Wednesday, December 3, 2008

NDT Metal/Ductility & Brittleness

Original Metal
Read carefully following ratio about to know Ductile / Brittleness in an original metal

Ductile Brittleness

L.C.S. 80 % 20 %

M.C.S 70 % 30 %

H. C. S 60 % 40 %

After welding 30% brittleness arises

L.C. S 50 % 50 % Ductility 100%

M.C.S 40 % 60 % V. Difficult welding

H.C.S 30 % 70 % Welding Impossible


Note:- Brittleness is reduced by stress reliving process
What is the Application of Tempering, Normalizing and Annealing? Read carefully following points to know about them:
1- Tempering

Removal of surface stresses by heating from 200c ~ 500c. This process does for removing surface cracks only.

2 Normalizing
Normalizing removes Internal and external stress.
For this application will have to heat of a metal on high degree than tempering process. Example: if tempering temperature is 900c to 1100c so, normalizing temperature will be from 900c to 1250c.

3- Annealing
Procedure will be same like Normalizing but it takes 15minutes per square inch/- than normalizing. After this application metal will be 100% ductile.
_____________________________________________________________________
What is Polycarbonate?

Answer: Poly carbonate is a shield which use for making glass for bullet proof cars. During processing of glass making both sides of a glass has been covered by this sheet.
How do you evaluate carbon ratio in a metal?

Original Hardness : % age of Carbon

0 ~ 5 HRC % 0.25% L.C.S

5 ~ 10 % 0.50% M.C.S

10 ~ 18 % 1.20% H.C.S

After heat treatment Hardness is increased if from 45 ~ 60 HRC metal is 50% Brittle and 50% Ductile.

If variation in Hardness is from + 4 ~ + 10 HRC metal is highly metallic and under high stress. ~ ~

AFTER WELDING

Ductile Brittleness

M.C.S 40: 60% only stresses reliving

H.C.S 30: 70%

50 50% only pre-heat or 100%
Post heat strong

50 50% Pre bath heat & post heat





Heat Treatment Phases
1500c~ 1600c below melting point (A-1) (Cold water) (L.C.S)
Stainless steel is highly ductile it is ferrite.

900 ~ 1100c pearlite (A-2) (Quenching Oil) (M.C.S)
Fine grain closed pack

Pear light slow cooling cement-tite (A-3) (Air) ( H.C.S)

A1 A3 transformation

Pear light slow cooling cementtite




Rapid Cooling




Hard Martin site (FEC)


What is Banite?

Banite is slightly more brittle and hard compared with cementtite.

For cutting soft material like (Shaving blade, File Blade)


Posted by: Irfan

NDT Metal Composition Analyzer

What is the florescent light?

Application: This use for checking cracks especially in Railway Engine wheel.

Method: Firstly we spread black ink at specific area of the wheel then we apply light and all cracks shown on the wheel.


What is the Probe?

Application: Probe consists on two nobs wire. It use for checking cracks in a building. Through this you can see cracks from 8” Inches to 100 f/t. it especially uses for buildings.

Method: For this a Technician use a Crain for lifting up him and check cracks through prode. This application is applicable on macro.

What is the metal composition analyzer?

Low: 0 – 5 C Scale

Medium: 7 – 10 C Scale

High: 10 – 18 C Scale

What is the hardness of steel?

Low: 0.25%

Medium: 0.50%

High: 1 and 2%


What is T M C P ?

T: Thermo

M: Mechanical

C: Control

P: Process

Application of the mechanical force on the work piece to get ready by distortion and stresses.
Edge and extreme ends + holes and cauities are the major areas where stress & distortion is more concentrated & higher.

Posted by: Irfan

NDT Metal Composition Analyzer

What is the florescent light?

Application: This use for checking cracks especially in Railway Engine wheel.

Method: Firstly we spread black ink at specific area of the wheel then we apply light and all cracks shown on the wheel.


What is the Probe?

Application: Probe consists on two nobs wire. It use for checking cracks in a building. Through this you can see cracks from 8” Inches to 100 f/t. it especially uses for buildings.

Method: For this a Technician use a Crain for lifting up him and check cracks through prode. This application is applicable on macro.

What is the metal composition analyzer?

Low: 0 – 5 C Scale

Medium: 7 – 10 C Scale

High: 10 – 18 C Scale

What is the hardness of steel?

Low: 0.25%

Medium: 0.50%

High: 1 and 2%


What is T M C P ?

T: Thermo

M: Mechanical

C: Control

P: Process

Application of the mechanical force on the work piece to get ready by distortion and stresses.
Edge and extreme ends + holes and cauities are the major areas where stress & distortion is more concentrated & higher.

Posted by: Irfan

Tuesday, September 16, 2008

What is Non Destructive Testing ?

Non Destructive Testing is an art through this technology you can check invisible cracks and flaws which can be danger in future and present.