MATERIAL SCIENCE
HEAT TREATMENT
MATERIAL
O Metals
O Non - Metals
O Plastics
O Ceramics
O Composites
METALS
O FERROUS
-
Steel
- Cast Iron
O NON FERROUS
Aluminium, Titanium
Nickel, Cobalt
Copper
O Other than IRON all other metals
-
IRON IRON-CARBON DIAGRAM
Eutectic
eutectoid
Pearlite and
Cementine
Austenite
Ferrite
Pearlite and
Carbide
Pearlite
Steel
Cast iron
Microstructure of different phases of steel
STEEL
Steel is an alloy of Iron and Carbon. The
percentage of carbon in steel varies and the
maximum limit is 1.9%
Steel is generally classified as:
O Plain Carbon Steel
O Alloy Steel
Plain Carbon Steel
O Low Carbon Steel/Mild Steel (upto 0.3%C)
O Medium Carbon Steel (0.3 - 0.6% C)
O High Carbon Steel (0.6 - 1.2% C)
Plain Carbon Steel
Examples:
O Low Carbon Steel/Mild Steel
O WCB/WCC – ASTM A216
O LCB/LCC – ASTM A352
O LF2 – ASTM A350
O A105 – ASTM A105
O A106 – ASTM A106
O Medium Carbon Steel
O EN 8 – BS 970
O High Carbon Steel
O Spring steel, Rail steel – ASTM A313
ALLOY STEEL
Steel contains more than 5.0% alloying elements like
Mn, Cr, Ni, Mo, V which are intentionally added to
improve specific properties.
Example : Tool steel, Stainless Steel
ALLOY STEEL
O Low Alloy Steel (0 - 5 % alloying element)
O Medium Alloy Steel (5 - 10%)
O High Alloy Steel (more than 10%)
LOW ALLOY STEEL
O WC6 / F11 / P11
O WC9 / F22 / P22
O EN19 / AISI 4140
O 60K
 ASTM A217 – Casting
 ASTM A182 – Forging
 AISI 4140 – Bar
 ASTM A487
PROCESSES
O Moulding & Casting (Foundry)
O Hot Working Process
O Forging
O Hot Rolling
O Cold Working Process
O Welding
O Powder Metallurgy Process
METAL FORMS
O CAST FORM
- Ingot
O WROUGHT FORM
- Billet
- Bars, Rod, Wire
- Plate, Sheet, Strip
O POWDER FORM
STAINLESS STEEL
O Domestic name is Ever-Silver
O Cr content not less than 11%
O Cr forms thin, protective oxide layer on the surface,
which prevents further oxidation.
STAINLESS STEEL
Stainless Steel are classified as:
O Ferritic SS:
AISI 430
O Austenitic SS
:
316, CF8M
O Martensitic SS :
410, 416, 420
O PH SS
:
17-4 PH, Cb7 Cu1
O Duplex SS :
4A
O Super Duplex SS:
5A , 6A
O Super Austenitic SS: 904L, 254SMO
STAINLESS STEEL
Stainless Steel are classified as:
ASTM A351, CF3, CF3M, CF8, CF8M – Casting
ASTM A182 – F304L, F316L, F304, F316 – Forging
ASTM A276, A479 – Type 304, 304L, 316, 316L – Plate
ASTM A564- 17-4 pH
ASTM A747 – Cb7 Cu1 Casting
ASTM A890, A995 – 4A, 5A, 6A ; F51 . F55 - Bar
ASTM B625
CAST IRON
Alloys of Iron and Carbon with more than 2.11%
Carbon are called Cast Irons
O SG (Spheroidal Graphite) Iron : SG 400/15
O Ni Nodular Resist Iron
O Grey Cast Iron
O Alloy Cast Iron
O Malleable Iron
: NNR
: BS 1452 Gr. 220
: AUDCOALLOY
: IS 210 8 BM 340
HEAT TREATMENT
A combination of heating and cooling operation,
timed and applied to a metal or alloy in the solid
state in a way that will produce desired properties.
PURPOSE OF HT:
O To obtain homogenous structure, desired mechanical
properties.
O To improve machinability.
O To relieve internal stresses.
HEAT TREATMENT
Types of HT:
O Annealing
O Quanching
O Normalizing
O Hardening
O Tempering
O Stress Relieving
Full Annealing
This process consists of heating the steel to
austenitising temperature (850 - 925 deg C) and
cooling slowly to room temperature to reduce
hardness and improve machinability. Eg: CS, LAS
Solution Annealing
Solution annealing consists of austenitising
stainless steel at 1040 - 1150 deg C and cooling
very fast by quenching in air (or) water.
O Eg: CF8, CF8M, CF3, CF3M, 4A, 5A
Normalizing
Normalizing consists of heating a ferrous alloy
875 - 950 deg C temperature followed by
cooling in still air to room temperature. Eg:
WCB, A105
Normalizing
O To refine grain and homogenous
microstructure.
