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由于碳纤维增强树脂基复合材料(Carbon fiber reinforced plastic,CFRP)宏观上呈现非均质、各向异性,细观上表现为纤维和树脂的特殊混合形态,导致其制件加工过程中极易产生分层、开裂等损伤,严重影响其制件的加工精度及承载性能。研究CFPR加工损伤产生机理并以此降低加工损伤是提高其加工质量的关键。本文基于宏观各向异性本构、Hashin失效起始准则及损伤演化,建立了可实现任意纤维角度单向板连续动态切削过程仿真分析的直角切削有限元模型,分析了任意纤维角度CFRP单向板连续切削过程面下损伤,得到了纤维角度、切削参数、刀具结构对面下损伤深度的影响规律。具体结果:纤维角度为影响面下损伤的主要因素,随纤维角度增大,切削力增大同时面下损伤深度也明显增加;面下损伤的主要原因为切削力过大导致的基体破坏及扩展;对于135°单向板面下损伤深度随刀具前角增大呈先增大后减小的趋势。
As carbon fiber reinforced plastic (CFRP) macroscopically shows heterogeneity and anisotropy, the microscopic view shows the special mixed morphology of fiber and resin, which leads to the easy production of CFRP Layer, crack and other damage, seriously affecting the processing accuracy and bearing capacity of its parts. To study the mechanism of CFPR processing damage and to reduce the processing damage is to improve the processing quality of the key. Based on the macroscopic anisotropy constitutive model, Hashin failure initiation criterion and damage evolution, a finite element model of right angle cutting was established to simulate continuous dynamic cutting process with one-way plate at any fiber angle. The CFRP one- Under continuous cutting process, the influence of fiber angle, cutting parameters and tool structure on the depth of damage was obtained. Specific results: The fiber angle is the main factor that affects the under-surface damage. As the fiber angle increases, the cutting force increases while the depth of the under-surface damage also increases obviously. The main reason of under-surface damage is the destruction and extension of the matrix caused by the excessive cutting force For the 135 ° unidirectional plate surface, the damage depth firstly increases and then decreases with the increase of tool rake angle.