The casting coating is composed of five basic components: refractory aggregate, carrier, binder, suspending agent and additives. With the development of technology, the casting coating has expanded from single sand prevention to multiple functions such as anti veining, sintering, porosity, leakage and sand hole, so as to meet the...
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...
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...
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....
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...
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...
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) ....
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...
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,...
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,...