CALCIUM BORIDE Property

Melting point:

2235°C

Density 

2.3 g/mL at 25 °C(lit.)

form 

Powder

Specific Gravity

2.3

color 

refractory solid

Resistivity

222 (ρ/μΩ.cm)

Water Solubility 

Insoluble in water. Dissolves slowly in acids

Crystal Structure

Cubic a = 413.77 pm D2 , cP7, Pm3m 1 CaB type (Z = 1)

CAS DataBase Reference

12007-99-7(CAS DataBase Reference)

EPA Substance Registry System

Calcium boride (CaB6), (OC-6-11)- (12007-99-7)

Safety

Hazard Codes 

Xi

Risk Statements 

36/37/38

Safety Statements 

26-36

WGK Germany 

3

TSCA 

Yes

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H315Causes skin irritation

H319Causes serious eye irritation

H335May cause respiratory irritation

Precautionary statements

P261Avoid breathing dust/fume/gas/mist/vapours/spray.

P304+P340IF INHALED: Remove victim to fresh air and Keep at rest in a position comfortable for breathing.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

P405Store locked up.

CALCIUM BORIDE Chemical Properties,Usage,Production

Description

Typical samples of CaB₆ are nonstoichiometric, i.e. the ratio of boron to calcium is not exactly 6:1, for example the ultra-fine powders of CaB₆ produced by some researchers had B:Ca ratio of 5.91:1. It is an important material due to its high electrical conductivity, hardness, chemical stability, and melting point.

Chemical Properties

black cub; -200 mesh 99.5% pure; refractory material [KIR78] [CER91] [CRC10]

Physical properties

Calcium boride is a black, lustrous, chemically inert powder with a low density. Calcium hexaboride is insoluble in H₂O, MeOH (methanol), and EtOH (ethanol) and dissolves slowly in acids. It has the cubic structure typical for metal hexaborides, with octahedral units of six boron atoms combined with calcium atoms.

Uses

Carbon hexaboride is used in the manufacturing of boron-alloyed steel. Also, calcium hexaboride is used as a deoxidation agent in production of oxygen-free copper, which results in higher conductivity than conventionally phosphorus-deoxidized copper owing to the low solubility of boron in copper. Also, it can serve as a high temperature material, surface protection, abrasives, tools, and wear-resistant material.

Uses

Calcium boride is used as an electrode (cathode) material and n-type thermoelectric materials. It is used to make boron- alloyed steel, as a deoxidation agent in the production of oxygen-free copper. It is further used as an antioxidant in carbon bonded refractories. It acts as a new material which is used in the nuclear-industry for neutron- preventing, high-purity metal borid (TiB2,ZrB2,HfB2) and high-purity boron alloy(Ni-B, Co-B, Cu-b).

Preparation

Calcium boride can be formed directly from the elements. Ca melts at 842°C and boron melts at 2076°C. Therefore, if a vapor of Ca metal at >850°C (red-heat) is passed over crystals of boron, a gas–solid reaction forms the desired boride. However, to obtain stoichiometric compositions, it is better to heat the well-mixed powders of Ca and B to obtain specific compounds:
Ca+ 6B→CaB₆

Flammability and Explosibility

Not classified