Carbon Long Fiber Reinforced Aluminum Matrix Composites – Parameter Studies and Numerical Simulations of the Infiltration Process

Abstract

Carbon long fiber reinforced aluminum matrix composites are promising materials for applications in highly stressed lightweight structures. The use of continuous fibers as reinforcement structure offers the potential to increase the mechanical properties tremendously compared to the pure light metal alloy. The main problem for a more widespread utilization of metal matrix composites is that established manufacturing processes like gas pressure infiltration or squeeze casting are economically not attractive and cannot be upscaled for serial production. This paper shows the development of a production technique for the infiltration of carbon fiber yarns with aluminum using a conventional cold chamber die casting machine. Thereby the influence of the process parameters on the infiltration behavior is investigated. Of high importance are the plunger velocity and the temperature of the die, the melt, and the carbon fiber preform. Additionally, results of numerical simulations are presented and compared to the experimental findings.The demand for high-performance lightweight structures in transportation, machine building, and plant engineering is rising. Compared to conventional monolithic materials like polymers or light metals, continuous fiber reinforced composites can tolerate much higher loads and offer higher potential to improve mechanical properties than other reinforcements like discontinuous fibers or particles. The advantages of employing a metal matrix rather than the usual polymer one consist in higher stiffness and compressive strength as well as better elevated temperature capabilities. Therefore, continuous fiber reinforced metal matrix composites are ideally suited for applications in highly stressed lightweight structures, especially under additional thermal loads.The main problem hampering a more widespread utilization of metal matrix composites is the limited ability to produce such structures. Established manufacturing processes which are based on the melt infiltration of long fiber preforms are the gas pressure infiltration technique [1][2][3] and the squeeze casting process. [4,5] The gas pressure infiltration process allows the manufacture of highly complex components, but in economical aspects this process is not suitable for serial production because of the complex procedure and the extensive process cycle times. In contrast, squeeze casting is characterized by short cycle times, but the complexity of the preform and the part geometry is limited. In summary, these manufacturing processes are economically not attractive and cannot be upscaled for serial production.A good alternative for the fabrication process would be the high pressure die casting technology. It is characterized by short cycle times, high production rates, high level of automation, and the possibility to obtain thin-walled and complex part geometries because of the high melt velocity. However, previous studies for the manufacture of metal matrix composites by high pressure die casting are almost solely limited to the infiltrat...

Preparation and characterization of CVD-TiN-coated carbon fibers for applications in metal matrix composites

“…Al 4 C 3 formation at the fiber-matrix interface was completely suppressed if high pressure die casting (HPDC) method is applied for the infiltration of TiN-coated 3D-textile preforms with 226D alloy [32]. HPDC method is described in detail by Ballmes et al [33]. The reason is the remarkably shorter contact time with the molten metal compared with the GPI method.…”

Carbon Materials Reinforced Aluminum Composites: A Review

“…This method was widely used to fabricate aluminum matrix composites [2]. It can be used to fabricate many kinds of C/Al composites, such as continuous [23,[78][79][80][81][82][83] or short [37,60,84,85] carbon fibers/Al composites, VGCFs/Al composites [64,86], graphite/Al composites [66,[87][88][89], diamond/Al composites [90,91,92], etc.…”

“…With decades of research, the following methodologies have been proposed in order to address the above problems: (1) Optimizing the fabrication parameters such as applying an appropriate pressure to promote infiltration, limiting the high temperature contact time or using low temperature fabrication methods such as powder metallurgy [19,[22][23][24]. These methods are widely accepted, however, to be not enough to solve the problem of interfacial reactions.…”

Numerical analysis of non-isothermal infiltration process for fabricating magnesium matrix composite

“…Numerical tools such as finite element and finite difference methods are applied. Ballmes H.K et al [5] investigated preform infiltration based on the thermal conductivity and Darcy's law by finite element method (FEM). Qi L.H et al [6] simulated the temperature fields and the infiltration fields by the finite element method and the finite difference method, respectively.…”