硅锶复合孕育对含硼灰铸铁组织和性能的影响

用不同配比Si-Sr与Si-Fe复合孕育剂对含硼灰铸铁孕育处理,研究了Si-Sr复合孕育剂对其金相组织、力学性能及冶金质量指标的影响.结果表明:随Si-Sr孕育剂量的增加,含硼灰铸铁的抗拉强度、硬度随之递增.在Si-Sr含量为0.12%时抗拉强度达到峰值,σb=325 MPa;在Si-Sr含量为0.18%时硬度达到峰值,HB=273.此时,石墨主要为A型分布,共晶团细化,硼碳化物呈小块状,均匀分布在珠光体上,珠光体＞95%.当Si-Sr含量为0.12%时,含硼灰铸铁的成熟度RG=1.13,品质系数Qi=1.10,各项冶金质量指标达到最优.

Effect of Silicon-Strontium Compound Inoculants on Boron Gray Cast Iron

The Si-Sr and Si-Fe compound inoculants with different contents are used to treat the boron cast iron. With the addition of Si-Sr and Si-Fe, it is mainly studied the influence of the boron cast iron on its microstructure, mechanical properties and metallurgical quality index. Results show that the tensile strength and hardness increase gradually with increasing content of Si-Sr. When the ratio of Si-Sr is 0.12%, the maximum tensile strength is 325 MPa. Another the maximum data from hardness is 273 when the ratio of Si-Sr is 0.18%. Following the results, the shape of the graphite is A type and spread evenly. The finer eutectic cell is also obtained. The small block boron-carbide spreaded evenly in the pearlite is observed. The ratio of pearlite is more than 95%. When the ratio of Si-Sr is 0.12%, the RG is 1.13 and the Qi is 1.10. These show that the quality of the boron cast iron is optimum.