In the design of new energy vehicle battery systems, 6061-T6 aluminum alloy plate has become the first choice for core materials of battery trays due to its high strength, light weight and process adaptability. The following is the key selection logic:
1. Impact resistance guarantee
Mechanical properties: After T6 heat treatment, the tensile strength reaches 310MPa and the yield strength reaches 276MPa, which can withstand the instantaneous impact load during vehicle collision and ensure the structural stability of the battery pack (comparison of measured data: the deformation resistance is 40% higher than that of 5052 aluminum).
Fatigue test: Passed SAE J2380 vibration test (1 million cycles) to verify its crack resistance under complex road conditions.
2. Welding process adaptability
MIG welding compatibility: 6061-T6 has a low grain coarsening rate in the heat affected zone (HAZ) of the solid solution state. With ER4043 welding wire, the weld strength can reach more than 85% of the parent material.
Friction stir welding (FSW) optimization: For large-size pallet splicing scenarios, the FSW process can eliminate pore defects, increase joint efficiency to 95% (traditional arc welding is only 75%), and significantly reduce the risk of leakage.
Application example: CATL CTP3.0 battery pack uses 6061-T6 one-piece die-cast pallet, which reduces weight by 15% and passes GB 38031 extrusion test certification. When selecting, focus on the aging stability of aluminum materials and the post-welding stress relief solution to avoid microcracks caused by long-term vibration.
