Production process of wire drawing hard alloy die with gradient varying performance

Abstract

The production process of wire drawing hard alloy die includes compounding material, molding to form, pre-sintering and dewaxing, sintering and carbonization. During the carbonization, the mixture of Al2O3, graphite grain and carbonate and / or bicarbonate in certain proportion is used as carbonizing agent, the carbonate and / or bicarbonate is high temperature decomposed into CO2, CO2 is further reacted with graphite grain into active CO gas capable of entering into liquid phase and reacting to produce WC, and the inward immigration of CO speeds the formation of the gradient structure inside the alloy. The said carbonization procedure has relatively low temperature, short period and relatively thick surface layer without eta phase, and the alloy has obvious gradient adhering phase structure, high comprehensive mechanical performance, high average bending strength and high average hardness.

Description

technical field [0001] The invention belongs to a production method of a cemented carbide wire drawing die in the field of wire drawing die production, in particular to a production method of a cemented carbide wire drawing die in which the mechanical properties of the die body are distributed in a gradient from outside to inside. Background technique [0002] The internal and external mechanical properties and metallographic structure of traditional cemented carbide molds (that is, standard cemented carbide molds) are consistent. This type of mold often has a contradiction between high hardness, wear resistance and toughness that is difficult to reconcile, namely When reducing the content of cobalt (Co) in the alloy to increase its hardness and wear resistance, the toughness of the alloy body will decrease accordingly, otherwise it will affect its hardness and wear resistance. In addition, for cemented carbide wire drawing dies with consistent metallographic and mechanical ...

AI Technical Summary

Problems solved by technology

[0004] The solution of the present invention is to address the defects of the background technology such as long carburizing treatment time, simple carburizing agent composition, low reactivity, and low carburizing treatment efficiency, and use Al-containing 2 o 3 , graphite particles and carbonate or / and bicarbonate mixed powder as carburizing agent

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