Light Alloys

In order to cut launching costs and increase pay load capabilities, new satellite systems rely on advanced light alloys with lower densities and equivalent or superior properties compared to the conventional alloys. Aluminium and magnesium alloy castings are widely used in aerospace and other critical defence systems due to their lightweight, near-net shape capability and moderate strength. World-wide there is euphoric interest in exploiting the potential of a host of ultra light, ultra stiff Al-Li and Mg alloys for aerospace applications. Every unit addition of Li to Al offers 3 per cent weight reduction and 6 per cent enhancement in elastic modulus.

The high reactivity of molten Al and Mg alloys and their proneness to micro-shrinkage, inclusions and gas porosity require specialized melting techniques and casting design capabilities to be established. Some of the products developed at DMRL include Wing Bay Casting, Shell (warhead), Compressor Volute Casing and Mounting Case.

Mountaineering Accessory—Carabiner

Mountaineering is not only an adventure sport but also one of the most dangerous war-time operations. Whether in sports or in war, life of a mountaineer depends on very small accessories and Carabiner is one of them. It is a lightweight (about 85 g) accessory that is designed to carry high loads and provide for the ready insertion, removal and safe retention of the climbing rope. The Carabiner is made up of many small components such as the body, lever, spring, pin, screw and rivets. DMRL has developed Carabiner with and without screw (for additional locking) types weighing 80-85 g using aluminium alloy DTD 5124 extruded rod (diameter 14 mm). These are under production at Ordnance Factory, Dehradun.