Difficult Galvanizing Engineer Interview Preparation Guide

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Because it has more compressive strength and negligible shrinkage. It can easily cast into any integral shape, wear resisting and can absorb vibrations.

It is an alloy steel which contains mainly 8% Nickel and 18% Chromium. Stainless steel main applications in measuring and surgical instruments.

Specific Gravity . It is the ratio of the mass of 1cubic cm. of a substance to the mass of the same capacity of water.
Tenacity .It is the property of metal due to which a metal becomes strong enough to resist the pulling force.

According to carbon percentage
☛ Low carbon steel : Less than 0.25% carbon
☛ Medium carbon steel: 0.25%­0.7% carbon
☛ High carbon steel: 0.7%­1.5% carbon

According to percentage of alloying elements
☛ a. Low alloy steel: Alloying element less than 8%
☛ b. High alloy steel: Alloying element more than 8%

If carbon content is higher the degree of hardness is more and the melting point is lower, If carbon percentage is lower it is easy to forging and forge welding.

To avoid cracks on the part.

It is the property of the metal which makes a metal capable to resist surface penetration by other metals .Hard metals are High carbon steel and High speed steel.

☛ Gun metal is an alloy of 88% copper, 10% tin and 2% zinc. It is generally used for casting boiler fittings, bearings ,bushes etc.
☛ German silver is an alloy of copper, nickel, tin and led. It is used for making utensils and resistances in electrical work.
☛ Duralumin is the aluminium alloy contains 3.5­4.5% copper,0.4­0.7% magnesium,0.4­0.7% manganese and remaining aluminium .Mainly used for making bars, tubes, rivets, sheets ,forgings and stampings.

Malleability is the property of the metal on account of which it can be extended in all directions by hammering or rolling. E.g.: Tin, Lead

Brass is an alloy of copper and zinc. Generally brass contains 60% copper and 40% zinc. These are used for making bearings, pump fittings, bushes and utensils.

Bronze contains copper and tin. It is comparatively hard, surface wear is less, can be remolded into any shape like wires, sheets, rods etc.

Machinability is the property of metal due to which a metal can easily be cut by cutting tools to obtain good surface finish. E.g.: Brass, Mild steel

☛ Babbit metal is a tin base white metal which contains 88% tin, 8% antimony and 4% copper .This is mainly used as a bearing metal.
☛ Bright steel contains 0.05 to 0.45% carbon and up to 0.2%lead.It is used for making set screws, bolts, pins which withstand high loads at longer time.
☛ High speed steel is an alloy of 18% tungsten, 4% chromium,1% vanadium,4%cobalt and 0.7% carbon. This is generally used for making machine tools like lathe ,planer, shaper, taps , drills and milling cutters.

It is the property of metal due to which a metal is capable of resisting deflection due to an externally applied load.

It is a process of making outer surfaces harder of the steel part. Generally it is done for the following purposes,

☛ To make outer surface harder.
☛ To bring the cost cheaper
☛ To utilize low carbon steel.

Babbit metal is a tin base white metal which contains 88% tin, 8% antimony and 4% copper .This is mainly used as a bearing metal.

Process of extraction of iron is called Smelting.

Hardened steel have contains fine grains.

It is the property of metal due to which a metal can be drawn into the form of wires without rupture.

Because it has more compressive strength and negligible shrinkage. It can easily cast into any integral shape, wear resisting and can absorb vibrations.

Bright steel contains 0.05 to 0.45% carbon and up to 0.2%lead.It is used for making set screws, bolts, pins which withstand high loads at longer time.

Heat treatment is an operation involving heating and cooling of metals to change its properties.

It is the property of metal due to which a metal becomes fluid when it is heated.

For easy machining and saving the cutting edge of the tool.

High speed steel is an alloy of 18% tungsten, 4% chromium,1% vanadium,4%cobalt and 0.7% carbon. This is generally used for making machine tools like lathe ,planer, shaper, taps , drills and milling cutters.

Because it resist the heat on the cutting edge of tool and it smoothly work in high speed.