Application of ceramic sand on wear-resistant castings

Characteristics of spherical ceramic sand for casting
[Characteristics]
1, because of the solid appearance of the gravel and the small surface area, the amount of 1/3 binder (resin, R2O nSiO2 and so on) can be reduced. Good fluidity, making sand mold, core easy to fill the dense no dead angle, in the casting process, low gas and good air permeability, can reduce defects to improve the rate of finished products and reduce the cost of raw materials.
2. High refractoriness, low thermal expansion coefficient and good high temperature stability. During the casting process, no sand sticking, no sintering and easy collapsing can greatly reduce the deformation of castings, reduce cleaning work and reduce labor intensity.
3, the particle size distribution is reasonable, and the strength of mold and core is improved.
4, the bulk density of JNY-XT (casting spherical ceramic sand) is 1.79-1.87g/cm less than the accumulation density of chromium iron ore (2.5~2.7g/cm), and the weight of the sand core is easily carried and the use of core sand is reduced.
5. The non natural mineral sand belongs to the high temperature smelting artificial sand making, the chemical index is stable, the physical property is unified, the PH is neutral, and it can be constructed with all kinds of acid and alkaline binder.
6. High temperature is not cracked, the hardness of the spherical gravel is high, and the recycling rate is high.
Application scope of JNY-TCS (spherical ceramic sand for casting)
1, widely used in resin sand, sodium silicate sand, clay sand casting process sand core and type sand.
2. The substitute chromite ore is widely used in sand core sand for sand core of engine water jacket core, oil channel core and tappet core.
3. Replace the chromite ore as the surface sand and the secondary sand (back sand) for the steel castings.
4, commonly used as sand mold dry sand used in EPC process and V process.
5. As the main raw materials for advanced refractory products (ladle draining sand, self flow castable, casting coating etc.).
6. It is widely used as cleaning sand for casting copper and aluminum alloy castings.
Application of spherical ceramic sand for casting in the production of wear resistant castings
The spherical ceramic sand used for casting is a synthetic spherical refractory particle of aluminum silicon system formed by the high temperature melting of the EAF and the high temperature smelting by electric arc furnace. TCS has an artificial property with uniform chemical composition and stable physical properties. It is different from the existing spherical sand (pearl sand, electric melting ceramsite, etc.) in the market.
1, linear expansion rate
The expansion of TCS is linear expansion without phase transformation and sintering.
2, grain shape
3. Refractoriness
According to the index listed in Table 1, TCS is in accordance with the data shown in the two element phase diagram of Al Si refractory material, and the refractoriness is >1850 C through the inspection by the third party inspection mechanism.
4. Advantage of using sodium silicate as binder to produce high manganese steel.
(1) promoting grain refinement
Principle: it is well known that, in order to improve the wear resistance of high manganese steel castings, its grain must be refined, the primary condition for grain refinement is to make it fast and uniformly cool, then how to let the high temperature cast metal liquid can lose the heat evenly and quickly is the weight of the weight.
1 thermal conductivity
TCS is a high density solid spherical sand produced by manual smelting. The thermal conductivity is greater than that of silica sand, which is slightly smaller than that of chromite ore. It is between 0.3-0.5W/ (MK).
2 permeability
In the casting model, heat loss is carried out by air flow at high temperatures. Under the accumulation state, the TCS is uniform and orderly with the capillary network structure which can directly connect the air. Under the physical action of the hot air, the heat is evenly and quickly carried away through the capillary network to complete the rapid and uniform cooling. The thermal conductivity is smaller than that of chromite. Beyond the defects of chromite sand, though the thermal conductivity is strong, the accumulated heat can not be taken away quickly.
The above two points indicate that TCS has excellent heat dissipation ability and can promote crystal refinement.
(2) melt recycled materials for neutral materials
The melting material of neutral material contains the following meaning: resist the erosion of grit by manganese alloy under high temperature, remove impurity after high temperature, and have uniform physical and chemical properties.
3, reduce the amount of binder added
Through the application test, the water glass carbon dioxide hardening process is used in the TCS modeling, and the same construction strength is achieved. The addition of water glass is 2-3%, which is less than the 6-7% of silicon sand.
The decrease of the amount of water glass can reduce the content of water in the molding sand in order to reduce the gas defects, improve the collapsibility of the sand, reduce the labor intensity and production cost, and reduce the discharge of the waste.
4. High recovery and reuse performance
TCS gravel has high surface density, high temperature, no cracking, no breakage, little grain shape change and low regeneration cost.