Ingénierie d'application
La carte matière du BIW
Une caisse en blanc n'est pas faite d'un seul acier. Elle est constituée de différents niveaux de résistance — panneaux de porte, capot, pieds A/B et supports de siège utilisent chacun une matière différente. Voici ce dont chaque pièce est habituellement faite, et la nuance correspondante.
1. Familles de matériaux par niveau de résistance
Douze familles couvrent presque toutes les pièces embouties d'une caisse moderne.
| Famille | Nuances typiques | Limite élastique (MPa) | Traction (MPa) | Allong. A80 (%) | Usage typique |
|---|---|---|---|---|---|
| Mild steel (MS) | CR1–CR5 · DC01–DC06 · SPCC–SPCG | 140–280 | 270–410 | 28–44 | Body panels, floor, inner panels — best formability, lowest cost |
| Interstitial-free (IF) | CR180IF – CR240IF | 180–240 | 320–400 | 31–35 | Deep-drawn outer panels with no ageing |
| Bake-hardening (BH) | CR180BH – CR270BH | 180–270 | 290–460 | 27–34 | Door outer, roof — dent resistance rises after paint bake |
| HSLA | CR340LA – CR550LA · HX260LAD – HX500LAD | 260–550 | 350–690 | 13–26 | Longitudinal rails, cross members, reinforcements |
| Dual phase (DP) | CR290Y490T-DP – CR700Y980T-DP | 290–700 | 490–980 | 10–24 | Crash members, B-pillar, bumper beams |
| Complex phase (CP) | CR570Y780T-CP – CR900Y1180T-CP | 570–900 | 780–1180 | 8–14 | B-pillar, rocker, intrusion beams |
| TRIP | CR400Y690T-TR · CR450Y780T-TR | 400–450 | 690–780 | 20–26 | Complex-formed structural parts with high energy absorption |
| Martensitic (MS) | CR860Y1100T-MS – CR1350Y1700T-MS | 860–1350 | 1100–1700 | 5–8 | Door beams, bumper reinforcement |
| Press-hardened (PHS) | 22MnB5 (hot stamped) | 1000–1200 | 1500–2000 | 5–8 | A/B-pillar, rocker, bumper beam — Al-Si coated |
| Aluminium | 5182 · 6016-T4 · 6082-T6 | 100–280 | 200–350 | 10–25 | Hood, fender, bumper beam, battery housing |
| Magnesium | AZ31 · AZ91 | — | — | — | Instrument-panel beam, steering-wheel armature |
| Composites | SMC · GMT · CFRP | — | — | — | Closures and structural inserts in low-volume programmes |
2. Carte matière pièce par pièce
Regroupées par zone de caisse. Les fenêtres de nuances sont les plages habituellement proposées par les emboutisseurs de rang 1 ; la valeur contractuelle provient toujours de la norme matière du constructeur.
| Zone | Pièce | Fonction | Famille de matériau | Nuances typiques |
|---|---|---|---|---|
| Front structure | ||||
| Front structure | Front bumper beam | Low-speed energy absorption | PHS / DP / Al | 22MnB5 · DP780 · 6082-T6 |
| Front structure | Front crash box | Crush energy absorption | PHS / Al | 22MnB5 · 6082-T6 |
| Front structure | Front longitudinal rail | Frontal crash load path | DP / HSLA | DP590 · DP780 · CR420LA |
| Front structure | Front rail reinforcement | Local reinforcement | PHS | 22MnB5 |
| Front structure | Upper radiator cross member | Front-end frame | HSLA / DP | CR340LA · DP590 |
| Front structure | Lower radiator cross member | Front-end frame | HSLA | CR340LA · CR420LA |
| Front structure | Shock tower | Suspension mounting | DP / Al | DP590 · 6082-T6 |
| Front structure | Front wheel house | Wheel arch enclosure | Mild / HSLA | DC03 · CR340LA |
| Front structure | Dash panel (firewall) | Cabin separation | Mild / HSLA | DC04 · CR340LA |
| Front structure | Dash lower panel | Firewall reinforcement | HSLA | CR340LA · CR420LA |
| Front structure | Front floor | Cabin load bearing | Mild | DC03 · DC04 · DC05 |
| Front structure | Front splash shield | Mud and water shield | Mild | DC03 |
| Centre structure | ||||
| Centre structure | A-pillar outer | Side impact and roof crush | PHS | 22MnB5 |
| Centre structure | A-pillar inner / reinforcement | A-pillar reinforcement | PHS / DP | 22MnB5 · DP780 |
| Centre structure | Roof rail | Upper longitudinal load path | PHS / DP | 22MnB5 · DP780 |
| Centre structure | B-pillar outer | Side-impact core | PHS | 22MnB5 (1500 / 2000 grade) |
| Centre structure | B-pillar inner / reinforcement | B-pillar reinforcement | PHS / CP | 22MnB5 · CR780Y980T-CP |
| Centre structure | C-pillar | Rear structure, rear impact | PHS / DP | 22MnB5 · DP780 |
| Centre structure | Rocker outer (sill) | Side impact, battery protection | PHS / DP | 22MnB5 · DP780 · DP980 |
