The aramid fiber-reinforced composites(AFRC)can increase the durability of corresponding applications such as aerospace,automobile and other large structural parts,due to the improvement in hardness,heat build-up,wear...The aramid fiber-reinforced composites(AFRC)can increase the durability of corresponding applications such as aerospace,automobile and other large structural parts,due to the improvement in hardness,heat build-up,wear properties and green environmental protection.However,because of its complex multiphase structure and unique heterogeneity and anisotropy,the poor compression fatigue resistance and the incident surface fibrillation are inevitable.To improve the assembly precision of AFRC,mechanical processing is necessary to meet the dimensional accuracy.This paper focuses on the influence of contour milling parameters on delamination defects during milling of AFRC laminates.A series of milling experiments are conducted and two different kinds of delamination defects including tearing delamination and uncut-off delamination are investigated.A computing method and model based on brittle fracture for the two different types of delamination are established.The results can be used for explaining the mechanism and regularity of delamination defects.The control strategy of delamination defects and evaluation method of finished surface integrity are further discussed.The results are meaningful to optimize cutting parameters,and provide a clear understanding of surface defects control.展开更多
In order to study the dynamic characteristics of multilayer fiber reinforced plastic(MFRP)shaft,the coupling model of three-dimensional equivalent bending stiffness theory and transfer matrix method is established,and...In order to study the dynamic characteristics of multilayer fiber reinforced plastic(MFRP)shaft,the coupling model of three-dimensional equivalent bending stiffness theory and transfer matrix method is established,and the influence of thickness-radius ratio,length-radius ratio,layer angles,layer proportion,and stacked approaches on MFRP shaft dynamic characteristics is investigated.The result shows that the proposed coupling model has high accuracy in MFRP shaft dynamic performance prediction.The proportion of small-angle layers is the decisive factor of MFRP shaft natural frequency.With the increase of thickness-radius ratio and length-radius ratio,the natural frequency of MFRP shaft decreases.The natural frequency of MFRP shaft with the angle layers combination of±45°and±90°is smaller compared with the metal shaft no matter in simple/free boundary condition or simple/simple supported boundary condition.展开更多
基金supported by the National Natural Science Foundation of China(No.51975334)Key R&D Project of Shandong Province(No.2019JMRH0407)the Fundamental Research Funds of Shandong University Grant。
文摘The aramid fiber-reinforced composites(AFRC)can increase the durability of corresponding applications such as aerospace,automobile and other large structural parts,due to the improvement in hardness,heat build-up,wear properties and green environmental protection.However,because of its complex multiphase structure and unique heterogeneity and anisotropy,the poor compression fatigue resistance and the incident surface fibrillation are inevitable.To improve the assembly precision of AFRC,mechanical processing is necessary to meet the dimensional accuracy.This paper focuses on the influence of contour milling parameters on delamination defects during milling of AFRC laminates.A series of milling experiments are conducted and two different kinds of delamination defects including tearing delamination and uncut-off delamination are investigated.A computing method and model based on brittle fracture for the two different types of delamination are established.The results can be used for explaining the mechanism and regularity of delamination defects.The control strategy of delamination defects and evaluation method of finished surface integrity are further discussed.The results are meaningful to optimize cutting parameters,and provide a clear understanding of surface defects control.
文摘In order to study the dynamic characteristics of multilayer fiber reinforced plastic(MFRP)shaft,the coupling model of three-dimensional equivalent bending stiffness theory and transfer matrix method is established,and the influence of thickness-radius ratio,length-radius ratio,layer angles,layer proportion,and stacked approaches on MFRP shaft dynamic characteristics is investigated.The result shows that the proposed coupling model has high accuracy in MFRP shaft dynamic performance prediction.The proportion of small-angle layers is the decisive factor of MFRP shaft natural frequency.With the increase of thickness-radius ratio and length-radius ratio,the natural frequency of MFRP shaft decreases.The natural frequency of MFRP shaft with the angle layers combination of±45°and±90°is smaller compared with the metal shaft no matter in simple/free boundary condition or simple/simple supported boundary condition.
