Surface roughness modeling for grinding of Silicon Carbide ceramics considering co-existence of brittleness and ductility
Surface roughness modeling for grinding of Silicon Carbide ceramics considering co-existence of brittleness and ductility
复制标题
考虑脆性和延展性共存的碳化硅陶瓷磨削表面粗糙度建模
DOI：
10.1016/j.ijmecsci.2017.07.061
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发表时间：
2017-11-01
影响因子：
7.3
通讯作者：
Liang, Steven Y.
中科院分区：
文献类型：
--
作者：
Wu, Chongjun;Li, Beizhi;Liang, Steven Y.
由于磨粒分布的随机性和材料性质的多样性，磨削表面粗糙度一直难以预测，对于脆性材料更是如此。在脆性材料的磨削中，由于材料的脆性和硬性，材料将以延性和脆性两种模式被去除，这给表面粗糙度的建模带来了困难。因此，本文提出了一种新的脆性材料表面粗糙度模型，该模型考虑了加工诱发延性和脆性的共存。通过假设单个磨粒的切屑厚度符合该分布，将使用瑞利分布函数对磨粒的随机性进行建模。同时采用临界切屑厚度模型，综合考虑材料性能和工艺参数，对单个磨粒进行延性磨削和脆性磨削的划分。因此，可以通过对瑞利分布函数的积分计算来获得延性模式磨削的概率。采用压痕断裂力学中的磨削损伤模型来模拟脆性表面粗糙度。通过一系列碳化硅磨削实验，对表面粗糙度和切屑厚度模型进行了标定和验证。结果表明，模型预测结果与实验结果吻合较好，韧性表面粗糙度远小于脆性表面粗糙度。因此，脆性材料的表面粗糙度建模可以考虑加工运动学、磨料拓扑和工艺参数所决定的脆性和塑性的共存，以及磨削引起的表面损伤。此外，在较高的砂轮转速或较低的切屑厚度下，延性占主导地位的磨削可以在较低的损伤水平下改善表面粗糙度。(C)爱思唯尔有限公司发布的2017年。
Ground surface roughness is always hard to be predicted due to the random distribution of abrasive grits and various materials properties, especially for brittle materials. In grinding of brittle materials, because of the brittle and hard nature, the material will be removed in both ductile and brittle modes, which make the modeling of surface roughness difficult. Therefore, this paper is intended to propose a new surface roughness model for brittle materials by considering the co-existing of machining-induced ductility and brittleness. A Rayleigh distribution function will be used to model the randomness of abrasive grits by assuming that the chip thickness for a single grit conforms to this distribution. In the meanwhile, the critical chip thickness model, considering both the materials properties and process parameters, will be adopted to divide the ductile and brittle grinding for a single grit. Thus, the probability for ductile mode grinding can be obtained through integral calculation of the Rayleigh distribution function. The grinding damage model from the indentation fracture mechanics is used to model the brittle surface roughness. The surface roughness and chip thickness model was calibrated and validated through a series of experiments on grinding of Silicon Carbide. The results show that the model predictions have a good match with the experimental results and the ductile surface roughness is much smaller than the brittle mode. Therefore, it can be concluded that the surface roughness modeling of brittle materials could benefit from considering the co-existence of brittleness and ductility governed by the machining kinematics, abrasive topology and process parameters, as well as the grinding induced surface damages. Moreover, the ductility-dominant grinding, under a higher wheel speed or lower chip thickness, can help to improve the surface roughness with a lower level of damage. (C) 2017 Published by Elsevier Ltd.