Silicon carbide particle reinforcement aluminum-based composite for train brake disc and preparation method

Abstract

Disclosed are a silicon carbide particle reinforcement aluminum-based composite for a train brake disc and a preparation method. The composite includes the following components of, by mass percentage, 15-25% of SiC particles, 18-24% of Si, 0.6-3.5% of Mg, 0.15-0.35% of Zr, 0.12-0.45% of Sc, and the balance Al and unavoidable impurities. According to the preparation method, SiC, Mg, Si, Zr and Sc with the particle size being 10-15 [mu]m are added into molten aluminum in the form of intermediate alloy, SiC with the particle size being 15-25 [mu]m is added into the molten aluminum in the form of particles, and thus the silicon carbide particle reinforcement aluminum-based composite is obtained. The SiC thin particles are added in the form of Mg-SiC, so that the problems of uniform dispersing difficulty of silicon carbide particles in a matrix and poor interface bonding are effectively solved, the particle reinforcement effect is fully played, and the toughness of alloy is improved. Meanwhile, transitional element zirconium and rare earth element scandium are added to replace titanium fine grains, the roughness and heat resistance of the aluminum-based composite are remarkably improved, and occurrence of heat fatigue cracks is restrained. In addition, the added rare earth scandium has a good modification effect on the interfacial compatibility of the silicon carbide particles and aluminum alloy.

Description

technical field

[0001] The present invention relates to a silicon carbide particle-reinforced aluminum-based composite material for train brake discs and a preparation method thereof, in particular to a high-strength, heat-resistant and impact-resistant silicon carbide particle-reinforced aluminum-based composite material for train brake discs. The material and the preparation method thereof belong to the field of braking devices for rail transit. Background technique

[0002] In the field of rail transportation technology, the material of the brake disc is extremely critical for the effective braking of the locomotive. During emergency braking of high-speed trains, the huge thermal load of the brakes causes a large temperature gradient on the brake discs, which generates thermal stress and may lead to thermal cracks. The material of the brake disc is required to have good thermal fatigue resistance, the friction coefficient of the friction pair under various working condit...

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