BMW 5 Series: Body overview, Body structure

Body overview

G30 Side frame structure

1. Multiphase steel (> 300 N/mm²)
2. Ultra-high-strength steel (> 900 N/mm²)
3. Aluminum
4. Deep-drawing steel (< 300 N/mm²)
5. Other steel grades

1. Inner roof frame
2. Roof frame reinforcement
3. B-pillar reinforcement
4. Side sill reinforcement plate
5. Outer side frame (deep-drawing steel)

Body structure

The lightweight body construction concept of the G30 comprises high-strength steel and Aluminum components. There is no Carbon Core used in the construction of the G30 body like in the G12. The use of die-cast Aluminum components has increased significantly. Thanks to the material mix, the materials are able to contribute their specific strengths to the vehicle in the best possible way. As a result of the strict lightweight construction philosophy, the weight of the body has been reduced by around 46 kg / 101 lbs over the predecessor F10, but crash safety has been further improved.

Steel

G30 Ultra-high-strength steels in the body structure

1. Carrier support, bulkhead
2. Inner side frame
3. Engine support extension
4. Reinforcement plate, B-pillar
5. Side sill reinforcement plate
6. Outer connecting plate

Aluminum

The use of Aluminum extruded profiles and complex die-cast Aluminum parts accounts for a rigid body along with low weight. All requirements relating to passive safety are also met.

The spring strut domes on the front, and for the first time also on the rear, are manufactured using the Aluminum pressure die casting process. As is already familiar from the G12, the side members at the rear are now also made as die-cast Aluminum components. This contributes to excellent weight distribution in the body structure. New Aluminum cast alloys were also developed in order to increase the crash safety of these components.

G30 Aluminum in the body structure

1. Front spring strut dome
2. Rear spring strut dome
3. Side member
4. Engine support

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