【摘要】 目前，基于改性的新型无机粘结剂砂已成功运用于铸铝件的生产，同时也满足了行业对环保的高要求。但新型无机粘结剂砂用于铸铁件的生产，还存在较多问题，如常温强度偏低，尤其是高湿度环境下的强度低，以及高温残留强度高等，有必要进行进一步的研究。为此，本文经前期初步筛选试验，最终选用一种新型无机粘结剂，考察了诸多因素对芯砂试样强度的影响。结果表明，在一定范围内，粘结剂及促硬剂用量越大，芯砂常温强度和高温残留强度越高；随模具温度升高，芯砂常温强度先升后降，而残留强度受模具温度影响较小；原砂对芯砂强度影响最大，球形陶瓷砂良好的流动性及其物化特性提高了常温强度，但不利于残留强度的降低，而采用硅砂，其残留强度较低；经正交试验优化的工艺是：使用50/100目硅砂，粘结剂加入量2.4%，促硬剂为粘结剂的50%，模具温度180℃，芯砂24 h常温强度为2.71 MPa,98%RH下的强度为2.39 MPa,800℃残留强度为0.13 MPa。更多还原

【Abstract】 In recent years, new inorganic binder sand based on modification has been successfully used in the production of aluminum casting, and it also meets the high requirements of environmental protection in the industry.However, there are still many problems in the production of cast iron, such as low strength at indoor temperature, especially in high humidity environment, and high residual strength at high temperature, so it is necessary to carry out further research. Therefore, after preliminary screening tests, a new inorganic binder was selected to investigate the influence of various factors on the strength of core sand samples. The results showed that in a certain range, the higher the amount of binder and hardening agent, the higher the normal temperature strength and high temperature residual strength of the core sand. With the increase of mold temperature, the strength of the core sand at room temperature increased first and then decreased, while the residual strength was less affected by the mold temperature. Raw sand had the greatest influence on the strength properties of the core sand. The good fluidity and physical and chemical properties of spherical ceramic sand improved the strength at room temperature, but were not conducive to the reduction of residual strength, while the residual strength of silica sand was lower. The optimized process by orthogonal test was as follows: using 50/100 silica sand, adding 2.4% binder, hardening agent 50% binder, mold temperature 180 ℃, the strength of the core sand at room temperature of 24 h was 2.71 MPa, the strength of the core sand at 98% RH was 2.39 MPa, the residual strength of the core sand at 800 ℃ was 0.13 MPa.更多还原