aceros en automocion
TRANSCRIPT
Potential for Mn in New Automotive Steels
Hot Rolled Products Overview and Evolution
Elongation(%)
40
35
30
25
20
15
10
400 500 600 700 800 900 1000
USIPHASE D550USIPHASE D 600
USIFORM 450-550
USIDUR315-420
USIPHASE D800
USIFORM 600
Trend
USIPHASE T 800
Increase Strength-Ductility Balance Availability of very HSS in low thicknesses
Precoated Products
1100 T.S. Mpa
USIPHASE M 1000 (t 1.6 mm)
TrendUSIPHASE M 800 (t 1.6 mm)
USIDUR 700
Trend to low thicknesses
TS (
MP
a)
El ( %)20 30 4010 50
300
400
500
600
700
800
TRIPDual PhaseDual Phase HSSMicroalloyed (HSLA)HS IsotropicBake-Hardening (HS BH)IF HSRephosphorized USISTAMP06USISTAMP07
Colled rolled steels1000
900
Floor Panel in EDDQ Steel
Seat Stand
USIPHASE D 600Ferrite + Martensite
20 µm
Dual Phase Microstructure
USIPHASE T 800Ferrite + Bainite + Residual Austenite
TRIP Microstructure
20 µm
Arcelor Offer: Ts 600MPa
10
15
20
25
30
35
0 1 2 3 4 5Available thicknesses (mm)
Tota
l elo
ngat
ion
B/ HDG(<4mm)Usiform 600
Usiphase D60
B/ EZ(<3mm)
Usiphase D600
B/HDG/EZ
Arcelor Offer: Ts 800MPa
10
15
20
25
30
35
0 1 2 3 4 5Available thicknesses (mm)
Tota
l elo
ngat
ion
B/ EZ(<3mm) /HDG(<3mm)
Usiphase M800
Usiphase D80
B/ EZ(<3mm)
Usiphase D750
B/HDG/ EZ(<2mm)
Usiphase T800
B/EZ
Usiphase T800
B/EZ
Arcelor Offer: Ts 1000MPa
Available thicknesses (mm)
5
10
15
20
25
30
0 1 2 3 4 5
B/ EZ
Usiphase T1000
B/ HDG
Usiphase D1000B(<2mm) /HDG
Usiphase M1000Tota
l elo
ngat
ion
Chassis Parts
Dimensioning Stresses Processing Constraints
StiffnessE
Crash(YS, TS,El%, n)
Fatigue(TS)
ExceptionalStresses(YS, E)
Profilage Welding Stamping Stretchflanging
Wheel Rims
Wheel disks
Suspension arms
Engine cradles
Rear Axle
* * * * * * *
*
*
*
*
*
*
*
*
*
*
* * *
* * *
* * *
* * *
* * *
* * * * * *
* * *
* * *
Nakazima-Hecker Method
Hole Expansion Ratio'(AC%=(D-Do)/Do x100))
T.S. (MPa)
400 500 600 700 800 900 1000
180
160
140
120
100
80
USIDUR315-550
USIFORM 450-550
DP55 - 60
USIFORM 600
USIFORM 800
Die
Punch
Load 400N(rubber punch
diameter 15 mmhardness =80 shore)
1
2 3
4
0,60
0,80
1,00
1,20
1,40
1,60
1,80
2,00
POINT 1 POINT 2 POINT 3 POINT 4
Rem
aine
d de
form
atio
n (m
m)
USIPLUS180 0,67 mm
USIPHOR220 0,68 mm
USISTAMP04 0,78 mm
DENT RESISTANCE
INTEREST OFBAKE-HARDENING
STEEL GRADESUSIPLUS
Bake HardeningBake Hardening : 170: 170°°C / 20mnC / 20mn
-- No No ageing and low ageing and low BH BH withoutwithout predeformationpredeformation-- HighHigh BH BH afterafter predeformation predeformation
BH and Ageing Behaviour of DP and TRIP Steels
BH and Ageing Behaviour of DP and TRIP Steels
AgingAging : 70: 70°°C / 10HC / 10H
020406080
100
0 2 4 6 8 10% predeformation
BH after Tensile TestAgeing after T.T.BH after SkPAgeing après SkP
020406080
100
0 2 4 6 8 10 12 14Predeformation (%)
DP450DP500DP600DP750TRIP800
MPaMPa MPaMPa
Crash Energy Management
Anti Intrusion
Energy Absorption
Weight reduction potential in flexion vs. USISTAMP 04 (%)
0%10% 9%
20% 19%23% 24%
32% 34%
58%
33%37%
49% 47%
0,00%
10,00%
20,00%
30,00%
40,00%
50,00%
60,00%
Usistam
p04Usip
hor280
Usidraw
440
Usidur31
5Usip
haseD
450
Usiphas
eD50
0Usip
haseD
600
HLE500
Usiphas
eT80
0Usib
or 1500
Usiphas
eD75
0
Usiphas
eM80
0
Usiphas
eM10
00
Usiphas
eTR10
00
Ultimate force
Lightening potential in axial compression with respect to Usistamp04 (%)
32,430,8
15,1
28,7
31,2
27,928,8
21,0
24,4
19,8
16,0 15,3
10,4
8,09,4
7,1
0,00,0
5,0
10,0
15,0
20,0
25,0
30,0
35,0
Usipha
seTR10
00Usip
hase
D800
HM12HM12
stam
pUsip
hase
M1000
Usipha
seM80
0
Usipha
seTR80
0stam
pUsip
hase
TR800
Usipha
seD75
