MATERIALS
STEEL SHEETS AND STRIPS STANDARD
MICROALLOYED, HOT ROLLED, 52812
 CLOSE TEMPERATURE CONTROL,  
HIGH YIELD STRENGTH    
   

     
Supervisor :
Supervisor: FEDERICI Claudio D.I.P.
D.I.P. – Central Laboratories
Laboratories Tel. 011.6835758
011.6835758      
     

Manager :
Manager: BOTTAZZI Mauro D.I.P. – Central Laboratories Tel. 011.6833070
011.6833070   
   
  
   

SCOPE    
   
To define the characteristics for microalloyed low carbon, close temperature control hot rolled,
 
high yield strengt h steel sheets and strips, for medium and light drawing and cold bending    
  
   

     

Reference GM
  
  
   
GMW3032 M – ST – S    
   
   
High Strength Sheet Steel (180 MPa – 550 MPa Yield Strengths)    

This Standard consist s of 10 pages

  

 –– Oct. 84 3rd Edition – Fully revised . (AS)

 –– Jan. 02 4th Edition – Completely revised to comply to GM Standard

GMW3032 M–ST–S. (AD
AD))

   
   
       
       
       
       
       
   
       
   
       
   
          
           
           
   
          
          
       
      
         
           
     
       
         
   
           
   
          
           
   
      
           
   
               
              
       
           
              
          
           
               
              
           
       
          
          
             
              
          
   
       
       
           
           
          
   
          
         
           
       
       
           
          
          
          
       
       
   
   
   
       
                      
   

    

  
52812 

| § ‘‘A’’ : TEST EQUIPMENT

The equipment required for the tests is indicated in the Standards listed in para. “B”.

| § ‘‘B’’ REFERENCES

|50020 | Material data processing coding TMD

|50108 | General test – Rockwell hardness test. TMD

|50113 | Tension testing – general purpose tests. TMD

|50116 | Tests on metals – Determination of formability indices. TMD

|50125 | General test – Bend test. TMD

|50240 | Requirements for ferrous metals – Pipes, sheets, wide strips, flat strips and
sections – Test procedures and preparat ion of specimens. TMD

|52120 | Chemical composition variations on steel products. TMD

|54406 | Hot rolled steel sheet and strips – Dimensions and tolerances. F2

|9.01102 | Quality of FIAT AUTO S.p.A. supplies CFO

   
   
       
       
       
        |9.50240 | Steel sheets and strips – Technical supply requirements. CMD
       
   
       
   
           
          
           
   
           |3244–UNI | Microscopic inspection of ferrous materials – Assessment of non metallic
          
           inclusions in steels by means of standard images.
       
   
         
   
           
     
       
         
           
   
          
       
|3245–UNI | Microscopic examination of ferrous materials. Determination of the size of
       
   
           
       austenit ic or ferritic grain in the steel.
              
   
              
           
       
               
           
           | 000–EN.78.0 | Authorizat ion to use products that vary from the technical specificat ions. (D.P:
              
              
           
        Dept – Industrial Methodo logy Development)
           
          
             
               
           
   
      
       
           
           
          
          
   
         
       
       
          
           
          
          
          
         
       
   
       
   
   
   

    

  

52812

GENERAL

1.1

Material

Low carbon steel sheet with a thickness betwee n 1 and 16 mm, microalloyed, anti–ag ing, not for
heat treat ment , suppl ied as close tempera tur e contr ol hot–r olled in sheet s or coils for medium and
light drawing and cold bending applications in order to avoid altering mechani cal properties.

1.2

Application

Highly stressed structural parts.

EXAMPLE OF INDICATION ON DRAWING, N OF DATA PROCESSING CODE

AND CORRESPONDING FIAT AND G.M. CODES.



Example of indication on drawing and number of data processing code

MAJOR
Steel sheets and strips not to be used in NEW DESIGNS started after 01/01/2002.

