Method of synthesizing metal -based composite material by melt reaction in coupling magnetic field and ultrasonic field

Abstract

A method of synthesizing metal matrix composite material by melt reaction in coupling magnetic field and ultrasonic field comprises: adjusting metal-base melt to the onset reaction temperature after refining, then adding reactants which generate reinforced particles by in-situ synthesis reaction with melt, keeping the reacted melt stand until it is cooled to casting temperature after the reaction, and then casting. Magnetic field and high-energy ultrasonic field are exerted simultaneously during the reaction. The magnetic field can be high-power pulse magnetic filed, high-frequency oscillating magnetic field or low-frequency alternating magnetic field. The metal matrix composite material produced by the above-mentioned method exhibits that reinforced particles are much finer, more uniformly distributed, and fit with metal matrix better.

Description

TECHNICAL FIELD[0001]The invention relates to the technical field of novel composite material synthesis, in particular to a novel method of synthesizing particle reinforced metal matrix composite material by in-situ melt reaction in coupling electromagnetic field and ultrasonic field.BACKGROUND ART[0002]Particle reinforced metal matrix composite material has a wide application prospect in the fields of advanced electric and electronic devices, aviation spacecrafts, machine, bridge tunnel engineering, etc. because of its excellent mechanical properties and physical and chemical properties owing to its composite structure and has been one of research hotspots of metal matrix composite material in recent years. Presently, in-situ reaction synthesis method is the primary method of preparing particle reinforced metal matrix composite material, its principle is that alloying elements or compounds which can generate second phase are added in metal matrix melt to produce in situ particle re...

AI Technical Summary

Benefits of technology

[0012](3) The magnetic field 4 can be selected as low-frequency stirring magnetic field coupling with power ultrasonic field if the requirements on size and distribution of particles of the composite material are lower. Especially when the amount of metal to be treated is large enough to be in tons, because of the limitations of present high-frequency oscillating magnetic field and high-power pulse magnetic field, coupling low-power stirring magnetic field and high-energy ultrasonic field also can be adopted to obtain an ideal effect. The principle lies in high-energy ultrasonic field generating cavitation effect and acoustic streaming impact in the melt, wherein cavitation effect controls the aggregation of particles, and acoustic streaming impact plays a role of stirring in micro area; the exerted low-frequency stirring magnetic field 4 performs electromagnetic stirring to the whole bath, so the ultrasonic stirring effect is more obvious, and the local effect or concentrated effect of ultrasonic treatment can be controlled.

[0030]The invention has the following advantages compared with the prior art:

[0031](1) Because the composite material is synthesized by coupling magnetic field and ultrasonic field, the coupling of magnetic field and ultrasonic field causes particles to be finer and uniformly distributed;

[0032](2) Ultrasonic wave oscillating stirring and electromagnetic stirring improve the dynamic conditions of synthesis, and particle phase fits with metal matrix interface better; and

[0033](3) Magnetochemistry cooperates with sonochemistry to improve the thermodynamic conditions of in-situ reaction, which accelerates the in-situ reaction speed and controls the growth of particle phase.

Problems solved by technology

However, the technique has a series of problems of difficult control of reaction process, easy growth even aggregation of particle phase, and uneven distribution.

However, the effect of exerting single electromagnetic field or ultrasonic field on synthesizing particle reinforced composite material by in-situ reaction is unsatisfied.

When exerting single magnetic filed, the action intensity of the magnetic field in metal decays exponentially due to insurmountable skin effect of the electromagnetic field in metal melt, and the effective depth of the electromagnetic field acting in the melt is limited, especially when employing a large-volume bath or an electromagnetic field with higher frequency, the difference of the effect of the electromagnetic field in the melt is significant, namely, the effect of the electromagnetic field in the melt shows severe nonuniformity, the effect of the electromagnetic field is weak in the central area and strong at the edge area.

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