In an effort to explore the use of natural resources, stoneware ceramics have been made using iron sand as a filler to replace quartz Kalimantan. The results showed that iron sand can be well used in making stoneware ...In an effort to explore the use of natural resources, stoneware ceramics have been made using iron sand as a filler to replace quartz Kalimantan. The results showed that iron sand can be well used in making stoneware ceramics. This is shown by the measurement of water absorption which is less than 5% and has compressive strength slightly smaller compared to stoneware ceramics made with quartz as a filler.展开更多
The effects of metallurgical and processing parameters on the formation of shrinkage cavities and porosities in spheroidal graphite cast iron have been studied, considering the parameters of carbon equivalent, inocula...The effects of metallurgical and processing parameters on the formation of shrinkage cavities and porosities in spheroidal graphite cast iron have been studied, considering the parameters of carbon equivalent, inoculation, casting modulus, mold type (green or dry) and pouring temperature within specific ranges of these variables. Based on the orthogonal experiments, the metallurgical and processing parameters of the minimum casting shrinkage and the maximum casting shrinkage were obtained, and the effects of metallurgical and processing parameters on the formation of shrinkage cavities and porosities in spheroids graphite cast iron castings were discussed. Finally, two regression equations relating these variables to the formation of shrinkage porosity were derived based upon the orthogonal experiments conducted.展开更多
铁尾矿机制砂被广泛应用于混凝土中,然而部分铁尾矿机制砂中硫含量过高,可能会造成混凝土膨胀开裂。本文配制了不同硫含量的铁尾矿机制砂混凝土,研究硫含量对混凝土工作性能、力学性能和耐久性能的影响规律,并采用X R D、压汞、SEM等微...铁尾矿机制砂被广泛应用于混凝土中,然而部分铁尾矿机制砂中硫含量过高,可能会造成混凝土膨胀开裂。本文配制了不同硫含量的铁尾矿机制砂混凝土,研究硫含量对混凝土工作性能、力学性能和耐久性能的影响规律,并采用X R D、压汞、SEM等微观测试分析了铁尾矿机制砂中硫含量对混凝土性能的影响机理。结果表明:铁尾矿机制砂中硫含量的增加显著影响混凝土的工作性能;硫含量为2%的C30铁尾矿机制砂混凝土早期强度最高,养护龄期在3 d和7 d时,混凝土抗压强度比空白组分别提升了14.4%、11.7%,其抗碳化性能和抗氯离子扩散能力均优于其他硫含量的混凝土。少量的硫化物可以提供充足的SO42-,激发水泥混合材水化反应的进行;含硫量过高则会导致混凝土中的A Ft和石膏等膨胀性晶体增加,混凝土内部产生较大应力,造成混凝土开裂,对后期强度发展不利,对于铁尾矿机制砂混凝土,硫含量不宜超过4%。展开更多
文摘In an effort to explore the use of natural resources, stoneware ceramics have been made using iron sand as a filler to replace quartz Kalimantan. The results showed that iron sand can be well used in making stoneware ceramics. This is shown by the measurement of water absorption which is less than 5% and has compressive strength slightly smaller compared to stoneware ceramics made with quartz as a filler.
基金The paper was financially supported by the National Natural Science Foundation of China(Grant No.59235102).
文摘The effects of metallurgical and processing parameters on the formation of shrinkage cavities and porosities in spheroidal graphite cast iron have been studied, considering the parameters of carbon equivalent, inoculation, casting modulus, mold type (green or dry) and pouring temperature within specific ranges of these variables. Based on the orthogonal experiments, the metallurgical and processing parameters of the minimum casting shrinkage and the maximum casting shrinkage were obtained, and the effects of metallurgical and processing parameters on the formation of shrinkage cavities and porosities in spheroids graphite cast iron castings were discussed. Finally, two regression equations relating these variables to the formation of shrinkage porosity were derived based upon the orthogonal experiments conducted.