INDICATION ON DRAWING Code Number    

       
   
Data processing        
       
        
(As per Standard 50020)        
   
       
   
           
          
           
          
   
FE E 275 20165           
          
           
           
     
       
     
       
         
FE E 355 20153            
   
   
          
           
   
           
      
              
   
              
FE E 420 20112            
       
               
           
          
              
              
FE E 490 20154            
       
           
          
             
              
   
           
          
 This identifica tion of the semi–finished product is to be completed with the    
           
   
          
   
associated symbol regarding appearance and surface finish as per    
          
   
         
Procurement Specification 9.50240.       
       
          
The general supply conditions are indicated in Procurement Specification            
          
9.50240.           
          
         
       
   
   
       
   
   

    

  
52812 



Example of indication on drawing, n of data processing code and correspondence to

GMW

MAJOR
Steel sheets and strips to be used in NEW DESIGNS started after 01/01/2002.

Code Number
INDI CATION ON DRAWING CORRISPONDENCE TO
Data processing
 GM W
(As per Standard 50020)

FEE 270 20186 GMW 3032 M – ST – S HR 270

FEE 300 20187 GMW 3032 M – ST – S HR 300

FEE 340 20188 GMW 3032 M – ST – S HR 340

FEE 380 20189 GMW 3032 M – ST – S HR 380

FEE 420 20190 GMW 3032 M – ST – S HR 420

   
   
       
       
FEE 500 20191 GMW 3032 M – ST – S HR 500
       
       
       
   
       
   
           
          
             This identification of the semi – f inished product is to be completed with the
   
          
          
          
associate d symbol regarding appearance and surface finish as per Procurem ent
       
   
         
    Specification 9.50240.
           
     
       
          The general suppl y condit ions are indicat ed in Procur eme nt Speci fic atio n9.50240.
           
   
          
   
           
   
           
      
              
   
              
           
       
               
           
          
              
              
           
3
       
           
          
             
                CLASSIFICATION AND CHARACTERISTICS TO BE CHECKED
           
   
      
       
           
            3.1
          
          
   
         
       
       
           General applications
           
          
          
           Unless otherwise specified when ordering, the tables indicated in items 5 and 6 are to be compli ed
         
       
   
       
   
    to .
   

    

  

52812



Designs started before 01/01/2002

CHARACTERIS TICS TO BE CHECKED (X)

APPLICATIONS Tension
MATERIAL
 (GENERAL) Chemic al com- hardness
St ru ct ur e R es il ie nce
position and ben-
ding

FE E 275 Parts with deep drawings (X) (X) (X) (X)

Parts with medium bending

FE E 355 (X) (X) (X) (X)
and drawing

Very stressed parts with

FE E 420 medium and light bending (X) (X) (X) (X)
and drawing

Very stresse d part s with light

FE E 490 (X) (X) (X) (X)
bending and drawing



New designs started after 01/01/2002

CHARACTERIS TICS TO BE CHECKED (X)

MATERIAL APPLICATIONS
Tension    
 ( GENERAL) Chemical com- Formabi-        
   
and ben- Structure        
       
position lity index        
ding        
   
       
   
           
          
           
Parts with difficult bending           
   
FEE 270 (X) (X) (X) (X)           
and drawing           
           
           
     
       
     
       
Parts with medium a nd diffi-          
FEE 300 (X) (X) (X) (X)            
   
   
          
cult bending and drawing            
   
           
      
              
   
              
Parts with medium bending            
       
FEE 340 (X) (X) (X) (X)                
and drawing            
          
              
              
           
       
Very stressed parts with            
          
             
FEE 380 medium and light bending (X) (X) (X) (X)               
   
           
and drawing       
       
           
   
          
       
          
   
         
Very stresse d part s with light       
       
FEE 420 (X) (X) (X) (X)           
bending and drawing            
          
          
          
         
Very stresse d part s with ben-        
   
FEE 500 (X) (X) (X) (X)    
       
ding and forming    
   

    

  
52812 

3.2

Special applications

For very demanding applications and only for exceptional cases, the order is to have attached the
“Rolled product data sheet” appropriately prepared by the “Product Definition Services”. An
example of this form is illustrat ed in Procurem ent Specification 9.50240.

