What is an alloy? Give three reasons why alloys are made.
An alloy is a uniform combination of two or more metals or a metal with a non-metal. Alloys usually have different properties from those of pure metal. They have some special features when compared with pure metals.
Disclaimer: Any three of the below mentioned characteristic features of alloys can be used to answer the given question.
The characteristic features of alloys are
1. Alloys differ in their chemical reactions as compared to pure metals. For example, iron corrodes in moist air but stainless steel, which is an alloy of iron and carbon, does not corrode at all.
2. Alloys have better tensile strength as compared to pure metals. For example, duralumin, which is an alloy of aluminium, is very strong as compared to aluminium.
3. Alloys have better hardness as compared to pure metals. For example, carboloy, which is an alloy of tungsten, copper and cobalt, is very hard (like diamond) as compared to its constituent metals.
4. Alloys have better appearance and colour than their constituent metals. For example, aluminium bronze an alloy of aluminium and copper has an appearance that resembles gold metal.
5. Certain alloys can be easily cast. For example, type metal an alloy of lead, tin and antimony can be easily cast and it expands on heating.
6. Alloys have different melting points than pure metals. For example, solder an alloy of lead and tin has a melting point (180oC) which is lower than the melting point of either metal (Pb - 327.5oC and Sn - 232oC).
7. Alloys have better electrical resistivity than pure metals. For example, nichrome (an alloy of nickel and chromium) is more resistant to electric current than nickel and chromium.
8. Alloys are more sonorous than pure metal. For example, bell metal (an alloy of copper and tin) is more sonorous than pure metals.
9. Alloys have enhanced magnetic properties. For example, alloy of aluminium, cobalt and nickel, alnico is more magnetic than pure metals.
An alloy is a uniform combination of two or more metals or a metal with a non-metal. Alloys usually have different properties from those of pure metal. They have some special features when compared with pure metals.
Disclaimer: Any three of the below mentioned characteristic features of alloys can be used to answer the given question.
The characteristic features of alloys are
1. Alloys differ in their chemical reactions as compared to pure metals. For example, iron corrodes in moist air but stainless steel, which is an alloy of iron and carbon, does not corrode at all.
2. Alloys have better tensile strength as compared to pure metals. For example, duralumin, which is an alloy of aluminium, is very strong as compared to aluminium.
3. Alloys have better hardness as compared to pure metals. For example, carboloy, which is an alloy of tungsten, copper and cobalt, is very hard (like diamond) as compared to its constituent metals.
4. Alloys have better appearance and colour than their constituent metals. For example, aluminium bronze an alloy of aluminium and copper has an appearance that resembles gold metal.
5. Certain alloys can be easily cast. For example, type metal an alloy of lead, tin and antimony can be easily cast and it expands on heating.
6. Alloys have different melting points than pure metals. For example, solder an alloy of lead and tin has a melting point (180oC) which is lower than the melting point of either metal (Pb - 327.5oC and Sn - 232oC).
7. Alloys have better electrical resistivity than pure metals. For example, nichrome (an alloy of nickel and chromium) is more resistant to electric current than nickel and chromium.
8. Alloys are more sonorous than pure metal. For example, bell metal (an alloy of copper and tin) is more sonorous than pure metals.
9. Alloys have enhanced magnetic properties. For example, alloy of aluminium, cobalt and nickel, alnico is more magnetic than pure metals.
