Study On Technology And Performance Of Low Temperature Reducing Recycled Waste Carbide By Liquid Carbon Source

With the growing shortage of primary resources,large quantity of scrap in industry and daily live and need to be recycled urgently,people began to pay attention to recycling and sustainable development.As an important strategically metal,secondary recycling of the tungsten are paid much attention to in many countries.In present paper,a recycling technique,the oxidization+reduction process,of tungsten alloy scrap was investigated and proved to be an less energy consumpt,an effective and simple method.Renewable carbide show excellent mechanical properties.The scraps of WC-Co alloys were washed and subsequently opened the fire door and oxidized for3hours at800℃,the oxide could be obtained without over-grown up,and particle size is moderate,followed by milling. After milling the oxide powders with carbon,obtained the precursor powder at550℃nitrogen atmosphere by15min/boat speed.The preparation process of WC-Co composite powders were optimized by using the method of orthogonal design.The carbon content,oxygen content,grain morpholog and composition of the WC-Co composite powders were also determined by using the gasometric method,optical microscope,X-ray diffraction(XRD),scanning electron microscopy (SEM) and so on. At the same time, the range analysis of the experimental results were performed by using the range analysis method and the influence of various factors on the properties of WC-Co composite powders were obtained. Experimental results show that:The temperature of reduction and carbonization,feeding rate and flow rate of hydrogen have an important impact to the experimental results.The carbon, and oxygen content standards and good regeneration of powder grain morphology were prepared by using the method of orthogonal design.The temperature of1000℃,feeding rate of30min/boat and hydrogen velocity of flow at2.0m3·min-1were the best renewable tungsten carbide cobalt powder.The powder particle size was0.3-0.6μm,the content of total carbon was5.58wt%,the content of free carbon was0.188wt%,and oxygen content was0.22wt%.Renewable Carbide was prepared after compression,expelling glue and gas pressure sintering(GPS) under a temperature of1420℃.The grain size of regeneration was1μm. In this article good properties of renewable carbide was prepared,and grain was finer than the original waste alloy.