0HLE
500
Usipha
seD60
0Usip
hase
D500
Usipha
seD45
0Usid
raw44
0Usid
ur315
Usipho
r280
Usistam
p04
DP and TRIP typical mechanical properties
DP and TRIP typical mechanical properties
0100200300400500600700800900
0 5 10 15 20 25 30 35 40Elongation %
Con
vent
iona
l Str
ess
(MPa
)
Dir. Yp0,2 El(%) Ag(%) rd r delta r nd nT 519 840 26,3 21,0 1,18 1,01 0,07 0,217 0,221L 478 830 28,3 22,5 0,90 0,228D 508 834 25,5 21,1 0,97 0,221
0100200300400500600700800900
10001100
0 0,05 0,1 0,15 0,2 0,25Rational Strain
Rat
iona
l Str
ess
(MPa
)
TRIP800TRIP800
Usiphor280Usiphor280
DP600DP600DP750DP750
Usistamp Usistamp 0404
Usidur360Usidur360
TRIP800TRIP800
DP600DP600DP750DP750
Usistamp Usistamp 0404
Usidur360Usidur360
TS
Influence of 10% prestrain on Usiphase D600 GA Fatigue Resistance
Alternating Tension Rs = 0,1
Mechanical CharacteristicsYS = 379 MPa ; TS = 630 MPat = 1,95 mm
Fatigue Results
State σd 5.106 cyclesDelivery 455 MPaPrestrain 10% 541 MPa 300
350
400
450
500
550
600
100000 1000000 10000000
Number of cycles
10% Prestrain
As delivered
Max Stress (Mpa)
0
1
2
3
4
5
6
7
300 400 500 600 700 800
TS (MPa)
Sprin
gbac
kA
ngle
°Problems to considerProblems to consider
SpringbackSpringback ControlControl OthersOthers-- avoid wrinklesavoid wrinklesformation formation then difficuthen difficuto to eliminateeliminate-- Stamping Stamping Presses Presses Capacity Capacity -- tools coatingstools coatings-- toolstools pollution by pollution by steel coatingssteel coatingsdue to due to heatheat-- welding adjustmentswelding adjustments
Decrease with- die radius- punch-die clearance- blankholder force increase
--j/j/epep.=1.2 .=1.2 -- R 3R 3-- R 2R 2
--j/j/epep.=1 .=1 -- R 3R 3-- R 2R 2
--j/j/epep.=0.95 .=0.95 -- R 3R 3-- R 2R 2
UTS (MPa)
A ( %)10 20 30 40 50
300
400
500
600
700
800
1000
900
60 70 80
UTS (MPa)
A ( %)10 20 30 40 5020 30 40 50
300
400
500
600
700
800
1000
900
60 70 8060 70 80
VHS FeMn steels
very ductile FeMn
Development(product & process)
Explorationof metallurgies
FeMn (targets)TRIPDual phaseHSLAIFHSBHRephosphorisedMild
Cold rolled grades
UTS (MPa)
A ( %)10 20 30 40 50
300
400
500
600
700
800
1000
900
60 70 80
UTS (MPa)
A ( %)10 20 30 40 5020 30 40 50
300
400
500
600
700
800
1000
900
60 70 8060 70 80
VHS FeMn steels
very ductile FeMn
Development(product & process)
Explorationof metallurgies
FeMn (targets)TRIPDual phaseHSLAIFHSBHRephosphorisedMild
FeMn (targets)TRIPDual phaseHSLAIFHSBHRephosphorisedMild
Cold rolled grades
Arcelor FeMn – TWIP programme target & status
UTS (MPa)
A ( %)10 20 30 40 50
300
400
500
600
700
800
1000
900
60 70 80
UTS (MPa)
A ( %)10 20 30 40 5020 30 40 50
300
400
500
600
700
800
1000
900
60 70 8060 70 80
VHS FeMn steels
very ductile FeMn
Development(product & process)
Explorationof metallurgies
FeMn (targets)TRIPDual phaseHSLAIFHSBHRephosphorisedMild
Cold rolled grades
UTS (MPa)
A ( %)10 20 30 40 50
300
400
500
600
700
800
1000
900
60 70 80
UTS (MPa)
A ( %)10 20 30 40 5020 30 40 50
300
400
500
600
700
800
1000
900
60 70 8060 70 80
VHS FeMn steels
very ductile FeMn
Development(product & process)
Explorationof metallurgies
FeMn (targets)TRIPDual phaseHSLAIFHSBHRephosphorisedMild
FeMn (targets)TRIPDual phaseHSLAIFHSBHRephosphorisedMild
Cold rolled grades
Arcelor FeMn – TWIP programme target & status
First stage : heating in furnaceFirst stage : heating in furnace
HeatingHeating55--10 min10 min
880880--950 950 °°CCAustenitisationAustenitisation
alloying reaction alloying reaction on coatingon coating
TYPICAL HOT-STAMPING (« direct process»)
Hot stamping : what is it ?
