Boron being extremely hard refractory solid of high melting point, low density and very low electrical conductivity, finds many applications.
Boron fibres are used in making bullet-proof vest and light composite material for aircraft. The boron-10 (10B) isotope has high ability to absorb neutrons and, therefore, metal borides are used in nuclear industry as protective shields and control rods.
The main industrial application of borax and boric acid is in the manufacture of heat resistant glasses (e.g., Pyrex), glass-wool and fibreglass.
Borax is also used as a flux for soldering metals, for heat, scratch and stain resistant glazed coating to earthenwares and as constituent of medicinal soaps. An aqueous solution of orthoboric acid is generally used as a mild antiseptic.
Aluminium is a bright silvery-white metal, with high tensile strength. It has a high electrical and thermal conductivity. On a weight-to-weight basis, the electrical conductivity of aluminium is twice that of copper.
Aluminium is used extensively in industry and everyday life. It forms alloys with Cu, Mn, Mg, Si and Zn.
Aluminium and its alloys can be given shapes of pipe, tubes, rods, wires, plates or foils and, therefore, find uses in packing, utensil making, construction, aeroplane and transportation industry.
The use of aluminium and its compounds for domestic purposes is now reduced considerably because of their toxic nature.