Study Of Mechanical And Thermal Physical Properties Of Carbon Fiber P100Reinforced Aluminum Composite Materials

In this paper, pitch based carbon fiber P100reinforced aluminum alloycomposites (P100/Al) was fabricated by the squeeze-casting technology. Themicrostructure and properties of pitch based carbon fiber, and the effect of carbonfiber content, matrix alloy and process parameters on microstructure (especiallyinterface state), mechanical properties and thermal physical properties by XRD,transmission electron microscope (TEM), scanning electron microscope (SEM),Laserflash thermal analyzer，Heating automatic analyzer.Pitch based carbon fiber P100had high graphitization degree, low pore ratio,big crystallite size La and thickness of the crystallite stack Lc was big. In addition,the relationship of graphitization degree, porosity ratio and the thermal conductivityof pitch based carbon was set up.Pitch based carbon fiber P100reinforced aluminum composites fabricated bythe squeeze-casting technology had no defect. However, low volume fraction ofcarbon fiber did not distribute uniformly. With an increase of fiber content, carbonfibers arranged more closely, and the elastic modulus and bending strengthincreased.The result of thermal conductivity measure of the composites materials showedthat while the fiber content increased, the longitudinal thermal conductivity firstlygrew up, than declined, which could not comply with the mixed law, and thetransverse conductivity declined, which Kingery model could predict better. Thecomposites had higher thermal conductivity which could have matrix with higherthermal conductivity, and when in the annealing state, rather than the die castingstate.Multiple factors effected thermal expansion of P100/Al composite materials.With an increase of temperature, the longitudinal thermal expansion coefficientfirstly grew up, than declined, and the transverse thermal expansion coefficientincreased. With increased volume fraction, thermal expansion coefficient reduced.The effect of matrix was different when carbon fiber content was different. Thecomposites had lower thermal expansion in the Annealing state than in the diecasting state. Van Fo Fy model could better predict thermal expansion coefficientalong the fiber direction; Schapery model could better predict vertical fiber directionthermal expansion coefficients.