Second stage : hot forming Second stage : hot forming (600(600--800800°°C)C) and ...and ...
HeatingHeating55--10 min10 min
880880--950 950 °°CCAustenitisationAustenitisation
alloying reaction alloying reaction on coatingon coating
Tools : 20°C < T <200°C
First stage : heating in furnaceFirst stage : heating in furnace
TYPICAL HOT-STAMPING (« direct process»)
Hot stamping : what is it ?
ThirdThird stage : quenchingstage : quenching between the between the diesdies
Tools : 20°C < T <200°C
First stage : heating in furnaceFirst stage : heating in furnaceSecond stage : hot forming and ...Second stage : hot forming and ...
TYPICAL HOT-STAMPING (« direct process»)
HOT STAMPING (« direct process »)Fast transfer time between furnace and diesFast transfer time between furnace and dies
Stamping with high speed and low pressureStamping with high speed and low pressuress (200 to 500 (200 to 500 T)T)
Stamping is carried Stamping is carried out out between between 800800°°C C and and 600600°°CC
0
100
200
300
400
500
600
700
0.00 0.10 0.20 0.30 0.40 0.50 0.60
Ger
çek
Ger
ilme
(MPa
)
At high temperature, USIBOR 1500 P has
very high elongations (> 50%)
20°C
400°C
600°C
800°C
Destacking before ovenentrance
Temperature ~ 900°C,Austenitization of blanks
Rapid transfer from ovento the die set
Simultaneous formingand quenchingDies are water cooledPart temperature afterforming: ~ 80°C
TYPICAL HOT-STAMPING LINE (« direct process »)
Bumper Bumper beambeam
Side rail memberSide rail member
BB--pillar reinforcementpillar reinforcement
Door beamsDoor beams
Hood reinforcementHood reinforcementAA--pillar reinforcementpillar reinforcement
USIBOR 1500 P APPLICATIONS
Renault Laguna II
FRONT BUMPER BEAM OF THE LAGUNA IIFRONT BUMPER BEAM OF THE LAGUNA IIUSIBOR 1500 PRECOATED IN 2 mm THICKNESSUSIBOR 1500 PRECOATED IN 2 mm THICKNESS
(PHOTO WITH THE KIND PERMISSION OF RENAULT SA)(PHOTO WITH THE KIND PERMISSION OF RENAULT SA)
USIBOR 1500 P
Citroën C5
SOFEDIT SOFEDIT PicturesPictures
Hot blank justHot blank justbefore stampingbefore stamping
Stamped blankStamped blankbefore cuttingbefore cutting
A PILLAR RENFORCEMENT OF THE CITROA PILLAR RENFORCEMENT OF THE CITROËËN C5N C5USIBOR 1500 PRECOATED IN 1.17 mm THICKNESSUSIBOR 1500 PRECOATED IN 1.17 mm THICKNESS
(PHOTO WITH THE KIND PERMISSION OF PSA PEUGEOT CITRO(PHOTO WITH THE KIND PERMISSION OF PSA PEUGEOT CITROËËN)N)
USIBOR 1500 P
WELDED BLANKS MARKET IN EUROPE
020406080
100120140160
Millions blanks
1997 1999 2001 2003 2005 2007
EUROPE
EUROPE
Multi Thickness Blanks
MTB are Steel Solutions which allow :
• Weight Saving• Reduction of the number of parts• Reduction of the manufacturing time for the function• Reduction of functionnal cost on the Global chain
And / Or an increase of in-service performance.
TYPICAL INDUSTRIAL APPLICATIONS
–Closure inners(hinges and latch reinforcements)–Shock tower–Reinforcements of pillars, – side rails, – front and rear rails and transverse members–Local reinforcements of floor panel–...
CASE OF A DOOR INNER
Door Inner2,3 Kg of weight reduction
•Suppresssion of the post-assembly hinges
•Reinforcement integrated
•Better stiffness
•Cost reduction
•Weight reduction
Laser Tailored Blank
Patchwork
TWB contribute to mass of vehicle reduction
Body side : 8 kg of weight saving (25%)
B. Pillar2.5 kg of Weight Saving
(14%)Suspension support:
1,2 Kg of weight saving (33%)
Rail2,4 Kg of weight saving (18,5%)
Door Inner2,3 Kg of weight saving (17%)