O Improve machinability.
O To get desired mechanical properties.
Recommended Temperature:
Material
Temperature
A105
900 - 920 deg C
A182 F11, F22
900 - 920 deg C
WCB
900 - 920 deg C
Hardening
Hardening consists of austenitising ferrous alloy
followed by quenching in air, oil (or) water to
increase the hardness.
Purpose:
O To obtain martensitic structure.
O To obtain hardness.
Classified as:
O
O
O
Case Hardening
Age Hardening
Through Hardening
Tempering
Re-heating a quench hardened or normalized
ferrous alloy to a temperature below 720 deg C
and then cooling in still air to obtain desired
mechanical properties and hardness.
Purpose:
O To relieve internal stresses.
O To improve ductility and toughness.
Stress Relieving
Heating to a suitable temperature, holding long
enough to reduce residual stresses, and then
cooling slowly enough to minimize the development
of new residual stresses.
Stress Relieving
PURPOSE:
To remove welding, forging & cold working
stresses.
Material
Temperature
WCB, A105, LCB, LCC,WC6 600 - 640 deg C
A515 Gr.70 & A516 Gr.70
600 - 640 deg C
A182 Gr F1, F11
600 - 640 deg C
A487 Gr. 4A, 4D
620 - 640 deg C
WC9, F22, 410, CA15
675 - 700 deg C
C5, C12
700 - 720 deg C
NON FERROUS
INCONEL
MONEL
Al BRONZE
Al ALLOY
: INCONEL 625
: MONEL 400
: BS 1400 AB 2
: LM 25
MATERIAL PROPERTIES
O Chemical Property
O Physical Property
O Mechanical Property
O Metallurgical Property
CHEMICAL PROPERTY
Chemical composition of the material either in wt% or in
at%.
Some of the chemical elements are as follows:
C, Si, Mn, S, P, Cr, Ni, Mo, Cu, V, Co, W, Al, Ti, Ta, Nb etc
CHEMICAL PROPERTY
Chemical composition of the material is checked by the
following methods:
O Wet Method -
By Titration
O Wet Method using Spectrophoto meter
O Atomic Absorption Spectrometer
CHEMICAL PROPERTY
Wet Method - By Titration
CHEMICAL PROPERTY
Wet Method using Spectrophotometer
CHEMICAL PROPERTY
Atomic Absoption
Spectrometer
- Portable
(or)
PMI
Positive Material
Identifier
CHEMICAL PROPERTY
PMI
OES
Chemical Elements
C : Carbon
Mn: Manganese
S : Sulfur
P : Phosphorous
Si : Silicon
Ni : Nickel
Cr : Chromium
Mo : Molybdenum
V : Vanadium
Cu : Copper
W : Tungsten
Fe : Iron
Chemical Elements
Carbon - Increased amounts of carbon increase hardness and
tensile strength, Carbon content the strength and hardenability
of steel increase but its ductility, forgeability and
machineability reduces
Mn. Manganese - Manganese increases the strength of steel to a
lesser degree than Carbon while it favourably influences the
forgeability, weldability and markedly increases the hardness
penetration depth.
Si. Silicon Silicon is a deoxidiser and promotes graphite
precipitation, it also increases the strength and wear
resistance of steel while significantly increasing the elastic
limit, thus being a useful alloying element in spring steels.
Because of Silicons ability to greatly red
Chemical Elements
S Sulphur - Sulphur is added to steels for automatic
machining in quantities of up to 0.40%. This reduces the
friction on the tool cutting edges by means of lubricating
action. thereby increasing tool life. It also produces
shorter chips during machining. Sulphur also increases
susceptibility to welding cracks in steel.
P. Phosphorus - Phosphorus is normally regarded as being
detrimental to steel and every endeavour is therefore
made to keep Phosphorus content in high grade steels to
a maximum of 0.03 to 0.05%.
Chemical Elements
Cr. Chromium - Chromium increases the hardenability of steel
while the ductility is effected minimally. Higher Chrome content
in steel increases its corrosion resistance, and by forming
carbides the edge holding quality of steel increases. The
tensile strength of steel increases by 8 - 100 N/mm'2 for every
1 % chrome added. The yield strength also increases but the
notch impact value reduces.
Ni. Nickel By adding Nickel to steel the notch toughness is
increased significantly and is therefore alloyed for increasing
toughness in case-hardening, heattreatable and subzero
toughness steels. Nickel combined with Chromium ensures
good through hardening. Chrome-Nickel steels are Stainless,
heat resistant and resistant
Chemical Elements
Mo. Molybdenum - While Molybdenum improves the tensile
strength and increases the heat resistance and weldability of
steel, the forgeability of steel with high molybdenum, content
decreases. When used in combination with Chromium and
Nickel , Molybdenum may produce high yield points and tensile
strength values.
