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

Thermodynamics, discus the method to finding the width of impeller blades i...

discus the method to finding the width of impeller blades in a rotary air compressor

Laser surface treatment applications, LASER SURFACE TREATMENT APPLICATIONS ...

LASER SURFACE TREATMENT APPLICATIONS   The laser can be used to alter the surface structure of materials either with or without alloying additions as compared to alloying by

Hardenability of steel, The hardened layer depth is the measure of harden-a...

The hardened layer depth is the measure of harden-ability. A good harden-ability will sense even thicker sections are uniformly hardened. Conversely a poor harden-ability will gene

What are methods used in rating for time study, a)What are methods used in ...

a)What are methods used in rating for time study. Illustrate them. b) Write down principles of motion economy.

Can you illustrate sea coal, Q. Can you illustrate Sea Coal? Sea coal o...

Q. Can you illustrate Sea Coal? Sea coal or coal dust is finely ground soft coal (pulverized coal). It is added to moulding sand used to make ferrous castings. It tends to obta

Explain the bar chart of hydrostatic sensor paver machine, To select the pr...

To select the project, if not already done. Due to above Problem's in Hydrostatic sensor paver machine, now the select the project and solves the problems and also the cost eff

Determine the maximum bending moment, Design the bending moment and shear f...

Design the bending moment and shear force diagram for a simply supported beam of length 9 m and carrying a Uniformly distributed load of 10 KN /m for a distance of 6 m from the lef

Environments can cause deterioration of foundation, Environments can cause ...

Environments can cause deterioration of foundation. Can you explain this in the following cases? a) A column footing which was stable for a number of years suddenly gave way. T

How do we adjust throttle free play?, (a) What is the function of a throttl...

(a) What is the function of a throttle valve? Where it is used? (b) How do we adjust throttle free play?

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