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Name : Muhammad Insan Kamil

Class : III MA

Nim : 061230200091

Majoring : Mechanical Engineering

Subject : Mechanic of Material

Lecturer : H. Firdaus ST, MT

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Heat Treatment (Perlakuan Panas)

Heat Treatingdefined as the controlled heating and

cooling of metals for the primary purpose of altering their

properties (strength, ductility, hardness, toughness,machinability, etc

Can be done for Strengthening purposes such as

:converting structure to martensite.

Can be done for Softening and Conditioning Purposes

such as : annealing, tempering, etc.

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CASE HARDENING

When we want to make a material harder on the case

(just surface) than in of material.

Low carbon steels cannot be hardened by heating due

to the small amounts of carbon present.

Case hardening seeks to give a hard outer skin over a

softer core on the metal.

The addition of carbon to the outer skin is known as

carburising.

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Function OF Case Hardening

In general case, every part of machinehas a characteristics. so there are some

differences to the needs of the materialsuch as harder output than input.Example :

Gearbox, gear are part of the machine that

works more harder in the surface, so, for makematerial is not brittle & easier break. Thesolution is case hardening

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CASE HARDENING METHODS Methods to Surface Hardening

Heat Treatment

Induction

Flame

Laser

Light

Electron beam

Case Hardening

Carburizing

Cyaniding

Carbonitriding

Nitriding

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Simple process of Surface Hardening

The simple process of surface hardening when

the case of material is heating quickly to more

recrystallization or what we need than itsmaterial is cooling quickly according for what

the material we need.

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Quenching media for Surface Hardening

Brine (water and salt solution)

Water

OilAir

Turn off furnace

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Flame Hardening

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Carburizing

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Pack carburising

The component is packed

surrounded by a carbon-rich

compound and placed in the

furnace at 900 degrees.

Over a period of time carbon

will diffuse into the surface of

the metal.

The longer left in the furnace,the greater the depth of hard

carbon skin. Grain refining is

necessary in order to prevent

cracking.

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Salt bath carburising.A molten salt bath (sodium

cyanide, sodium carbonate and sodium chloride) has

the object immersed at 900 degrees for an hour

giving a thin carbon case when quenched.

Gas carburising.The object is placed in a sealed

furnace with carbon monoxide allowing for finecontrol of the process.

Nitriding.Nitrides are formed on a metal surface in a

furnace with ammonia gas circulating at 500 degrees

over a long period of time (100 hours). It is used forfinished components.

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Aplication of Materials:

Automobile: oil pump gear, drive worm screw,

brake cam, speed box gear

Motor cycle: gears, shaft, pin

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Thank You for Your Attention