What is chromite sand used for?
46% Chromite sand is composed of chromium, iron, and oxygen (chemical formula FeCr2O4). It is an oxide mineral belonging to the spinel group. 46% content referring to Cr2O3 content more than 46%. The 46% chromite is mainly from the western ore belt centered around Rustenburg in South Africa and the eastern ore belt centered around STEELPORT and BUGERSFORT. Chromium ore sand has the characteristics of high sintering temperature, high thermal conductivity, and high specific gravity.
The 46-content chrome ore sand obtained from the separation of chromite raw ore after mining will be broken into different particle sizes according to needs. Commonly used ones include 0-5mm, 1-2mm, 2-5mm, 20-30 mesh (0.6-0.85mm), 20-40 mesh (0.425-0.85mm), 20-50 mesh (0.3-0.85mm), 20-60 mesh (0.25-0.85mm), 20-70 mesh (0.85-0.212mm), 40-70 mesh (0.2-0.4mm), 50-100 mesh (0.15-0.3mm), 70-140 mesh (0.1-0.2mm), 200-0325 mesh -0400 mesh -0, etc. Different uses have different requirements for particle size, among which chromite sand used for metallurgy and casting is classified according to AFS fineness.
Overall, the uses of chromite sand are mainly divided into several categories:
1. Casting.
- Coarse chromite sand AFS20-25, AFS25-30, etc. are used in casting processes such as lost foam casting and wet mold casting.
- Moderately fine chromite sand AFS35-40, AFS40-45, AFS45-50, AFS45-55, AFS50-55, etc. are used for no-bake sand processes such as furan resin, alkali phenolic resin, water glass, and Pep-set resin. Mainly used for facing sand, core sand, and molding sand in metal and iron and steel casting.
- Fine-grade chromite sand AFS60-65, AFS55-65, AFS65-70, etc. are used for sand cores and other parts in investment casting.
- The 325 # chrome ore powder ground from chromite sand can be used for casting coatings.
At the same time, chrome ore sand with different fineness is also selected for casting based on the size of the casting.
2. Metallurgy.
Chromium iron is used for smelting chromium-containing alloys. However, the 46% chromite sand is mainly used in metallurgy to make ladle drainage sand. Chromium filler sand can improve the pouring rate.
3. Wear-resistant materials.
Adding fine powders such as chromite sand 70-140 #, 200 #, and 325 # to brake pads or wear-resistant products can improve the anti-wear performance of the product.
4. Refractory materials.
Chromite sand and chromite powder are used in the production of refractory castables, as well as in the production of chrome refractory bricks and castables.
5. The glass and ceramic industry.
After grinding chromite sand into flour of 45 microns or 38 microns, it can be used as a green/brown colorant for float glass containers and as a brown/green glaze for ceramic products. Replacing chromium oxide green with chromite flour can reduce the production cost of glass containers.
