The document discusses material specification and designation systems. It describes how materials are classified and designated according to standards like BIS, AISI, and SAE. It then summarizes the designation systems for various material types like cast irons, plain carbon steels, tool steels, low-alloy steels, and high-alloy steels. The designation systems are based on mechanical properties, chemical composition, or both. Key details like material type, percentage of elements, and minimum properties are encoded in the designation codes.

1. DEPARMENT OF DIPLOMA MECHANICAL
ENGINEERING
PRESENTATION ON
Presentation By,
Prof. Mayur S. Itankar
B.E (MECH), M.TECH(HPE)
Session : 2017-18
BALLARPUR INSTITUTE OF TECHNOLOGY,
BALLARPUR

2. DESIGNATION OR IDENTIFICATION OF
MATERIAL CLASS BY A NUMBER, LETTER,
SYMBOL, NAME OR A COMBINATION IS
CALLED SPECIFICATION.
NORALLY BASED ON MECHANICAL
PROPERTIES OR CHEMICAL COMPOSITION.

3. MATERIALS CLASSIFIED AND DESIGNATED
AS PER FOLLOWING STANDARD
BIS- BEAURO OF INDIAN STANDARD
AISI- AMERICAN IRON AND STEEL
INSTITUTE
SAE- SOCIETY OF AUTOMOTIVE
ENGINEERS
BS- BRITISH STANDARDS

4. DESIGNATION OF FOLLOWING MATERIALS
ARE CONSIDERED---( AS PER IS)
CAST IRON
PLAIN C STEELS
TOOL STEELS
LOW AND MEDIUM ALLOY STEELS
(ALLOYING ELEMENTS < 10 % )
HIGH ALOY STEELS
(ALLOYING ELEMENTS < 10 % )

5. DESIGNATION OF CAST IRONS
FIRST SYMBOL FOR TYPE OF CAST IRON
NUMBER – INDICATES MINIMUM TENSILE STRENGTH
SYMBOLS AS
FG – GRAY CI
WM – WHITE HEART MALLEABLE CI
PM – PEARLITIC MALLEABLE CI
SG – SPHEROIDAL GRAPHITE CI
e.g.
FG150
GRAY CI TS 150 N/SQ.MM
IT IS GRAY CAST IRON WITH MIN. TS 150 N/SQ.MM OR MPa

6. WM250- WHITE HEART MALLEABLE CI WITH
MIN. TS=250 N/SQ.MM
SG150- SPHEROIDAL GRAPHITE WITH MIN.
TS=150 N/SQ.MM
 DESIGNATION ON THE BASIS OF
MECHANICAL PROPERTIES…
DESIGNATED BY TENSILE OR YIELD STRENGTH
Fe- INDICATES STEEL
E – INDICATES YIELD STRENGTH
K- KILLED STEEL

7. IF E IS NOT SHOWN THEN TS IS CONSIDERED.
e.g.
Fe 350 – STEEL WITH MIN. TS 350 N/SQ.MM
Fe E 380 – STEEL WITH MIN. YIELD STRENGTH
380 N/SQ.MM
E- FOR YIELD STRENGTH
Fe 410 K – KILLED STEEL WITH MIN TS 410 N/SQ.MM
K- KILLED AND Fe FOR STEEL i.e. KILLED STEEL
KILLED STEEL IS DEOXYDIZED FULLY SO THAT
CASTING ARE SOUND AND FREE FROM BLOW HOLES.

8. DESIGNATION AS PER CHEMICAL COMPOSITION:
PLAIN C STEELS:
e.g.
40C8
0.4 % CARBON AND 0.8 % Mn
NUMBER AFTER C IS PERCENT OF Mn
FOR Mn MULTIPLYING FACTOR IS 10 i.e.
10/100=1/10
SO 8/10=0.8 %
NUMBER BEFORE C SHOWS % CARBON
40/100=0.4%

9. 45 C 10 S 18
0.45 % C, 1.0 % Mn, 0.18 % S
PLAIN C STEELS HAVE C, P, S, Mn, Si AS INGREDIENTS
Except Mn all elements are considered 100%
i.e. divide by 100, as 18/100 = 0.18 %
DESIGNATION OF TOOL STEELS:
10 T 4
TOOL STEEL CONTAINING 0.1 % C , 0.4 % Mn
T- INDICATES TOOL STEEL

10. DESIGNATION OF LOW AND MEDIUM ALLOY STEELS:
FIRST NUMBER --- INDICATES % CARBON
SECOND, FOURTH, SIXTH – INDICATES ALLOYING
ELEMENTS
THIRD, FIFTH, SEVENTH – INDICATES MULTIPLYING
FACTOR/100
ALLOYING ELEMENTS MULTIPLYI
NG FACTOR
Cr, Co, Ni, Mn, Si, W 4
Al, Pb, Cu, Be, V, Nb, Ti, Mo 10
P, S, N 100

11. 40 Cr 4 Mo 3
LOW ALLOY STEEL 0.4 % C , 1 % Cr, 0.3 % Mo
DIVIDE BY MULTIPLYING FACTOR
i.e. 4/4=1 % FOR Cr,
AND 3/10=0.3 % FOR Mo
ALLOYING ELEMENTS MULTIPLYING
FACTOR
Cr, Co, Ni, Mn, Si, W 4
Al, Pb, Cu, Be, V, Nb, Ti, Mo 10
P, S, N 100
35 Mn 6 Mo 3
ALLOY STEEL WITH 0.35 % C, 1.5 % Mn, 0.3 %Mo

12. DESIGNATION OF
ALLOY STEEL & HIGH ALLOY TOOL STEEL
X- INDICATES HIGH ALLOY STEEL
XT – INDICATES HIGH ALLOY TOOL STEEL
MULTIPLYING FACTOR NOT USED
FOR ALLOYING ELEMENTS NUMBER GIVES % OF
ELEMENTS
e.g. X 15 Cr 25 Ni 12
HIGH ALLOY STEEL 0.15 % C, 25 % Cr, 12 % Ni
XT 75 W 18 Cr 4 V 1
HIGH ALLOY TOOL STEEEL 0.75 % C , 18 % W, 4 % Cr, 1 % V

13. STATE THE MEANING OF THE FOLLOWING …
T 70 TOOL STEEL HAVING 0.7 % C
Fe 470 W STEEL WITH MIN TS 470 N/SQ.MM
AND HAVING GOOD WELDABILITY
45 C 10 S 18 STEEL WITH 0.45 % C, 1.0 % Mn,
0.18 % S
XT 60 W 12 Cr 4 V 1 HIGH ALLOY TOOL STEEL WITH
0.6 % C, 12 % W, 4 % Cr, 1 % V

14. AISI- AMERICAN IRON STEEL INSTITUTION
DESIGNATION
• 35C8 i.e. 0.35 %CARBON, 0.8 % Mn.
• AISI1035 i.e. plain carbon steel containing 0.35 %
carbon. (Digit 1 indicates plain c steel.)
• AISI5140, AISI4140,AISI6150,AISI8640.
1st digit indicates type of steel.
2nd digit for predominant alloying element.
3rd &4th digit indicates% of carbon in hundredth.
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15. e.g. 1 for plain carbon steel,
2 nickel series,
3 for nickel chromium,
31 for manganese steel.
4 for chromium steel.
41 for chromium-molybdenum steels,
51 for medium chromium,
61 Chromium-vanadium series.
92XX FOR SILICON SERIES.
AISI5140 i.e. medium cr steel with 0.40%c.
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16. THANKS !!!