V. Vanadium - Vanadium is used as a primary grain refiner in the
manufacture of steel. It is also a strong carbide former, thus
providing increased wear resistance, edge holding and high
temperature strength. Vanadium is therefore used primarily as
an alloying element in high speed, hot forming and creep
resistant steels
Chemical Elements
Co Cobalt is primarily used as the metal, in the preparation
of magnetic, wear-resistant and high-strength alloys.
Carbon Steel -WCB (Elements in wt%)
C : 0.30 max
Mn
: 1.00
S
: 0.050
P
: 0.040
Si: 0.60
* Trace Elements
Cr : 0.50*
Mo : 0.20*
V : 0.30*
Cu : 0.30*
Ni : 0.50*
Low Alloy Steel ( Elements in wt% ) :
WC6
C : 0.20
Mn: 0.50 - 0.80
S : 0.045
P : 0.040
Si : 0.60
Cr : 1.00 - 1.50
Mo : 0.45 - 0.65
Cu : 0.50
W : 0.10
Ni : 0.50*
Alloy Steel-SS (Elements in wt%) :
CF8M
C : 0.080
Mn : 1.50
S : 0.040
P : 0.040
Cr : 18.0 - 21.0
Mo: 2.00 - 3.00
Ni : 9.00
Si : 1.50
Alloy Steel-SS (Elements in wt%): CF8
C : 0.080
Mn: 1.50
S : 0.040
P : 0.040
Cr : 18.0 - 21.0
Ni : 8.00 - 11.0
Mo: 0.50
Si : 2.00
Alloy Steel-SS (Elements in wt%):
17-4 PH
C : 0.070
Mn : 0.70
S : 0.030
P : 0.035
Nb+Ta: 0.15 - 0.35
Cr : 15.5 - 17.5
Cu : 3.0 - 5.0
Ni : 3.0-5.0
Si : 1.00
Alloy Cast Iron (Elements in wt%)
: NNR( D2)
C : 3.00
Mn
: 0.70-1.25
Cr
: 1.75 - 2.75
Ni: 18.0 - 22.0
P
Si
: 0.080
: 1.00- 3.00
INCONEL (Elements in wt%) :
Inconel 625
C
: 0.10
Mn
: 0.50
S & P : 0.015
Si
: 0.50
Ni: 58.00(min)
Cr
Mo
Fe
Nb
: 20.0 - 23.0
: 8.0 - 10.0
: 5.00 max
: 3.50 -4.15
MONEL ( Elements in % ) :
Monel-400
C : 0.30
Mn
: 2.00
S
: 0.024
Si: 0.50
Cu : 28.0 - 34.0
Fe : 2.50 max
Ni : 63.0 (min)
Stellite#12 ( Elements in % ) :
Ste #12
C : 1.40 – 1.85
Mn
: 1.00
W: 8.50
Si: 1.50
Cr : 29.5
Fe : 2.50 max
Ni : 3.00 max
Co : Rem
Stellite #6 ( Elements in % ) :
ste# 6
Cr
Mo
Ni
W
Co
: 22.75 to 36.00
: 1.125
: 3.38 max
: 2.63 to 6.75
: Rem
Welding ENDS
C : 0.23%
CE : 0.43 %
MECHANICAL TESTING
O Tension Test
O Bend Test
O Hardness Test
O Impact Test
METALLURGICAL TESTING
O Micro Structure Analysis
O Macro Etch Test
O IGCT (Inter Granular Corrosion Test)
O Ferrite Content Test
O Inclusion Rating
O Case Depth Analysis
PHYSICAL TESTING
O DENSITY
O PAINT TESTING
O WATER TESTING
O COATING THICKNESS
TENSION TEST
Strength is defined as load required to cause rupture.
O By UTM (Universal Testing Machine)
Properties:
O Yield Strength (YS) 0.2% offset
O Ultimate Tensile Strength (UTS)
O % Elongation
O % RA (Reduction in Area)
TENSION TEST
Units:
Mpa – Mega pascal
N/mm2 – Newton
Psi – Pounds per square inch
Kgf/mm2 – Kilogram force
kilopound per square inch
HARDNESS TEST
Resistance of metal to plastic deformation usually by
indentation. (or) abrasion, scratching, cutting.
Types of Hardness Test:
O Brinnel
- Ball indenter
O Rockwell
- Diamond cone / Ball
O Vickers
- Pyramid type diamond
O Micro Vickers, Portable etc.,
O ASTM E10
HARDNESS TEST
HRA . . . . Cemented carbides, thin steel and
shallow case hardened steel
HRB . . . . Copper alloys, soft steels, aluminium
alloys, malleable irons, etc
HRC . . . . Steel, hard cast irons, case hardened
steel and other materials harder than 100
HV = Vickers hardness
BHN – Brinell Hardness Test
IMPACT TEST
A test to determine the behavior of materials when
subjected to high rates of loading.
