Process for preparing composite materials with self radial gradient by in situ crystallization

Abstract

The invention discloses a process for preparing self-generated radially gradient composite materials by an in-situ crystallization method, which belongs to the field of composite material preparation. Specifically: after remelting the self-generated composite material, the remelting temperature is 50-150°C above the liquidus line, pouring it into a SiC casting mold; generating an induced high-frequency magnetic field through a high-frequency power supply and a cylindrical axisymmetric induction coil, and then With the reduction of the power supply of the induced high-frequency magnetic field by 7Kw~2Kw, the preheating temperature of the casting mold is increased linearly by 30℃~300℃; the temperature measuring device of the single-channel SiC casting mold is used to monitor the temperature of the self-generated composite material. When the temperature of the self-generated composite material drops close to the eutectic temperature of the material, the high-frequency magnetic field is turned on, and the action time is 4s-32s. When the temperature of the self-generated composite material rises close to the liquidus temperature, the effect of the high-frequency magnetic field is terminated; finally, the self-generated composite material Solidification molding in SiC casting mold. The invention significantly increases the effective action time of the high-frequency magnetic field and improves the yield of materials.

Description

technical field [0001] The invention relates to a process for preparing composite materials, especially a process for preparing self-generated radial gradient composite materials by combining in-situ crystallization and induced high-frequency magnetic field separation technology, which belongs to the field of composite material preparation . Background technique [0002] In the in-situ composite method of particle-reinforced metal matrix composites, in-situ crystallization composites are formed by in-situ crystallization of reinforced particles, and there are no existing reinforced particles in the composite material melt at high temperature, so the prepared composite materials can be remelted and reused. Compared with composite materials obtained by other in situ preparation methods, the stability has more significant advantages. The principle of separating non-metallic phases using the significant conductivity difference between the metal melt and the non-metallic heterog...

AI Technical Summary

Problems solved by technology

Because this method reasonably controls the application timing of the induced high-frequency magnetic field, and at the same time the casting material used has a slow heat dissipation and is multi-channel in parallel, it is difficult to control the heating effect of the induced high-frequency magnetic field on the composite material in the preparation process , causing part of the reinforcement to re-melt into the matrix, resulting in an extremely unstable gradient effect of the self-generated composite material