High temperature casting
2020年6月13日https://www.bronzecast.net/
In short, the refractory filler is the main part of the paint, which plays a decisive role in the effect of the paint. Xiangyu uses a 5000 high-magnetic double-roller magnetic separator to perform magnetic separation twice, and the magnetic objects are selected up to about 25%. 2. (3) Magnesia powder is easy to absorb water and damp, and special attention should be paid to the water content in the powder. When used, it should be graded according to the particle size of the refractory filler for coatings. 6. well.2 The particle size and particle size distribution of the particle size bauxite are important factors affecting the density and permeability of the coating, especially the lost foam paint, the pyrolysis products of the foam plastic pattern during the sintering process can be smoothly discharged through the coating, the lost foam The breath ability of the paint is a major feature different from other sand casting paints. In addition, there are waste sand wheels on the market to make corundum powder, which has high impurity content, so special attention should be paid when purchasing. 4. White corundum is made of alumina powder through electric melting and recrystallization, and its basic minerals It is a-Al2O3, the former is greater than 94%, the latter is greater than 97%, corundum has high hardness, high melting point, large thermal conductivity, good thermal stability, not easy to crack, good acid resistance and alkalinity, brown corundum powder is suitable for preparation For common cast steel and alloy steel coatings, white corundum powder is often used as a composite filler for large cast steel coatings due to its high price.
The impurity content is relatively high. The particles are dense and hard, and the MgO content is greater than 90% Otherwise, the coating is prone to cracking during high temperature casting. Coatings and small pieces of cast steel coating can be compounded with fused quartz powder and ordinary quartz powder, which is used in lost foam casting steel and cast iron coatings, effectively sending out cracks and flaking of the paint due to the phase expansion of quartz powder. The selection of refractory fillers should focus on the main indicators of refractory fillers such as mineral composition, purity, impurity content, and particle size composition. The smaller the content of serpentine (aqueous magnesium silicate), the better, generally not more than 20%, otherwise the refractoriness will decrease, and the ignition loss and gas generation will increase. The characteristics of fused silica powder are: low thermal expansion rate, good thermal stability, and high temperature creep resistance, especially suitable for lost foam coatings. Many coating manufacturers are looking for alternative products of zircon powder to reduce the cost of cast steel coatings. 1 The chemical composition Al2O3 content in bauxite, sintering temperature and Ti02, FeO3 and other impurities have a great influence on the coating, so the ore with high Al2O3 content is selected and calcined at 1450℃-1500℃, then selected clinker is ground and prepared After the fine powder is formed, the pickling treatment is still a key step., depending on the bronze cast factory paint It can be used alone or as a refractory filler after compounding. In recent years, the source of zirconium powder has been more complicated and the price has been rising. Imported zircon powder is mostly used in foreign countries. A good refractory filler, mostly used for stainless steel and high alloy steel castings. It also has an important influence on the air permeability and sinter peelability of the coating. The content of iron oxide in the forsterite powder should be mainly controlled, not more than 10%.
The reaction of the material is conducive to the anti-sticking property of the paint, and the price is only one-third of the zircon powder. The mechanical iron mixed in is difficult to remove by magnetic separation. 1. (2) The sintered block contains iron and iron oxide components and other magnetic objects are quite high. (Currently, bauxite The processing of the fine powder is mainly Raymond mill, and the wear-resistant parts are mostly high-strength steel castings. 1. According to different needs, Xiangyu Company grades the particle size of bauxite into two different specifications for use in sand casting paint and lost foam paint. In the lost foam casting, how to choose the refractory filler of the coating mainly considers the following properties of the filler: (1) refractoriness; (2) density; (3) thermal expansion coefficient; (4) particle type and particle size distribution; (5) and The chemical reactivity of the metal liquid; (6) the amount of gas generated; (7) the mutual compatibility with other components in the coating; (8) whether it affects the health and environment of the workers. The refractoriness, linear expansion coefficient, and chemical stability are close to zirconium powder, and it does not oxidize with FeO3 and other alkaline. Big. Therefore, in order to obtain high-quality magnesia powder, magnetic separation is a key step. 3. The particle size distribution of bauxite used in lost foam coating is: -270 mesh to -320 Mesh 78% -200 mesh to -270 mesh 15% -100 mesh to -200 mesh 5% +100 mesh not more than 2% The particle size distribution is also suitable for the gradation of other refractory fillers. Xiangyu successfully developed an artificial Synthetic new refractory filler N-3 powder has been widely used in cast steel coatings. As we all know, casting paint is composed of five basic components of carrier, refractory filler, suspending agent, binder and auxiliary additives, of which refractory filler is the main component, which determines the fire resistance, chemical stability and heat insulation of the paint.. Bauxite powder Bauxite is widely used in ordinary cast steel coatings and cast iron coatings in recent years due to its high refractoriness, good chemical stability, small expansion coefficient, abundant sources, and low prices. The main component of magnesium sea powder is the sintered block obtained by calcining natural magnesite ore (MgCO2) It is processed by crushing, grinding and magnetic separation. In addition to the high content of Ti02 and FeO3, the bauxite without pickling treatment has increased dust and mechanical iron mixed during the calcination and grinding process. It should be noted that the particle size distribution and label of the corundum powder for abrasives and the corundum powder for foundry coatings are inconsistent. The Zr02 content is greater than 65% and the content of impurities is low. Quartz powder and fused quartz powder Quartz powder is one of the traditionally used refractory fillers. Brown corundum powder and white corundum powder Brown corundum is made of bauxite as raw material, and is processed at a high temperature of 2000°C-2400°C.) The prepared coating is affected by the refractoriness first, and the floating matter and precipitates Increase, affect the paintability, suspension and storage time of the paint. Due to its low price and abundant resources, it is still used by many manufacturers, but its low refractoriness and large linear expansion coefficient are only suitable for casting.
