Study On Vacuum Suction Casting And Formation Of Short Carbon Fiber Aluminum-based Alloy Blades

The short carbon fiber aluminum-based alloy has the characteristics of light weight and excellent performance,and has broad application prospects in the field of transportation engineering,especially in the manufacturing direction of aero engine blades,and is the material of choice for advanced aero blades.The vacuum suction casting process can better adapt to the formation and preparation of more complex composite aviation blade parts due to its excellent casting performance and flexible design performance.Therefore,it is of great research significance to explore the forming and forming properties of vacuum suction casting of short carbon fiber aluminum-based alloy blades,and to provide a new idea and method for the production of high-performance composite advanced aviation blades by vacuum suction casting.This paper mainly proposes a vacuum suction casting and pressure forming process suitable for short carbon fiber aluminum-based alloy blades.Under this process condition,the main parameters during preparation are studied: the parameters of short carbon fiber and the parameters of improving the interface on the blade performance.Impact.First,according to the forming requirements of composite material blades,a vacuum suction and pressure composite forming process is proposed,and a vacuum suction blade type casting mold and a cold pressure shaping mold suitable for this process are designed to complete the aviation blade forming experiment.Secondly,the finite element method was used to analyze the short carbon fiber parameters: the effect of short carbon fiber length and short carbon fiber content on the forming properties of short carbon fiber aluminum-based alloy blades.Finally,blade performance testing experiments were performed to analyze the parameters that improve the bonding interface between carbon fiber and aluminum-based alloys: the effects of the addition of trace elements Mg and Si,and the pressure on the blade forming performance.Optimized process parameters for short carbon fiber aluminum-based alloy blades for vacuum suction casting and pressure-compression forming were obtained.After research on the formation and formation of short carbon fiber aluminum-based alloy blades,the following conclusions were reached:(1)By designing the blade casting mold and subsequent pressure mold,the vacuum suction and compression composite process can be innovatively applied to the preparation of short carbon fiber aluminum-based alloy blades.On the part,the composite material blade prepared by using this process and the forming mold has a complete forming shape,stable dimensions and high accuracy,which verifies the feasibility and rationality of the process scheme.(2)The parameters of short carbon fiber including the length of short carbon fiber and the content of short carbon fiber on the blade performance were analyzed.Firstly,the method of macro and micro numerical analysis was used.It was found that as the carbon fiber content increased,the tensile strength of the material increased but the elastic modulus decreased;as the length of the short carbon fiber increased,the plastic strength of the part gradually decreased and increased.After 5mm,it reached a steady trend.Therefore,according to the results of numerical analysis,a short carbon fiber reinforced aluminum-based alloy blade prepared with a short carbon fiber length of 1 mm and an added content of 3wt% carbon fiber should be selected.The obtained blade performance can better meet the working requirements,and has been verified through experiments.(3)Two methods to improve the bonding interface between carbon fiber and aluminum alloy matrix were analyzed: the effects of adding trace elements Mg and Si and pressing on the performance of the formed blade parts.Mechanical properties of the blades prepared with the contents of trace elements Mg and Si(Mg and Si are 0.1wt%,0.2wt%,0.3wt%,respectively)and the subsequent pressure pressure(2MPa,4 MPa,6 MPa,8 MPa)After inspection and analysis of electrical and electrical properties,it was concluded that the trace elements Mg and Si can both improve the mechanical properties of carbon fiber aluminum-based alloy blades,and Mg has better blade mechanical properties than Si.Appropriate pressure can improve the mechanical properties of carbon fiber aluminum-based blades,but the effect on improving electrical performance is not obvious.When the pressure is 4 MPa,the blade performance improvement is the best.The short carbon fiber reinforced aluminum-based composite blades are prepared.After pressing,the tensile strength reached 334 MPa,which was 52.69% higher than that of unpressed blade parts.At this time,the micro hardness was 133.3 HV,and the resistivity was 22 μΩ · mm.