The material identific ation is to be slightly changed with the addition of “KP” in high case
preceded by a dash.

Example: For old designs: FE E 355 F – KP.

For new designs: FEE 340 F – KP.

3.3
Variances

If material is used that has character istics different to those indicated below, the Variance
Authoriz ation Request Procedure 000–EN.78.0 and Procurement Specification 9.01102 are to be
applied.

SURFACE APPEARANCE

4.1
Appearance and finish
   
   
        For definition of appearanc e ratings MH, MG or MF see procurement Specificat ion 9.50240.
       
       
       
       
   
       
   
           
          
           
   
           
          
          
       
   
         
    Visual inspection
           
     
       
         
           
   
The rolled product s are to be free of defects tha t could adversely affect norm al use.
          
   
           
   
           
       The surface s are to be technically clean , free of rust and foreign matter. Flaws that could cause
              
   
              
           
        failures duri ng service, damage to equipment, welding or brazing problems or paint or protect ive
               
           
           coating adhesion difficult ies are not allowed.
              
              
           
        According to the spec ificatio ns of the order, the rolled sheets may be supplied with as–rolled or
           
          
              trimm ed edges. Edge condition shall not jeopardize semi finished product applicatio n.
               
           
   
      
       
           
           
          
          
   
         
       
       
          
           
          
          
          
         
       
   
       
   
   
   

    

  

52812


% LADLE ANALYSIS
Rare earth elements may be added (TR) to reduce the transverse effect.
Maximum allowed variatio ns are indicated in Standard 52120.



Design s started before 01/01/2 002

Nb
C Mn Si P S Al min.
MATERIAL
Max. Max. Max. Max. Max. min.


FE E 275 0.015
0.10 0.60
FE E 355 0.020
0.40 0.025 0.025 0.020
FE E 420 0.11 1.00 0.030

FE E 490 0.12 1.60 0.040

 No other microalloy elements are allowed, unless otherwise agreed upon when ordering.



New designs started after 01/01/2002

   
C Mn P S Al Si        
   
MATERIAL        
       
Max. Max. Max. Max. min. Max.        
       
   
       
   
           
          
           
FE E 270 1.00           
   
          
          
           
           
     
       
     
       
         
FE E 300 1.30            
   
   
          
           
   
           
      
              
   
              
FE E 340 1.50            
       
               
           
          
0.12 0.030 0.030 0.015 0.50               
              
           
       
FE E 380 1.50            
          
             
              
   
           
      
       
           
   
FE E 420 1.60           
       
          
   
         
      
       
          
           
FE E 500 1.70           
          
          
         
       
   
   
       
   
Microalloy elements: Nb 0.015 to 0.040    

Nb + Ti + V  0. 2

    

  
           
           
        

   
CHARACTERISTICS:  
  
  
Mechanical properties (Designs started before 01/01/2002)  

Tension test (Standard 50113)  Resilience test on

specimen
Hardness t est Test f or    
longitudinal in    
(Rockwell) bending Index of     
Min elongation % direction of   
  
formability rolling  
Load Load at o spper tan-- spper tan--
unit
  
unit of yield – break dard 50108) dard 50125) (As per Stan-
Designation yield Specimen (As per Standard
of Failure longitudinal in dard 50116) 50130)
 
Rs
R   
  
 
 
  
semi–fini- min. direction of
shed product rolling
  


 
 
 
 
  
 
 
  
A80 (A) Work harde- KV min.
s<3 s  3 J
 
D/a ning
N/mm 2 N/mm2

Rs/R max.. HRB max..
 = 180 


 
 

mm mm n min. t – 20  C

 
 
  
 

 
FE E 275 350  470 275 0,89 23 29 82 0 0,17 40

FE E 355 415  530 355 0,89 21 26 87 0 0,16 40

FE E 420 470  590 420 0,89 19 24 91 0,5 –– 40

FE E 490 540  690 490 0,89 15 20 95 1,0 –– 40

 For test specimen cutting see Standard 50240. For reject purposes valid rated values are R, Rs, A %, r and n obtained as average of 3 determinations.