It is not elaborated here one by one, all are provided by Xiangyu Company. Therefore, it can be said that the quality of the refractory filler is the key factor for the quality of the cast coating. Most of the zircon powder processed in China is Raymond mill. Magnesia powder and forsterite powder Magnesia powder and forsterite powder are usually used as the first choice refractory materials for the preparation of coatings for alkaline steel castings. The particle size distribution of bauxite powder used in sand casting coating is: -270 mesh to 320 mesh, the concentration rate is 96% +270 mesh is not more than 1%. 5. Zircon powder and N-3 powder are made of zircon sand, which has a small linear expansion coefficient, good thermal shock stability, high refractoriness and does not chemically affect most alloys at high temperatures. Other refractory fillers In addition to the refractory fillers mentioned above, there are mullite powder, chromite powder, high aluminum steel jade powder, diatomaceous earth powder, talc powder, mica powder, feldspar powder, etc. N-3 powder is synthesized from several natural refractory materials in proportion, fused, crushed, and washed with acid. The following points deserve special attention: (1) The sintered block must be a so-called burn-out block calcined at 1500℃-1600℃.Casting paint affects the internal and surface quality of castings, especially lost foam paint is one of the key factors to control and ensure the quality of lost foam casting
In short, the refractory filler is the main part of the paint, which plays a decisive role in the effect of the paint. Xiangyu uses a 5000 high-magnetic double-roller magnetic separator to perform magnetic separation twice, and the magnetic objects are selected up to about 25%. 2. (3) Magnesia powder is easy to absorb water and damp, and special attention should be paid to the water content in the powder. When used, it should be graded according to the particle size of the refractory filler for coatings. 6. well.2 The particle size and particle size distribution of the particle size bauxite are important factors affecting the density and permeability of the coating, especially the lost foam paint, the pyrolysis products of the foam plastic pattern during the sintering process can be smoothly discharged through the coating, the lost foam The breath ability of the paint is a major feature different from other sand casting paints. In addition, there are waste sand wheels on the market to make corundum powder, which has high impurity content, so special attention should be paid when purchasing. 4. White corundum is made of alumina powder through electric melting and recrystallization, and its basic minerals It is a-Al2O3, the former is greater than 94%, the latter is greater than 97%, corundum has high hardness, high melting point, large thermal conductivity, good thermal stability, not easy to crack, good acid resistance and alkalinity, brown corundum powder is suitable for preparation For common cast steel and alloy steel coatings, white corundum powder is often used as a composite filler for large cast steel coatings due to its high price.
The impurity content is relatively high. The particles are dense and hard, and the MgO content is greater than 90% Otherwise, the coating is prone to cracking during high temperature casting. Coatings and small pieces of cast steel coating can be compounded with fused quartz powder and ordinary quartz powder, which is used in lost foam casting steel and cast iron coatings, effectively sending out cracks and flaking of the paint due to the phase expansion of quartz powder. The selection of refractory fillers should focus on the main indicators of refractory fillers such as mineral composition, purity, impurity content, and particle size composition. The smaller the content of serpentine (aqueous magnesium silicate), the better, generally not more than 20%, otherwise the refractoriness will decrease, and the ignition loss and gas generation will increase. The characteristics of fused silica powder are: low thermal expansion rate, good thermal stability, and high temperature creep resistance, especially suitable for lost foam coatings. Many coating manufacturers are looking for alternative products of zircon powder to reduce the cost of cast steel coatings. 1 The chemical composition Al2O3 content in bauxite, sintering temperature and Ti02, FeO3 and other impurities have a great influence on the coating, so the ore with high Al2O3 content is selected and calcined at 1450℃-1500℃, then selected clinker is ground and prepared After the fine powder is formed, the pickling treatment is still a key step., depending on the bronze cast factory paint It can be used alone or as a refractory filler after compounding. In recent years, the source of zirconium powder has been more complicated and the price has been rising. Imported zircon powder is mostly used in foreign countries. A good refractory filler, mostly used for stainless steel and high alloy steel castings. It also has an important influence on the air permeability and sinter peelability of the coating. The content of iron oxide in the forsterite powder should be mainly controlled, not more than 10%.
