摘要
以钨粉、钴粉、炭黑、有机碳为原料,研究了W、Co和C混合粉末在放电等离子烧结系统中碳化反应快速烧结制备WC-6%Co硬质合金的原位碳化烧结工艺。系统研究了配碳量、烧结温度、保温时间和加压方式对硬质合金的显微组织结构和性能的影响。结果表明:碳含量为理论值1.2倍时合金物相为纯WC和Co相,无脱碳相,也未发现游离碳;烧结温度在1 250℃时,WC晶粒均匀且无异常长大;保温时间设置为5 min时,合金性能较为理想;在W、Co和C混合粉末烧结初期施加30 MPa压强,待温度升到800℃时再将压强加到50 MPa制备的合金孔隙较少,致密化程度高。本工艺较传统制备工艺具有流程短,成本低的特点,可为硬质合金工业生产提供参考。
Using tungsten powder, cobalt powder, carbon black and organic carbon as raw materials, the fabricating process of in-situ carbonization and fast sintering WC-6 %Co cemented carbides with the spark plasma sintering system is investigated. The effects of carbon content, sintering temperature, holding time and the way of applying pressure to the graphite jig are analyzed systematically. The results reveal that there are WC and Co phases exist in as-prepared alloys, the decarbonization phase and free carbon are absent when the initial carbon content is 1.2 times of the theoretical value. The grains of WC are uniform and the abnormal growth is absent when sintering temperature is 1 250 ℃. The mechanical properties of cemented carbides are the optimal when the holding time is 5 rain. The porosity of the alloy is small when applying 30 MPa on the early stage of the sintering process and rising to 50 MPa when the temperature reaches to 800 ℃. Compared with the traditional process, the proposed route in this paper is shorter and the cost is lower. The technology can be applied to the production of cemented carbides directly.
出处
《中国钨业》
CAS
北大核心
2016年第6期13-17,34,共6页
China Tungsten Industry
基金
国家自然科学基金项目(KKGA201251011
51464013)
云南省科技厅面上项目(2015FB127)
昆明理工大学分析测试基金(2016P20151130003)
江西省科技厅科技支撑项目(20151BBE50002)
江西省教育厅青年项目(GJJ150648)
江西理工大学重点项目(NSFJ2015-K18)
关键词
原位碳化快速烧结
碳含量
烧结工艺
组织结构
性能
In-situ carbonization and rapid sintering
carbon content
sintering process
microstructure
mechanicalproperty
