Calcium, denoted by the chemical symbol Ca and atomic number 20, is classified as an alkaline earth metal. Due to its high chemical activity, a black film composed of nitride and oxide forms on its surface when exposed to air. This characteristic makes it highly reactive in various industrial processes, particularly in metallurgical applications where its reducing properties are invaluable.
Metallic calcium appears as a silver-white metal and serves multiple critical roles in industrial production. It is primarily utilized as a deoxidizer, decarburizer, and desulfurizer in the manufacturing of alloy steel and special steel. Additionally, it functions as an effective reducing agent in the production processes of high-purity rare earth metals, contributing to the purification and quality enhancement of these materials.
Product Specifications of Calcium Metal (Ca98.5%)
The following table details the chemical composition and impurity limits of our high-quality calcium metal (Ca98.5%), ensuring compliance with industrial standards and customer requirements:
| Element | Content |
| Calcium (Ca) | Minimum 98.5% |
| Chlorine (Cl) | Maximum 0.2% |
| Nitrogen (N) | Maximum 0.1% |
| Magnesium (Mg) | Maximum 0.8% |
| Copper (Cu) | Maximum 0.02% |
| Nickel (Ni) | Maximum 0.005% |
| Manganese (Mn) | Maximum 0.03% |
| Silicon (Si) | Maximum 0.01% |
| Iron (Fe) | Maximum 0.01% |
| Aluminum (Al) | Maximum 0.5% |
Product Details & Supply Capacity
As a leading manufacturer and supplier of ferroalloy materials, ZX Ferroalloy specializes in providing calcium metal with a purity of 98.5%. Our product is available in various forms, including lump, granule, particle, and powder, to meet diverse application scenarios. With a monthly supply capacity of up to 3,000 metric tons, we can fulfill large-volume orders efficiently and on time.
The following table summarizes the key product information for our calcium metal (Ca98.5%):
| Item | Details |
| Product Name | Calcium Metal (Ca98.5%) |
| Chemical Formula | Ca |
| Shape | Lump, Granule, Powder, Wire |
| Color | Silver-gray |
| Grade | Ca98.5% |
| Size | 10-50mm, 10-100mm, 0-2mm, 0.1-1mm (customizable) |
| Application | Casting, Steelmaking, Metallurgy, Chemical Industry |
| Certification | SGS, CIQ |
| Minimum Order Quantity (MOQ) | 25 Tons |
| Packaging | 1MT/bag; 125kg-250kg steel drums; Custom packaging available upon negotiation |
| Place of Origin | China |
Physical & Chemical Properties of Metallic Calcium
Metallic calcium possesses distinct physical and chemical properties that make it suitable for a wide range of industrial uses. It has a relative density of 1.54, a melting point of (839±2)°C, and a boiling point of 1484°C. In terms of solubility, it dissolves readily in acids and liquid ammonia, is slightly soluble in alcohol, and insoluble in benzene.
The purity of calcium metal directly affects its surface stability: higher purity results in slower darkening when exposed to air. When heated intensely in air, it burns to form calcium oxide and calcium nitride. At temperatures above 400°C, it reacts slowly with hydrogen to produce calcium hydride. At room temperature, its reaction with water is moderate, forming a calcium hydroxide protective film; however, this reaction becomes violent when heated, releasing hydrogen gas. Due to its strong reducing properties and high chemical activity, calcium easily combines with halogens, sulfur, nitrogen, and other elements, and can reduce almost all metal oxides when heated. It is also a flammable substance that requires proper handling.
Safety & Regulatory Information
For safe handling and usage of calcium metal, it is essential to adhere to the following safety guidelines and regulatory information:
| Item | Details |
| CAS Number | 7440-70-2 |
| EINECS Number | 231-179-5 |
| Molecular Weight | 40.078 |
| InChI | InChI=1/Ca |
| Dangerous Mark | F – Flammable |
| Risk Term | R15 – Contact with water releases extremely flammable gas |
| Safety Terms | S24/25 – Avoid contact with skin and eyes; S43C – In case of fire use limestone powder, sodium chloride, or dry sand (never use water); S8 – Keep the container dry |
Applications of Calcium Metal
The primary application of pure calcium metal lies in steelmaking. Owing to its strong chemical affinity for oxygen and sulfur, it effectively removes these impurities from steel. When calcium combines with oxygen and sulfur, it forms liquid lime, aluminate, and sulfide inclusions that rise to the surface of the molten steel. These inclusions disperse evenly and become small, spherical particles during processing, improving the castability, cleanliness, and overall mechanical properties of the steel.
Beyond steelmaking, calcium metal has a wide range of other industrial applications, including:
It functions as a deoxidizer that binds with carbon, sulfur, phosphorus, and nitrogen in the manufacturing of high-quality steel and non-ferrous metal alloys; it is used as a desulfurizer and decarburizer for iron and ferroalloys; it serves as a separation material for nitrogen-argon gas mixtures; it acts as an oil and gas purifier in the oil and gas industry; it functions as a dehydrating agent for organic solvents; it is used as a getter in the production of electron tubes; it serves as a filler for calcium cored wire; it acts as a raw material for the production of lead-calcium alloys in the battery industry; and it finds applications in the medical and construction sectors.
Production Methods of Calcium Metal
The production of calcium metal involves three main methods: reduction, electrolysis, and calcium refining. Due to its high chemical activity, calcium was traditionally produced via electrolysis of molten calcium chloride or calcium hydroxide. In recent years, the reduction method has gradually become the primary production method due to its cost-effectiveness and higher product quality.
Reduction Method
The reduction method typically uses limestone as the raw material, which is calcined to produce calcium oxide. Aluminum powder is used as the reducing agent. After crushing, the calcium oxide and aluminum powder are mixed in a specific ratio and pressed into blocks. These blocks undergo a reaction under vacuum conditions and high temperatures to generate calcium vapor and calcium aluminate. The calcium vapor is then condensed into crystalline calcium, which is melted and cast into calcium ingots.
Electrolysis Method
The earliest electrolysis method for calcium production utilized the contact principle, which was later improved to liquid cathode electrolysis. The contact method had several drawbacks, including high raw material consumption, high solubility of calcium metal in the electrolyte, low current efficiency, and low product quality.
The liquid cathode method uses a calcium-copper alloy (containing 10%-15% calcium) as the liquid cathode and a graphite electrode as the anode. Electrolytic calcium is deposited on the cathode. The electrolytic cell is made of cast iron, and the electrolyte is a mixture of CaCl2 and KCl. Copper is selected as the alloy component of the liquid cathode because the copper-calcium phase diagram features a wide range of low melting points in the high-calcium-content region, allowing the preparation of calcium-copper alloys with 60%-65% calcium at temperatures below 700°C. The calcium-copper alloy produced via electrolysis is subjected to vacuum distillation to obtain pure metallic calcium.
Calcium Refining
High-purity calcium can be obtained by subjecting industrial calcium to a high-vacuum distillation process. Generally, the distillation temperature is controlled at 780-820°C, and the vacuum degree is 1×10-4. However, distillation treatment is less effective in purifying chloride impurities in calcium. To address this, nitrogen can be added to form double salts when the temperature of the distillate is lower than that of the distillation residue. By adding nitride and performing vacuum distillation purification, the total content of impurity elements such as chlorine, manganese, copper, iron, silicon, aluminum, and nickel in calcium can be reduced to 1000-100ppm, resulting in high-purity calcium with a purity of 99.9%-99.99%.