Influence of Akin singular element for intensity of stress singularity near interface edge of three
dimensional dissimilar material joints
Yutaro Watanabe Takahiko Kurahashi
Electrical mechanical advanced course Nagaoka University of Technology,
at Nagaoka National College of Technology 1603-1 Kamitomiokamachi, Nagaoka, 940-2188, Niigata 888 Nishikatakai, Nagaoka Niigata 940-8532, JAPAN [email protected]
Toshimi Kondo Hideo Koguchi
Nagaoka National College of Technology Nagaoka University of Technology,
888 Nishikatakai, Nagaoka, Niigata 940-8532, JAPAN 1603-1 Kamitomiokamachi, Nagaoka, 940-2188, Niigata [email protected] [email protected]
ABSTRACT
In this study, we report remarks for stress singularity field on interface of dissimilar material joints. In case that external force apply to dissimilar material joints as shown in Fig.1, stress component σ
zzincreases drastically near edge of interface. For stress singular problems, Akin suggested singular element around top of crack to obtain high accurate stress distribution near singular point. However, this singular element is applied to only two dimensional problems. Therefore, in this study, we extend dimension of the singular element to three dimensions, and examine influence of the three dimensional Akin singular element for stress singular field on interface of dissimilar material joints.
Fig.1 Image diagram of stress distribution near edge of interface
As the numerical model, the length of dissimilar material joint is 1mm, the width 1mm, and the height 3 mm. External forces is applied to upper material of dissimilar material joint and the value of external force is 10 MPa. In case of computational model made of Fe-Al, it is found that stress component
σzzwith Akin singular element is higher than normal element (Fig.2). Moreover, it is also found that order of singularity
λvertexobtained by least square method in case of Akin singular element is closer to order of singularity at vertex obtained by three dimensional finite element eigen analysis(Fig.3).
Fig.2 Distribution of σzz at line at φ =45 [deg] Fig.3 Variation of order of singularity ( Δh=8.04×10-3m) for each minimum mesh size
