关键词: 铝合金门槛梁；高强度；轻量化；多级吸能；细化晶粒

Abstract: At the present stage, many new energy vehicles carried power batteries which are installed on the side sill beam. When the new energy vehicle encounters a side collision, it may lead to extremely dangerous accidents such as fire and explosion of the power battery in addition to causing injury to the personnel in the vehicle. Therefore, it is particularly important to improve the strength and energy absorption of the side sill beam of new energy vehicles. Aluminum alloy side sill beam with high strength and multi-stage energy absorption performance adopts the unique aluminum alloy formula from the raw material. The process procedure refines the alloy grain, and the innovative "目" shaped section structure is designed, so as to realize the timely collapsing and deformation during the collision process and absorb energy step by step by side sill beam,avoid transferring the collision energy to the structure inside and behind the vehicle. It not only realizes the lightweight of new energy vehicles, but also protects the safety of people and battery packs in limited space to the greatest extent. It can be widely used in the field of new energy vehicles,effectively promoting the technological progress and industrial upgrading for the new energy vehicle industry.

Key words: Aluminum alloy side sill beam; High strength; Lightweight; Multi-stage energy absorption; Grain refinement