Quenching and tempering, Mechanical Engineering

Assignment Help:

Quenching and Tempering

Cast iron pearlite structure might be heated to lower critical temperature and after that quenched to effect extremely rapid cooling. This treatment reasons the precipitation of hard martensite phase and casting is hence capable of giving high wear resistance. The casting behind quenching treatment might be further heated to 300oC and cooled gradually to restore original toughness.

Surface Hardening

A lot of applications of cast iron demand high surface hardness. This might be attained by surface hardening treatments as like: induction and nitriding hardening.

Table: Typical Mechanical Properties and Applications of Cast Iron

 

Cast Iron

Composition wt. %

Condition

Structure

UTS MPa

YS MPa

Elongation

(%)

Typical Application

 

 

Gray Cast

Iron

Ferrite

3.4 C,

2.2 Si,

0.7 Mn

Annealed

Ferrite matrix

180

-

-

Cylinder blocks and head clutch plates

Pearlite

3.2 C,

2.0 Si,

0.7 Mn

As-cast

Pearlite matrix

250

-

-

Truck and tractor cylinder blocks, gear box

Pearlite

3.3 C,

2.2 Si,

0.7 Mn

As-cast

Pearlite matrix

290

-

-

Diesel engine castings

 

 

Melleable

Cast Iron

Ferrite

2.2 C,

1.2 Si,

0.75 Mn

Annealed

Temper carbon and ferrite

345

224

10

General engineering service machinability

Pearlite

2.4 C,

1.4 Si,

0.75 Mn

Annealed

Temper carbon and pearlite

440

310

8

General service with dimensional tolerance

Martensitic

2.4 C,

1.4 Si,

0.75 Mn

Quenched and Tempered

Tempered martenstie

620

438

2

High strength parts, connecting rods, yokes for universal joints

 

 

Ductile

Cast Iron

Ferrite

3.5 C,

2.2 Si

Annealed

Ferritic

415

275

10

Pressure casting as valve and pump bodies

Pearlite

3.5 C,

2.2 Si

As-cast

Ferritic pearlite

550

380

6

Crank shaft, gears and rollers

Martensitic

3.5 C,

2.2 Si,

Quenched and Tempered

Martensitic

830

620

2

Pinions, gears, rollers and slides

 

 


Related Discussions:- Quenching and tempering

Tank drainage-apparent viscosity-laminar flow, Tank Drainage A large op...

Tank Drainage A large open vertical tank has three small, smooth, well-rounded orifices spaced equidistantly at ¼ h , ½ h , ¾ h up from the bottom of the tank (Fig. Q1). Water

Mash stitch welding, Mash stitch welding An overlap of about 1.15 mm is...

Mash stitch welding An overlap of about 1.15 mm is kept and then the plates are squeezed flash by application of pressure at hot condition.  Mash stitch welding is used in the

Overhead bridge crane, Overhead Bridge Crane Figure below shows a jib cr...

Overhead Bridge Crane Figure below shows a jib crane. In this type of crane the hook can move in a circular path. A jib crane is preferred where lifting of the jobs is requ

Laser-induced breakdown spectroscopy , Laser-induced breakdown spectroscopy...

Laser-induced breakdown spectroscopy (LIBS) is a type of spectroscopy that uses plasma generated by a laser pulse. A schematic of a LIBS system is shown in the figure. The laser is

Explain the procedure of rockwell hardness tests, Q. Explain the procedure ...

Q. Explain the procedure of Rockwell hardness tests? Rockwell hardness tests per ASTM of the deposited weld, and heat affected zone shall be required for procedure qualificatio

Globular transfer, Globular Transfer Globular transfer  is characterise...

Globular Transfer Globular transfer  is characterised by a drop size of greater diameter than that of the electrode wire. The large drop is easily acted on by gravity, generall

Define milling cutter - geometry of cutting tool, Define Milling Cutter - G...

Define Milling Cutter - Geometry of Cutting Tool Out of large verity of milling cutter used in milling cutter used in milling practice, two types of cutter chosen to describe t

How is aluminium conductor steel reinforced used, ACSR (Aluminium Conductor...

ACSR (Aluminium Conductor Steel Reinforced) are used as  (A)  over head transmission lines.  (B)  super conductors. (C)  fuse  (D)  underground cables.

What do you understand by straight line mechanism, What do you understand b...

What do you understand by straight line mechanism ? Describe with a neat sketch the working and construction of any three types of straight line mechanism. Derive a mathematical

Copper-nickel alloys, Copper-Nickel Alloys Complete solubility arises ...

Copper-Nickel Alloys Complete solubility arises between nickel and copper. All alloys have same microstructure and may be cold or hot worked. Cupro-nickel also termed as Ge

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd