同质异种热处理状态铝合金搅拌摩擦焊
接头组织与性能
郝云飞
毕煌圣
孙宇明
孙世炬
（首都航天机械公司，北京100076）
李延民
文摘开展了2219MCS叉形环和2219C10S筒段组成的接底接头的搅择摩擦焊工艺试验，分析了焊接速度、2219MCS叉形环位置对接头组织形貌、显微硬度、力学性能的影响规律。结果表明：2219MCS叉形环的原始粗大组织晶粒导致其无论位于前进侧还是后退侧，均是整个接头的薄弱环节。接头显微硬度呈现出典型的“W”型分布，叉形环一侧的热机影响区的显微硬度最低。在焊接参数相同时，叉形环位于后退侧的力学性能优于其位于前进侧；当焊接速度为180~220mm/min且叉形环为后退侧时，其接头综合性能最优，抗拉强度可达到330MPa，低温抗拉强度可达到420MPa，延伸率超过3.5%，正弯性能均可以达到180°无裂纹，但是 2219MCS母材开始出现裂纹，而背弯性能较差，并且背部裂纹沿着2219MCS热机影响区一侧起裂、扩展。
关键词2219MCS+2219C10S接底接头，搅拌摩擦焊接，微观组织，力学性能
中图分类号：TG4
D0I;10.3969/j.issn.10072330.2016.03.006
MicrostructureandMechanicalPropertiesof theFSWedJoints
Between2219MCSRingand2219C10SBarrel
HAOYunfei
SUNYuming
SUNShixuan
BIHuangsheng
(Capital Aerospace Machinery Company, Beijing100076)
LIYanmin
AbstractAn extensive investigation has been carried out on the friction stir welded butt joint consisting of a 2219MCS ring and a 2219C10S barrel, and the effect of welding speed and the location of the 2219MCS ring on the microstructure, microhardness distribution and mechanical properties of the butt joint has been systematically analyzed in this paper. The results showed that the 2219MCS ring whether located in the advancing side or retracting side is the weak link of the joint due to the original coarse grain. The microhardness distribution of the joint showed the typical"W" type with the TMAZ of the 2219MCS ring the lowest. The optimized investigation results showed that the per-formance of the joint with the 2219MCS ring located in the retracting side is more than the joint with the 2219MCS ring located in the advancing side. When the welding speed is 180 to 220 mm/min and the 2219MCS ring located in the retracting side, the room temperature mechanical strength can be up to 330 MPa, the low temperature strength 420 MPa, and the ductility all more than 3.5%. The face bending angle can reach 180° without crack on the joint, but some cracks occurred on the parent metal of the 2219MCS ring. The back bending performance is so poor, and the crack occurred and spreaded along the TMAZ of the2219MCS ring
Key wordsButt joint,2219MCS ring,2219C10S barrel,Friction stir welding,Microstructure,Mechanical property
0引言
运载火箭贮箱接底环缝是连接前（后）箱底叉形环与中间筒段的一条对接环缝，在飞行过程中承受较大的内压载荷，且其接底环缝两侧母材虽然同为
2219铝合金，但是热处理状态及母材组织存在很大差异，箱底叉形环为MCS状态，组织晶粒粗大，形状不规则；而中间筒段为C10S状态，组织呈细小板条状晶粒。前期国内诸多高校、宇航机构在2219C10S
收稿日期：201506-15；修回日期：20160308
作者简介：部云飞，1984年出生，颈士，工程师，主要从事授择摩擦焊、摩擦塞补焊、运载火资贮箱研制等工作。E-mail；haoyunfei1234@163.com
宇航材料工艺万方数据
http://www-yhclgy.com
2016年第3期
— 27 -