Ductile iron, a material that is often used because of its wide application. Moreover, only after a correct understanding of this material can be used to achieve the correct and rational use of the product and achieve the purpose of use, rather than wrong or improper use, thereby causing waste of materials.
1. How to ensure the good performance of ductile iron?
In order to ensure the good performance of ductile iron, it is necessary to pay attention to some aspects, which are specifically as follows:
Pour the riser: If the pouring system and the riser are not properly set, not only can the molten metal be solidified in sequence, but also the feeding effect of the riser. In addition, the number and size of the riser and the connection with the casting are appropriate. Affects the feeding effect that affects the riser.
Phosphorus: If the content of phosphorus in the molten iron is too high, the solidification range will be enlarged, but the outer shell of the casting will be brittle, and defects such as shrinkage and shrinkage may occur. Therefore, in the content of phosphorus, it is generally controlled within 0.08%.
Rare Earth and Magnesium: If the content of rare earth is too high, the spheroidization rate of ductile iron will be reduced. Magnesium will hinder the graphitization of materials. Therefore, their content should not be too high and should be controlled within a reasonable range.
Wall thickness: The wall thickness should not change too suddenly, because it may cause defects such as shrinkage and shrinkage.
Temperature: The pouring temperature should be reasonably selected and determined. The temperature is too high or too low. Generally speaking, the suitable temperature is 1300 °C - 1350 °C.
Avoidance of subcutaneous stomata: This is also an aspect that needs attention, because if there are subcutaneous stomata, it will affect the quality of the product and the performance of the product, so this specific requirement will be met.
2. Comparison of ductile iron manhole cover and gray cast iron manhole cover in cast iron manhole cover
In the cast iron manhole cover, there are two types of manhole covers, a ductile iron manhole cover and a gray cast iron manhole cover. If they are compared, it can be concluded that the ductile iron manhole cover has stronger compressive capacity than the gray cast iron manhole cover under the same weight. . Moreover, they are different in material, the gray cast iron manhole cover material is HT200, and the ductile iron manhole cover material is QT500-7.
3. Comparison of mechanical properties of ductile iron, gray iron and compacted graphite iron and some notes on ductile iron
The mechanical properties of spheroidal graphite cast iron, gray iron and compacted graphite cast iron are compared. The mechanical properties of ductile iron are higher than that of gray iron and vermicular graphite iron, followed by vermicular graphite iron, followed by gray iron.
Some notes on ductile iron are: Q235B, which is not ductile iron, because ductile iron has a higher carbon content than Q235B. In addition, the different grades of ductile iron are corresponding to different hardness, toughness and test temperature, so it should be noted at this point that it should not be sloppy.www.xihuafoundry.com