Solder Ball Connect (SBC) assemblies under thermal loading: II. Strain analysis via image processing, and reliability considerations

Investigating full-field deformation of planar soft tissue under simple-shear tests

“…Normally, cross grating was put on specimen surface for 2-D strain analysis, the x-and y-direction displacement fields (u and v fields) can be established by using grating lines perpendicular to the x-and y-axes of a specimen, respectively. FTM (Morimoto et al, 1988(Morimoto et al, , 1989 and computational Fourier transform moire´(CFTM) (Choi et al, 1993) are two in-plane moire´techniques which utilize Fourier transform to automate the displacements and strain analyses. FTM can obtain the displacements and strains of a deformed body without the aid of the reference grating of in-plane moire´system.…”

“…However, a precise moire´interferometry system which can control the production of carrier fringes in the fringe pattern to produce a well-defined diffraction pattern is required. The advantages and disadvantages of FTM and CFTM are described in detail by Choi et al (1993). In current study, the Fourier transform moire´method was used to measure full-field deformation of porcine skin specimen during finite simple-shear tests as this method is suitable for strain analysis of materials which may undergo large deformation (Guo et al, 2005;Liou, 2004Liou, , 2005 and the experimental setup is simple.…”

Using Carrier Fringes to Study the High Temperature Deformation Behavior of a BGA Package Under Extended Dwell Times

“…Carrier fringes have been used in the past to better interpret the deformation data and to extract more detailed information from the deformation fringes [13][14][15]. They have also been used to obtain the strains in the solder joints [16]. Carrier fringes are introduced by a tiny adjustment of the angle of the incident laser beam on the grating specimen [8] and have an effect of introducing a constant strain in the specimen.…”

“…Once the phase information is obtained, the fringe counting accuracy of the U and V field fringe patterns can be increased n times by using the relations given in equations (15) and (16). These two relations are formulated based on the fact that the grey scale intensity displayed in an image varies between 0 to 255 [20].…”

A numerical investigation on the influence of full vs perimeter arrays on the mechanical reliability of electronic assemblies under vibration

“…Actually, peripheral (or perimeter) and full arrays are the most common types (Gharaibeh and Makhlouf, 2020). Numerous research investigations are available in literature on the deformations and fatigue performance of BGA solders in mechanical shock (Xu et al , 2016; Lin et al , 2016; García et al , 2018) and thermal cyclic loading conditions (Choi et al , 1993; Guo et al , 1993; Darveaux et al , 1995). For studies considering mechanical vibrations, Su et al (2014, 2018) presented a new vibration testing methodology, known as resonance tracking, and used it in the evaluation of the reliability and fatigue behavior of several lead-free BGA assemblies.…”