstract]:Titanium alloys have been widely used in aerospace, automobile, metallurgy, shipbuilding and medical treatment because of their high strength and good heat resistance. According to the machining characteristics of titanium alloy, the mesoscopic geometry (surface microtexture and blunt radius of the cutting edge) is introduced into the cemented carbide ball end milling cutter. The effect of mesoscopic geometry on the cutting performance of titanium alloy in milling with ball end milling cutter is discussed, and the parameters of mesoscopic geometry are optimized and verified by experiments. The mathematical models of microcrater texture and groove texture were established, and the cutting force and cutting temperature model of spherical end milling cutter with mesoscopic geometry were established according to the oblique cutting model. The effect of mesoscopic geometry on cutting force and cutting temperature is studied. Secondly, the microcrater texture and transverse groove texture are obtained by means of finite element software Deform. the milling titanium alloy with different mesoscopic geometry characteristics is simulated and analyzed. The effects of longitudinal groove texture, orthogonal groove texture and blunt radius of cutting edge on cutting force, cutting temperature and tool surface stress are studied. Thirdly, based on the simulation parameters, the orthogonal experiment is designed with multivariate nonlinear regression. The prediction model of cutting force and cutting temperature is constructed. With the minimum cutting force and the minimum cutting temperature as the optimization targets, the mesoscopic geometric characteristic parameters of the ball end milling cutter are optimized, and the optimum diameter of the microcrater texture is obtained. The depth, the distance between the microcrater texture, the distance from the cutting edge and the blunt radius of the cutting edge. Finally, the ball end milling cutter with different mesoscopic geometry characteristics was prepared by laser processing equipment. The experimental platform for milling titanium alloy with mesoscopic geometric feature ball end milling cutter was established to verify the correctness of the cutting force model and the optimization results. At the same time, the influence of mesoscopic geometric characteristic parameters on the friction coefficient was analyzed.
【学位授予单位】：哈尔滨理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TG714

【相似文献】