The strength of gray cast iron is mainly determined by graphite shape, size, pearlite in matrix and ferrite proportion. With the increase of exhaust temperature of the engine, the grey cast iron with high carbon equivalent can not meet the requirements of application because the oxide film will form...
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The method of obtaining A-type graphite from high strength gray cast iron
The traditional method of high strength gray iron is to reduce the eutectic degree, to increase the austenite content and the branching of austenite dendrite, and to reduce the amount of graphite. However, the increase in strength is at the expense of casting properties. The low eutectic degree reduces...

Comparison of corrosion resistance between nodular cast iron and gray cast iron
The mass fraction of carbon in iron is higher than 2%, while that of silicon is between 1% and 3%. Cast iron is widely used in industry because of its low cost, easy pouring, low notch sensitivity, good wear resistance and shock absorption, and corrosion resistance to some media....

The important role of adjusting sand mold temperature in large gray iron casting
In order to adjust the sand temperature, the air temperature must be considered. Although the curing reaction of resin sand is exothermic, the air temperature directly affects the sand temperature. If the temperature is below 10 ℃ or above 30 ℃, it may have a negative effect on the...

Application of furan resin in large gray iron castings
Furan resin can be divided into urea formaldehyde furan resin, phenol urea formaldehyde furan resin, formaldehyde sugar alcohol resin and high sugar alcohol resin. The price of UF resin is low, because of its high nitrogen content (5% – 11%). Although the strength of resin sand is high, the...

Size and position selection of cold iron for large gray iron castings
For the role of cold iron in the anti shrinkage process of castings, the sequential solidification theory and the equilibrium solidification theory are both attached great importance (1) . place it at the place where it is difficult to make up the shrinkage to prevent shrinkage defects; (2) ....

Design principle of riser for large gray iron castings
In the past, riser design basically followed the principle of sequential solidification, which needs to meet the following three conditions: (1) . the solidification time of molten iron in the riser shall not be less than the solidification time of the feeding position. (2) There is enough iron water...

Selection of riser size and location for large gray iron castings
The use of riser is one of the basic means to solve the shrinkage of casting. Although there are new views and new views on riser setting in recent years, the key role played by the team of zhycasting senior engineers has never been questioned. In the actual production,...

The influence of metallurgical and modeling factors on shrinkage porosity
At present, there are many researches on the influence of metallurgical and molding factors on shrinkage cavity and porosity of gray iron castings. The following factors are discussed: 1) Composition and temperature of molten iron For gray cast iron, the elements related to shrinkage porosity include carbon, sulfur, flow,...

How to Correctly Select a Reasonable Casting Temperature during Manufacture of Gray Iron Foundry
I. Too High Casting Temperature will Greatly Increase its Rejection Rate. Too high casting temperature will make sand moulds inflate, especially for theses gray iron foundry with complicated sand cores. When the casting temperature reaches ≥1420℃, corresponding rejection rate will begin to increase. And when the temperature is up...
