Why We Trust 10.9-Grade Pre-Assembled Screws for High-End EV Chassis

An electric vehicle chassis carries battery weight, torque loads and vibration that traditional ICE vehicles never experience. For engineers, every fastener becomes a safety-critical component - which is why 10.9-grade pre-assembled screws are increasingly the standard choice.

What does 10.9 grade mean?

The grade number describes mechanical properties: 10 refers to a nominal tensile strength of 1000 MPa, and .9 means the yield strength is 90% of that - roughly 900 MPa. In practical terms, a 10.9-grade screw withstands dramatically higher clamping force before permanent deformation.

Why EV chassis need high-strength fasteners

• Battery pack loads - heavy battery modules demand high clamping forces that stay stable over time
• Vibration resistance - high preload prevents loosening under road vibration
• Crash safety - joints must hold deformation energy without shear failure
• Lightweight design - smaller fasteners can be used when material strength is higher

The role of pre-assembled design

Pairing 10.9-grade material with a pre-fitted washer guarantees even load distribution and simplifies automated assembly on the line. For EV manufacturers, this combination improves both safety and production efficiency.

Material and heat treatment guarantee

High-strength fasteners are only as good as their metallurgy. At Taiming, every 10.9-grade screw starts from verified alloy steel, undergoes controlled heat treatment, and is hardness-tested batch by batch. Raw material certificates and full test reports accompany every shipment.

Explore our high-strength screws or request a quote for automotive-grade fasteners.