O Charpy & Izod method
O energy absorbed in the broken specimen
O low temperature importance
O Test sample with notches
Inter Granular Corrosion Test
SS are susceptible to IGC (corrosion along the grain
boundary) under certain condition.
O ASTM A262 Practice A , B ( 120 Hrs ) , C( 240 Hrs) , E(24
Hrs).
O ASTM G48
CODES & STANDARD
ASTM - American Society for Testing of Materials
AISI
- American Iron and Steel Institute
ASME - American Society for Mechanical Engineers
ANSI
- American National Standards Institute
API
- American Petroleum Institute
IS
- Indian Standard
BS/ EN - British Standard / Euro Norms
ISS
- Iron and Steel Society
DIN
- German Institute of Standardization
NACE - National Association of Corrosion Engineers
IBR
- Indian Boiler Regulation
MSS-SP-Manufacturers Standardization Society - Standard
AWS
- American Welding Society
Practice
CODES & STANDARD
ASQ
BSI
ISO
UL
- American Society of Quality
- British Standards Institution
- International Organization for Standardization
- Underwriters Laboratories Inc.
Body & Connector – Carbon Steel
• ASTM A216 Gr. WCB – Casting
• ASTM A216 Gr. WCC - Casting
• ASTM A105 - Forging
Body & Connector – Low Temp Carbon Steel
• ASTM A352 Gr. LCB – Casting
• ASTM A352 Gr. LCC - Casting
• ASTM A350 Gr. LF2 - Forging
Body & Connector – Stainless Steel
• ASTM A351 Gr. CF3 – Casting
• ASTM A182 Gr. 304L – Forging
• ASTM A351 Gr. CF3M – Casting
• ASTM A182 Gr. 316L - Forging
• ASTM A351 Gr. CF8 – Casting
• ASTM A182 Gr. 304 – Forging
• ASTM A351 Gr. CF8M – Casting
• ASTM A182 Gr. 316 - Forging
• ASTM A351 Gr. CF8C – Casting
Body & Connector – Duplex & Super
duplex Stainless Steel
• ASTM A890 / A995 Gr. 4A – Casting
• ASTM A890 / A995 Gr. 5A – Casting
• ASTM A890 / A995 Gr. 6A – Casting
• ASTM A182 Gr. F51 – Forging
• ASTM A182 Gr. F55 – Forging
• ASTM A182 Gr. F60 – Forging
Fasteners
STUD & NUT – CARBON STEEL
• ISO 898 Gr.8.8 & 8
• ASTM A193 GR. B7 & ASTM A194 Gr. 2H
• ASTM A193 Gr. B7M & ASTM A194 Gr. 2HM
STUD & NUT – STAINLESS STEEL
• ASTM A193 GR. B8 & ASTM A194 Gr. 8
• ASTM A193 Gr. B8M & ASTM A194 Gr. 8M
Fasteners
STUD & NUT – LOW TEMP CARBON STEEL
• ASTM A193 GR. L7 & ASTM A194 Gr. 7
• ASTM A193 Gr. L7M & ASTM A194 Gr. 7M
• ASTM A 320
STUD & NUT – STAINLESS STEEL DIN SANDARD
• DIN 933 A2 – 70 & DIN 944 A2 - 70
• DIN 933 A4 – 70 & DIN 944 A4 - 70
TC Verification
TC Verification
Material Test certificate for all heat numbers
• Material test certificate format as per EN 10204, 3.1
or 3.2, as per Sale Order / Purchase Order.
• Pouring date and Certification date
• Material standard with latest revision
• Applicable customer specification
• Material Grade as per Sale Order / Purchase Order
requirement
• Foundry Name and Identification
• Item Description and Quantity
• Chemical, Mechanical, Heat treatment and any
other test results as specified in Sale Order /
Purchase Order.
TC Verification
• Statement of compliance to procedures like
• Visual,
• Radioactive contamination,
• Material specification
• Special Requirement as applicable to Sale order
/ Purchase order.
• Endorsement by Foundry QA and TPI for
acceptance for 3.2 certification
• Ferrite , Micro structure Report & IGC Report (If
applicable)
• MPI / DPI reports
• Radiography films (If applicable)
• Radiography evaluation reports (in FICPL format)
TC Verification
All the above reports shall be verified for compliance to the
following.
• Date of testing and Report date
• Heat number reference
• NDE Reference Number
• Foundry Reference / identification
• Material Grade Identification
• Size, Class rating and Quantity
• Standard / Procedure Reference
• Method / Technique Reference
• Drawing Number Reference
• Area and coverage for NDE
• Report reviewed and approved by Authorized personnel
• Other applicable references as required by specific Material
Standard / Customer requirement.