汽车吸能盒用6063铝合金薄壁型材性能研究

Study on Properties of 6063 Aluminum Alloy Thin-wall Profiles for Automotive Crash Box

由于全球碳排放量日益严重,汽车行业走上了节能减排轻量化发展的道路,越来越多的铝挤压型材被广泛地应用到汽车构件中。国内外很多客户将材料T4态性能作为衡量铝合金材料的重要指标之一,现有的6063合金成分范围较广,但2.5 mm以下薄壁型材T4态性能无法达到6063-T4要求的R_(p)0.2≥70 MPa、R_(m)≥150 MPa和A_(g)≥20%。本文通过改变合金成分配比,将Si含量和Mg含量分别调整至0.4%~0.5%和0.5%~0.6%,并严格限定杂质Fe含量<0.17%。并通过调整挤压工艺参数及合理化模具设计的方法。试验表明:低温高速强淬火配合模具阻流式结构设计可满足挤压型材6063-T4的性能要求,时效后则达到了6063-T7的性能:R_(p)0.2为220~260 MPa,R_(m)≥240 MPa,A_(50)≥8%,各项性能指标的满足相关标准要求。

Due to the increasingly serious global carbon emissions,and the lightweight development trend of energy saving and emission reduction in the automotive industry,more and more aluminum extruded profiles are applied to the key parts of the automobile.Many customers at home and abroad take the material T4-state performance as one of the important indicators to measure aluminum alloy materials,the existing 6063 alloy has a wide composition range,the T4-state performance of the 2.5 mm below thin wall profile can not reach requirements of R_(p)0.2≥70 MPa,R_(m)≥150 MPa,A_(g)≥20%.In this paper,a new alloy isdeveloped by changing the alloy composition ratio,the Si content and Mg content are adjusted to 0.4%to 0.5%and 0.5%to 0.6%,respectively,the impurity Fe content is strictly limites to<0.17%,and the extrusion process parameters are adjusted and the mold design is rationalized.The results show that the low temperature,high speed and strong quenching combined with the die resistance flow structure design can meet the performance requirements of extruded profile 6063-T4,the aging performance of 6063-T7:R_(p)0.2 is 220 to 260 MPa,R_(m)≥240 MPa,A_(50)≥8%,all the performance indexes can meet the relevant standard requirements.