硬质合金类烟机配件的性能改善

硬质合金由于其很高的硬度和光洁度而具有很好的耐磨性,但硬度越高,其脆性就大,不利于零件后期的加工。我们通过在硬质合金混合料中添加稀土氧化物Y2O3、CeO2、La2O3,可提高其加工性并改善硬质合金的耐磨性。     

斜轧低铬白口铁磨球的抗多冲击破坏能力与耐磨性

通过落球和冲击磨损试验,测试了斜轧低铬白口铁磨球的抗小能量多冲击破坏能力和耐磨性,并对其破坏形式和磨损面特征进行了分析。结果表明,该球经适当的余热热处理可获得较高的抗多冲击破坏能力与耐磨性能。     

Effect of geomechanical properties on Cerchar Abrasivity Index (CAI) and its application to TBM tunnelling

Abrasiveness of rocks plays an important role in the wear of TBM tunnelling. Cerchar Abrasivity Index (CAI) test is the most commonly used method to estimate rock abrasiveness due to its simple, fast test procedure and economic benefits. This study investigated the correlation between CAI and geomechanical properties of igneous and metamorphic rocks. Single and multiple regression analysis were performed and predictive models for the CAI from geomechanical properties were developed. It is found that single parameter alone is not suitable to predict the value of CAI. The result of the multiple regression analysis shows that quartz content is less influencing factor to predict the value of CAI. Also, the correlation between CAI and NTNU’s Cutter Life Index (CLI) was examined and a predictive model for the CLI from CAI and geomechanical properties was suggested. Finally, the influence of CAI on disc cutter life prediction models was investigated and it was found that the variation of CAI has the maximum effect on the predicted disc cutter life in Gehring model.     

无烟煤在配煤炼焦中的性质研究

通过对无烟煤的热稳定性、可磨性的研究,选择适用于配煤炼焦的无烟煤,并在5kg试验焦炉进行了配煤炼焦试验。同时还比较了涟钢生产配煤方案与配无烟煤方案的焦炭冷强度,结果表明:当无烟煤配入量为3%～5%、无烟煤粒度≤1mm时,焦炭冷强度约提高2%。这对扩大炼焦煤源,降低生产成本具有现实与长远意义。     

纳米稀土La2O3对Ni基合金喷焊层组织和耐磨性的影响

采用氧-乙炔火焰喷焊技术在Q235钢基体表面喷焊含不同量纳米稀土La2O3的Ni基自熔性合金粉末,对获得的喷焊层进行了组织、结构分析和硬度、耐磨性测定。研究了不同时效温度对喷焊层硬度和耐磨性的影响。试验结果表明,与不含稀土La2O3的喷焊层相比,加入适量的稀土La2O3,可细化喷焊层的显微组织,提高喷焊层的硬度和耐磨性;在一定温度下对喷焊层进行时效处理,可进一步提高其硬度和耐磨性。