On the formation of onion rings in friction stir welds

被引：442

作者：

Krishnan, KN ^{[1
]}

机构：

[1] Univ Adelaide, Dept Mech Engn, CRC Welded Struct, Adelaide, SA 5005, Australia

来源：

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING | 2002年 / 327卷 / 02期

关键词：

onion rings; friction stir welding; welding; aluminium; extrusion; friction;

D O I：

10.1016/S0921-5093(01)01474-5

中图分类号：

TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

Onion rings are the most prominent features of most friction stir welds. The origin and the effect of these on properties are not clearly understood. In this paper, an attempt has been made to explain the formation of onion rings. The formation of onion ring is found to be a geometric effect due to the fact that cylindrical sheets of material are extruded during each rotation of the tool and the cutting through the section of the material produces an apparent 'Onion Rings'. It is postulated that the tool appears to wait for a very short time to produce frictional heat and extrude a cylindrical shaped material around to the retreating side of the joint. The spacing of the markings has been found to be equal to the forward motion of the tool in one rotation. (C) 20021 Elsevier Science B.V. All rights reserved.

引用

页码：246 / 251

页数：6