 Test not decisive for rejectio n purposes. Results of tensile test and st ructural inspection shall prevai l in disputed cases.

 Only when requested and for thicknesses to be agreed upon, and in any case  5 mm.

 

52812


Mechanical properties (New designs started after 01/01/2002)

Tension test (Standard 50113) 

Index of
(longitudinal direction)
formability
(As p
per Standard Test for
50116) bending
(As per Stan-
Load Load dard 50125
unit unit
Design ation of    
Failure yield       
semi–finished
R Rs      
product Minimum
     
elongation       
  
   
     
  
       
A80 %       
  
      
    D/ a
mm2 mm 2
α = 180 
r min. n min.

FEE 270 330 270 350 27 0.15 0

FEE 300 370 300 380 25 0.14 0

  

52812


Mechanical properties (New designs started after 01/01/2002)

Tension test (Standard 50113) 

Index of
(longitudinal direction)
formability
(As p
per Standard Test for
50116) bending
(As per Stan-
Load Load dard 50125
unit unit
Design ation of    
Failure yield       
semi–finished
R Rs      
product Minimum
     
elongation       
  
   
     
  
       
A80 %       
  
      
    D/ a
mm2 mm 2
α = 180 
r min. n min.

FEE 270 330 270 350 27 0.15 0

FEE 300 370 300 380 25 0.14 0

FEE 340 410 340 420 23 0.13 0.5

n er
study
FEE 380 450 380 460 21 0.12 0.5

   
       
   
FEE 420 480 420 520 20 0.11  1. 0        
       
       
       
   
       
   
           
          
FEE 500 560 500 600 18 0.09  1. 5            
          
   
          
          
           
           
     
       
     
 For test specim en cutting see Standard 50240. For reject purpos es valid rated values are R, Rs,        
         
           
   
A %, r and n obtained as average of 3 determ inations.    
          
           
   
           
      
              
   
              
 Evaluated by 6 % at the end of even elongat ion.            
       
               
           
          
              
 Test not decisive for rejection purposes. Results of tensile test and structu ral inspection shall               
           
       
prevail in disputed cases.            
          
             
              
   
           
      
       
           
   
          
       
          
   
         
      
       
           
           
          
          
Weldability           
         
       
   
   
Weldability is guaranteed for normal processes and normal welding applications.        
   
   
Special procedur es and applications are to be agreed upon at the time of ordering.
The zone affected by casting heat undergoe s a certain reduction in mechanical strengt h but no
embrittlement.

    

  
52812 


Structure
Struct ure shall be ferritic with evenly distributed fine grains. The grains shall not have preferent ial
orie ntat ion. The size of the grains , determi ned as per Stand ard UNI 3245, is to be 10 or fine r. Size
9 grains are allowed only in percenta ges less than 10 %.

Type A inclusions are not to exceed grade 3 of the JK scale (UNI 3244).

The struct ure inspection is to be made at 1/3 of the rolled product width.


Dimensions and tolerances
See Standard 54406.

   
   
       
       
       
       
       
   
       
   
           
          
           
   
          
          
          
       
   
         
   
           
     
       
         
           
   
          
   
           
   
           
      
              
   
              
           
       
               
           
          
              
              
           
       
           
          
             
               
           
   
      
       
           
           
          
          
   
         
       
       
          
           
          
          
          
         
       
   
       
   
   
   

    