Foundry materials

Raw material for foundry is

a)      Metals and alloys

b)      Fuels (for melting metals)

c)      Fluxes

d)     Refractory

Aluminium based casting alloys:

1)      Si 8 to 13%, Mg 0.17 to 0.3%, Mn 0.250 to 0.5% and reminder aluminium.

This alloy is used for making large castings which have to work under heavy duty loading conditions. This alloy possesses high corrosion resistance and can be easily machined.

2)      Al (9.5 to 11.5%) Mg alloy

Simple castings which are subjected to dynamic loading and which work in corrosive atmosphere are made up this alloy.

3)      Al-Si-Ca alloys containing 4.5 to 6% Si, 1 to 3% Cu, 0.35 to 0.65 Mg and remainder aluminium possesses good castability. They can be molded in sand or permanent moulds. These castings can severely loaded and can work at high temperatures.

4)      A few other aluminium castings alloys are:

a)      Al (4.5%) Mg and (0.5%) Mn alloy

b)      Al (4.5%) Cu alloy

c)      Al (4%) Cu,(2%) Ni

d)     (1.5) Mg alloy.   Etc.

Uses of aluminium alloys:

1)      In transportation industry: structural framework

Engine parts

Trim and decorative parts / features

Hardware

Doors

Window frames

Tanks

Furnishing and fitting

Train, truck, bus, automobile cars and aero planes use many components parts made up of aluminum alloys.

2)      Overhead cables and heat exchanger parts.

3)      In food industry (pan etc.), refrigeration, storage container, bakery equipments, shipping containers. Etc.

4)      Mangles and waffle molds.

5)      In architectural fields.

6)      Cryogenic application.

7)      Dragline booms, travelling cranes, hoist, conveyors supports, bridges etc.

8)      In process industries, parts made up of aluminium and its alloys are used to handle organic chemicals, petrochemicals and drugs, tanks, drums, pipes, heat exchangers, grating, smokestacks, drilling tower, precipitators, centrifuges, valve fittings etc.

Cryogenic – study of very low temperature.

Grating – a grid of metal bar over an opening.

A flux – is a low melting materials

            -Limestone – cupola furnaces- cast iron.

            -Sodium carbonate

            -Nitrogen, helium and chlorine – gaseous fluxes- aluminium industry-    for  removing               dissolved hydrogen, dross.

Mangles – a machine with rollers for wringing out wet laundry

Refractory –   -     heat resistant materials

-          Can withstand high temperature without being fused.

-          Crucible and furnaces sides and bottom containing molten metals are made up of refractories.