The reaction of the material is conducive to the anti-sticking property of the paint, and the price is only one-third of the zircon powder. The mechanical iron mixed in is difficult to remove by magnetic separation. 1. (2) The sintered block contains iron and iron oxide components and other magnetic objects are quite high. (Currently, bauxite The processing of the fine powder is mainly Raymond mill, and the wear-resistant parts are mostly high-strength steel castings. 1. According to different needs, Xiangyu Company grades the particle size of bauxite into two different specifications for use in sand casting paint and lost foam paint. In the lost foam casting, how to choose the refractory filler of the coating mainly considers the following properties of the filler: (1) refractoriness; (2) density; (3) thermal expansion coefficient; (4) particle type and particle size distribution; (5) and The chemical reactivity of the metal liquid; (6) the amount of gas generated; (7) the mutual compatibility with other components in the coating; (8) whether it affects the health and environment of the workers. The refractoriness, linear expansion coefficient, and chemical stability are close to zirconium powder, and it does not oxidize with FeO3 and other alkaline. Big. Therefore, in order to obtain high-quality magnesia powder, magnetic separation is a key step. 3. The particle size distribution of bauxite used in lost foam coating is: -270 mesh to -320 Mesh 78% -200 mesh to -270 mesh 15% -100 mesh to -200 mesh 5% +100 mesh not more than 2% The particle size distribution is also suitable for the gradation of other refractory fillers. Xiangyu successfully developed an artificial Synthetic new refractory filler N-3 powder has been widely used in cast steel coatings. As we all know, casting paint is composed of five basic components of carrier, refractory filler, suspending agent, binder and auxiliary additives, of which refractory filler is the main component, which determines the fire resistance, chemical stability and heat insulation of the paint.. Bauxite powder Bauxite is widely used in ordinary cast steel coatings and cast iron coatings in recent years due to its high refractoriness, good chemical stability, small expansion coefficient, abundant sources, and low prices. The main component of magnesium sea powder is the sintered block obtained by calcining natural magnesite ore (MgCO2) It is processed by crushing, grinding and magnetic separation. In addition to the high content of Ti02 and FeO3, the bauxite without pickling treatment has increased dust and mechanical iron mixed during the calcination and grinding process. It should be noted that the particle size distribution and label of the corundum powder for abrasives and the corundum powder for foundry coatings are inconsistent. The Zr02 content is greater than 65% and the content of impurities is low. Quartz powder and fused quartz powder Quartz powder is one of the traditionally used refractory fillers. Brown corundum powder and white corundum powder Brown corundum is made of bauxite as raw material, and is processed at a high temperature of 2000°C-2400°C.) The prepared coating is affected by the refractoriness first, and the floating matter and precipitates Increase, affect the paintability, suspension and storage time of the paint. Due to its low price and abundant resources, it is still used by many manufacturers, but its low refractoriness and large linear expansion coefficient are only suitable for casting.
It is not elaborated here one by one, all are provided by Xiangyu Company. Therefore, it can be said that the quality of the refractory filler is the key factor for the quality of the cast coating. Most of the zircon powder processed in China is Raymond mill. Magnesia powder and forsterite powder Magnesia powder and forsterite powder are usually used as the first choice refractory materials for the preparation of coatings for alkaline steel castings. The particle size distribution of bauxite powder used in sand casting coating is: -270 mesh to 320 mesh, the concentration rate is 96% +270 mesh is not more than 1%. 5. Zircon powder and N-3 powder are made of zircon sand, which has a small linear expansion coefficient, good thermal shock stability, high refractoriness and does not chemically affect most alloys at high temperatures. Other refractory fillers In addition to the refractory fillers mentioned above, there are mullite powder, chromite powder, high aluminum steel jade powder, diatomaceous earth powder, talc powder, mica powder, feldspar powder, etc. N-3 powder is synthesized from several natural refractory materials in proportion, fused, crushed, and washed with acid. The following points deserve special attention: (1) The sintered block must be a so-called burn-out block calcined at 1500℃-1600℃.Casting paint affects the internal and surface quality of castings, especially lost foam paint is one of the key factors to control and ensure the quality of lost foam casting
