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We perform uniaxial tensile tests on polyimide-supported copper films with a strong (111) fiber texture and with thicknesses varying from 50 nm to 1 μm. Films with thicknesses below 200 nm fail by intergranular fracture at elongations of only a few percent. Thicker films rupture by ductile transgranular fracture and local debonding from the substrate. The failure strain for transgranular fracture exhibits a maximum for film thicknesses around 500 nm.

 Closed!!!

Two positions for guest researchers(post-doc) at NIST on biomechanics

Email: martin.chiang [at] nist.gov (martin[dot]chiang[at]nist[dot]gov)

Homepage: http://www.nist.gov/msel/polymers/biomaterials/martin_chiang.cfm

Research area: Biomechanics

I have had some time to write down an informal introduction to Moving Least Squares, from my coding perspective. It is supposed to be a condensation of experiences after some years of using it, although it does not contain any new theoretical aspect.

http://www.scribd.com/doc/19409754/yanrMLS

  Dear everyone

  If we considerer a 3D fracture stress and strain field as a combination of numerous 2D fields in thickness direction, the J integral at each 2D plane can be obtained according to Rice’s definition (Abaqus and Ansys also include this function). What I concerned is the ratio of J integral at the surface of SEB or CT specimen to that at the mid-plane of the specimen. What factors have influence on the ratio? How to find the quantitive relationship between the factors and the ratio in linear elastic model?

Worth reading

 http://www.dpmms.cam.ac.uk/~wtg10/continuity.html

in case you need to explain the epsilon-delta  definition of continuity to an engineering student.

-- Biswajit 

The Department of Mechanical Engineering at the Universitat Rovira i Virgili (URV) (www.urv.cat) in Tarragona (Spain), is looking for several enthusiastic research students with a strong interest in fluid dynamics. Successful candidates will join a small but very active multidisciplinary team, working in fluid-structure interaction problems. The research will be mainly experimental and focused in the area of fluid structure interaction with application to several engineering problems.

I would like to know why ABAQUS is the dominant FEM program (in terms of comments) in this forum? Why do you consider ABAQUS over ANSYS?

I have been using ANSYS for at least 8 years and I am very please with the capabilities of it. But I have not seen ABAQUS or used it. Beside, reading all the comments that are posted in imechanica, I feel like I am using the wrong FEM program. 

Which are the advantage of ABAQUS over ANSYS?

Thank you,

 Mario J . Juha