Whenever we can talk about the property that helps the metals to deform at that time these two properties first comes to our mind. Malleability and ductility are both of them are two similar properties but they have many differences between them.
What is Malleability?
Malleability is defined as the ability of a material to deform to a greater extent before the sign of a crack when it is subjected to a compressive force.
What is Ductility?
Ductility is defined as the ability of a material to deform to a greater extent before the sign of a crack when it is subjected to a tensile force.
Let us have a deep insight into the comparison between malleability and ductility.
Difference between malleability and ductility :
- Malleability is the ability of a material to deform under compressive force while ductility is the ability to deform under tensile force.
- All ductile materials are also malleable, but the converse of that is not true.
- Malleability increases with temperature while ductility decrease with increasing temperature.
- With hammering or rolling without fracture, a malleable material can be shaped with plastic, while ductile materials can usually be elongated with more than 15% before fracturing.
- Malleable material can be rolled into sheets while ductile can be rolled into the wire.
- Malleability is an important property when the component is forged, rolled or extruded while ductility is desirable when the components are formed or drawn and also when components are subjected to shock loads that is a good property of ductility.
- Both malleability and ductility are reduced by the presence of impurities in the metal.
- Malleable materials are mild steel, gold, lead while ductile materials are copper, mild steel and thermoplastics.
- Lead has high malleability, with low ductility.
- Malleability is affected by the crystal structure and ductility is affected by the grain size.
- Test for measured malleability is the ability to withstand pressure while ductility by the bend test.
Notes :
Most ductile materials are malleable.
Gold is both highly ductile and malleable that is the main reason that it is used in making jewellery.
Malleability and ductility of metals can be accounted for due to their presence of elastic forces While malleability and ductility are both characteristics of substance with metals.