节流阀硬质合金抗氧化性能研究

Study on Antioxidant Performance of Throttle Valve Cemented Carbide

针对节流阀在冲蚀过程中硬质合金存在氧化现象,对柱塞和笼套硬质合金进行氧化试验,对氧化前后组织进行扫描电镜观察,并对其氧化过程进行热力学以及动力学分析,以揭示氧化现象对硬质合金气体冲蚀所造成的影响。结果表明:两种硬质合金氧化时,会有缺碳相Co_6W_6C以及CO_2和CO气体的生成。两种合金氧化速度都随温度升高而急剧上升,氧化增重曲线近似为直线。柱塞和笼套硬质合金的氧化反应激活能分别为210.281、297.093 kJ/mol,因此笼套硬质合金相比柱塞硬质合金具有更好的抗氧化性。

In view of cemented carbide appearing oxidation in the process of erosion of throttle valve, the oxidation experiment of plunger cemented carbide and cage cemented carbide was carried out. The microstructure of the samples before and after oxidation was observed by SEM. The thermodynamics and kinetics analysis in the process of oxidation was analyzed. The effects of oxidation phenomenon on the gas erosion of cemented carbide were researched. The results show that when two kinds of cemented carbide are oxidated, lack of carbon phase-Co6W6C, CO2 and CO gas generate. Both of the alloys oxidation rate increase sharply with temperature increasing. The oxidation mass gain curve is approximate to linear. The oxidation reaction activation energy of plunger cemented carbide and cage cemented carbide is 210.281 kJ/mol and 297.093 kJ/mol, respectively, so the cage cemented carbide has better oxidation resistance compared with plunger cemented carbide.