Fe-based multi-element active high-temperature solder for carbon fiber reinforced ceramic matrix composite

Abstract

The invention designs a Fe-based multi-element active high-temperature solder for a carbon fiber reinforced ceramic matrix composite. Stainless steel with low expansion coefficients is mainly used asa master alloy, melting point depressant elements are not added, and a liquid phase is obtained by a mode of eutectic reaction between Fe and carbon fibers in the solder in soldering so that the non-metallic carbon fibers can be rapidly wetted, a melting point of the solder, the soldering temperature and the service temperature of a joint can be improved favorably, and a brittle intermetallic compound formed by the melting point depressant elements can be avoided favorably; due to the fact that the stainless steel master alloy and an added refractory element Mo both have the advantages of being small in thermal expansion coefficient and high in heat resistance, an obtained soldering seam has the advantages of small in thermal expansion coefficient, resistant in oxidation corrosion and highin heat resistance, which is beneficial to reducing the thermal stress and improving the service temperature of the joint and improving the comprehensive performance of the joint; and the solder hasthe advantages of being low in price, high in soldering temperature, fast in wetting reaction, short in soaking time and high in room-temperature / high-temperature strength of the soldered joint.

Description

technical field [0001] The present invention relates to CMC high-temperature brazing filler metal, be specifically related to a kind of for CMC f / SiC and other carbon fibers (C f ) Fe-based multi-component active high-temperature brazing filler metal for reinforced ceramic matrix composites. Background technique [0002] The continuous fiber-reinforced ceramic matrix composite (CMC: ceramic matrix composite) obtained by implanting the continuous fiber-reinforced phase in the ceramic matrix combines the advantages of carbon fiber (high specific strength, large specific modulus, excellent high-temperature mechanical properties and thermal properties) and the advantages of SiC ceramics (high hardness, strong corrosion resistance, and strong oxidation resistance), it has become a relatively safe and practical method to improve the strength and toughness of ceramics. During the load-bearing and fracture process of ceramic matrix composites, the external force or energy can be ...

AI Technical Summary

Problems solved by technology

[0045] For carbon fiber-reinforced ceramic matrix composite base materials, the purpose of the present invention is to break through the existing Ag-based (such as Ag-Cu-Ti), Ti-based (such as Ti-Ni-Cu) solder with low melting point and poor heat resistance of the brazing seam. (The melting point is about 780-950°C), the primary technical problem, and the secondary problems of slow wetting of carbon fibers and too long holding time (such as Ni-based solder must be held for a long time to achieve isothermal solidification to increase the remelting temperature of the joint) , to design a kind of low-melting element, with cheap Fe as matrix element and active element (using Fe-C f The eutectic reaction realizes the wet carbon fiber, so Fe is the active element that wets the carbon fiber reinforced phase) Fe-based multi-active high-temperature solder (the basic alloy system is five-element Fe-Cr-Ni-Mo-Ti, Fe-Cr-Ni -W-Ti, etc. or six-element Fe-Cr-Ni-Mo-W-Ti, etc.)

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