The limitations of plain carbon steels include

Explanation:

Plain carbon steels:

Plain carbon steel is a type of steel having a maximum carbon content of 1.5% along with small percentages of silica, sulphur, phosphorus, and manganese. Carbon steel is made into a wide range of products, including structural beams, car bodies, kitchen appliances, and cans.

Classification of carbon steel

Low Carbon Steel (Mild Steel):

• Low carbon steel is an alloy of iron and carbon. The carbon content varies from 0.05 to 0.15 % for dead mild steel and 0.15 to 0.3 % for mild steel.
• The dead mild steel is very much ductile and is used for making various components like sheets, strips, wires, rods etc.
• The mild steel is soft and ductile.
• It is used for making various structural sections like angles, channels, beams, rods, pins, etc.

Medium carbon steel:

• For medium carbon steel, the carbon percentage varies from 0.3 to 0.8%.
• These steels have better strength and not very easy to shape as mild steel.
• The hardness is slightly higher, and the ductility is poor.
• The machine parts requiring strength like springs, automobile parts, shafts, dies for forging etc. are made from medium carbon steel.

High Carbon steel:

• The carbon percentage varies from 0.8 to 1.5.
• A high percentage of carbon gives hardness and strength to the metal.
• It is mainly used for tools like chisels, hammers, dies, punches, broaches, reamers, drills, taps, etc. and the machine parts like springs, mandrels and similar parts requiring high strength and hardness.

Limitation of carbon steel

• Low hardenability
• low corrosion and oxygen resistance
• Major loss of hardness on tempering