| Centre structure | Rocker inner / reinforcement | Sill reinforcement | PHS / CP | 22MnB5 · CR780Y980T-CP |
| Centre structure | Floor tunnel | Floor longitudinal reinforcement | DP / HSLA | DP590 · CR420LA |
| Centre structure | Front seat cross member | Seat mounting | HSLA / DP | CR420LA · DP590 |
| Centre structure | Rear seat cross member | Seat mounting | HSLA / DP | CR420LA · DP590 |
| Centre structure | Floor panel | Cabin load bearing | Mild | DC03 · DC04 · DC05 |
| Centre structure | Body side inner | Body structure | Mild / HSLA | DC03 · CR340LA |
| Centre structure | Body side outer | Exterior panel | Mild / IF | DC05 · DC06 · CR210IF |
| Centre structure | Roof panel | Exterior panel | Mild / BH | DC05 · DC06 · CR180BH |
| Centre structure | Roof bow | Roof crush, panel support | HSLA / DP | CR340LA · DP590 |
| Rear structure | ||||
| Rear structure | Rear longitudinal rail | Rear crash load path | DP / HSLA | DP590 · DP780 · CR420LA |
| Rear structure | Rear cross member | Rear structure | HSLA / DP | CR340LA · DP590 |
| Rear structure | Rear wheel house | Wheel arch enclosure | Mild | DC03 · DC04 |
| Rear structure | Rear floor | Luggage compartment | Mild | DC03 · DC04 |
| Rear structure | Rear panel | Rear closure | Mild | DC03 · DC04 |
| Rear structure | Rear bumper beam | Rear impact | PHS / Al | 22MnB5 · 6082-T6 |
| Rear structure | Spare wheel well | Spare wheel bay | Mild | DC03 · DC04 |
| Doors | ||||
| Doors | Door outer panel | Exterior panel | Mild / IF / BH / Al | DC05 · DC06 · CR180BH · 6016-T4 |
| Doors | Door inner panel | Load bearing, attachments | Mild / HSLA | DC04 · CR340LA |
| Doors | Door intrusion beam | Side-impact protection | PHS / DP | 22MnB5 · DP780 |
| Doors | Hinge reinforcement | Hinge mounting | PHS / DP | 22MnB5 · DP590 |
| Doors | Latch reinforcement | Latch mounting | PHS / DP | 22MnB5 · DP590 |
| Doors | Window guide rail | Glass guidance | HSLA | CR340LA |
| Doors | Door frame | Door structure | HSLA / DP | CR340LA · DP590 |
| Hood / tailgate / fender | ||||
| Hood / tailgate / fender | Hood outer | Exterior panel | Mild / Al | DC05 · DC06 · 6016-T4 |
| Hood / tailgate / fender | Hood inner | Structure, pedestrian protection | HSLA / DP | CR340LA · DP590 |
| Hood / tailgate / fender | Hood hinge | Closure connection | HSLA | DP590 |
| Hood / tailgate / fender | Hood latch reinforcement | Latch mounting | HSLA | CR420LA |
| Hood / tailgate / fender | Tailgate outer | Exterior panel | Mild / Al | DC05 · DC06 · 6016-T4 |
| Hood / tailgate / fender | Tailgate inner | Structure, attachments | HSLA / DP | CR340LA · DP590 |
| Hood / tailgate / fender | Tailgate hinge reinforcement | Hinge mounting | PHS / DP | 22MnB5 · DP590 |
| Hood / tailgate / fender | Front fender | Exterior panel | Mild / Al | DC05 · DC06 · 6016-T4 |
| Chassis & EV | ||||
| Chassis & EV | Front subframe | Chassis mounting | HSLA / Al | DP590 · 6082-T6 |
| Chassis & EV | Rear subframe | Chassis mounting | HSLA / Al | DP590 · 6082-T6 |
| Chassis & EV | Tow hook reinforcement | Towing load | PHS | 22MnB5 |
| Chassis & EV | Jack support | Lifting load | HSLA | CR420LA |
| Chassis & EV | Battery pack lower housing (EV) | Battery load and protection | HSLA / Al | DP780 · 6082-T6 |
| Chassis & EV | Battery pack frame (EV) | Battery protection | PHS / Al | 22MnB5 · 6082-T6 |
| Chassis & EV | Dash insulator | NVH | Mild / composite | DC03 · damping laminate |
| Chassis & EV | Wheel house liner | Protection and NVH | Plastic / mild | PP+EPDM · DC03 |
| Chassis & EV | Front bumper carrier | Bumper support | HSLA / plastic | CR340LA · PP+GF |
| Chassis & EV | Rear bumper carrier | Bumper support | HSLA / plastic | CR340LA · PP+GF |
Repères indicatifs fondés sur des normes publiques (VDA 239-100, EN 10346, EN 10130, JIS G3141/G3135, ASTM A653). Les nuances réelles sont fixées par la norme matière du constructeur pour chaque programme — nous chiffrons selon votre spécification, pas selon ce tableau.
Vous ne savez pas quelle nuance convient à votre pièce ?
Envoyez le nom de la pièce, l'épaisseur, le revêtement et le volume annuel. Nous revenons avec la fenêtre de nuances, la source laminoir et un prix — généralement sous un jour ouvré.