Production and properties of thin-wall ductile iron castings
Production and properties of thin-wall ductile iron castings
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薄壁球墨铸铁件的生产及性能
DOI：
10.1080/13640461.2003.11819601
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发表时间：
2003
期刊：
影响因子：
--
通讯作者：
M. Sahoo
中科院分区：
文献类型：
--
作者：
C. Labrecque;M. Gagné;A. Javaid;M. Sahoo
汽车和卡车对燃油效率的要求导致汽车工业中铝等低密度材料的使用增加。然而，这种材料的生产需要大量的能源，在强度和成本方面也有明显的缺点。因此，它们并不是减肥的灵丹妙药。由于球墨铸铁的可铸造性、强度重量比和成本，它仍然是汽车应用的首选材料。事实上，假设在铸态条件下这些零件可以不含碳化物生产，那么球墨铸铁的机械性能允许减小铸件尺寸。为设计无共晶碳化物薄壁球墨铸铁件的生产路线进行了全面的研究。在本研究中，使用计算机建模技术设计了一个具有实际铸件代表的截面厚度从3到10毫米的试铸组件。用不同的工艺参数生产了各种化学成分的铸件。研究表明，使用含铋硅铁等强力孕育剂，可以制备出无碳化物的3mm厚铸件。在这种情况下，可以生产出超过1200个结核数的无碳化物铸件，同时硅含量保持在合理水平（< 2.8%）。在此条件下，控制结核数量和基体结构的不是硅含量，而是冷却速率和孕育率。试验铸件的机械性能略低于传统的截面铸件，但在许多应用中足以与轻金属竞争。研究了进一步改善力学性能的途径，包括发现过滤可以提高力学性能的一致性。
Fuel efficiency requirement for cars and trucks has conducted to an increased use of low-density materials such as aluminium in the automotive industry. However, such materials, which require tremendous amounts of energy for their production, have also significant drawbacks with respect to strength and cost. Therefore, they do not represent the panacea for weight reduction. Ductile iron remains a material of choice for automotive applications due to its castability, strength-to-weight ratio and cost. Indeed, the mechanical properties of Ductile Iron allow the reduction of the casting size, assuming that such parts could be produced carbide free in the as-cast condition. A comprehensive study was carried out to design a production route for thin wall Ductile Iron castings free of eutectic carbides. In this study, a test casting assembly with section thicknesses from 3 to 10 mm representative of actual castings was designed using computer modeling technique. Castings of various chemical compositions produced using different processing parameters were manufactured. The study showed that carbide free 3 mm thick castings can be manufactured when powerful inoculants, such as Bi-bearing ferro-silicon, are used. In such cases, carbide free castings with nodule count in excess of 1200 can be produced, while maintaining silicon content at a reasonable level (< 2.8%). Under these conditions, cooling rate and inoculation rather than silicon content control nodule count and matrix structure. The mechanical properties of the test castings were found slightly inferior to those of conventional section castings, but sufficiently high to compete with light metals in many applications. Routes to further improve the mechanical properties were investigated, including filtering which was found to improve the consistency of the mechanical properties.