摘要
Fiber-reinforced silica ceramic matrix composites(SiO_(2) f/SiO_(2))have gained extensive attention in recent years for its applications in aeronautics field such as radar radome and window.However,the machining properties and mechanism of the material remain unclear.The features and mechanical properties of the material itself have a significant influence on both its machining characteristics and surface integrity.Thus,a full-factor grinding experiment is conducted using a 3 D orthogonal SiO_(2) f/SiO_(2) aiming to obtain its machining characteristics.The effects of grinding parameters and tools on the grinding force,surface roughness,and material damage type are investigated using a dynamometer,Scanning Electron Microscope(SEM),and Acoustic Emission(AE)analysis.The AE frequency band is analyzed,and a semi-analytical force model is established to study the difference between a single grain and wheel grinding.It was found that the changes in surface roughness correlate with the changes in grinding force,with fiber fracture being the main reason behind the increase in grinding force.Finally,the material removal mechanism was studied based on the AE analysis.It was found that the removal mechanism is fiber fracture dominated with matrix crack and debonding,and the primary sources of energy consumption are fiber fracture and friction.
基金
supported by the National Natural Science Foundation of China(Nos.51375333 and 51805365)。