一、前言航空工业迅速发展,不仅要求高强度铝合金结构件的强度高,而且要有良好的综合性能,如抗应力腐蚀性能、抗疲劳性能及断裂韧性,特别是短横向上的韧性。就我们所知,LC4合金某些锻件的短横向上的伸长率及厚板的横向伸长率,长期以来处于技术标准的下限,并且有时不合格,给生产带来许多问题。高强度铝合金中的化合物质点,对韧性是有害的,因为它们在拉应力的作用下易断裂,从而造成裂纹源。LC4合金 I. Introduction The rapid development of the aviation industry requires not only the high strength of high-strength aluminum alloy structural parts, but also the good comprehensive properties such as stress corrosion resistance, fatigue resistance and fracture toughness, especially the short transverse tenacity. To the best of our knowledge, the short transverse elongation and the transverse elongation of some of the forgings of LC4 alloys have long been at the lower end of the technical standard and sometimes failed, posing a number of problems for production. High-strength aluminum alloy compound particles, the toughness is harmful, because they are easy to fracture under tensile stress, resulting in sources of cracks. LC4 alloy