硼对低合金灰铸铁性能的影响

Effect of Boron on Properties of Low Alloy Gray Cast Iron

硼在灰铸铁中能够形成硬质相的硼碳化物,当硼加入量控制在0.02%~0.10%时,可显著增加灰铸铁的耐磨性能。以低合金灰铸铁为研究对象,通过改变加入无水硼砂的含量来控制铸铁中硼的含量(0~40 ppm),通过直读光谱仪、光学显微镜、万能拉伸试验机等设备,对其组织和性能进行分析。研究结果表明,微量的硼使得灰铸铁金相中存在少量的铁素体,对于模数类似于Y50试块时,硼由7 ppm提高至20 ppm时,其抗拉强度降低15 MPa、硬度降低5.5 HBW。

Consult data to discover,at present people mainly study to use boron to increase carbide in gray cast iron to increase wear resistance of cast iron,among which the amount of boron is 0.02%to 0.1%,but the influence of trace boron on cast iron property belongs to blank research.In this paper,low-alloy gray cast iron was taken as the research object,and the content of cast iron was controlled boron(0~40 ppm)by changing the content of Anhydrous borax added.The structure and properties of cast iron were analyzed by using direct reading spectrometer,optical microscope,universal tensile testing machine and other equipment.The results show that a small amount of ferrite exists in the metallofacies of gray cast iron due to a small amount of boron.When the modulus of the casting is similar to Y50 block,the tensile strength decreases by about 5%and the hardness decreases by about 3%when boron is increased from 7 ppm to 20 ppm.