An Experimental Study on the Strength of Aluminum Honeycomb Sandwich Joints Under Pull-Out Loading

2012 ◽  
Vol 15 (1) ◽  
pp. 321-325 ◽  
Author(s):  
Yong-Bin Park ◽  
Jin-Hwe Kweon ◽  
Jin-Ho Choi
2018 ◽  
Vol 108 (05) ◽  
pp. 353-358
Author(s):  
E. Abele ◽  
F. Ali ◽  
M. Berger

Aus Schwerzerspanung und Turbinenschaufelfertigung ist bekannt, dass Werkzeuge aus dem Spannfutter ausgezogen werden. Die veränderte Werkzeugposition führt zur Abweichung von den vorgegebenen Toleranzen und einer geringeren Fertigungsqualität oder Beschädigung des Werkstücks. Der Artikel untersucht das Auszugsverhalten verschiedener Spannfutter. Mit einem Prüfstand können die Einflüsse der mechanischen Belastung und der Klemmlänge auf die Haltekraft im Pressverband betrachtet und die Wirkmechanismen beim Auszug des Werkzeuges aus dem Spannfutter sensorisch ermittelt werden.   From heavy-duty cutting and turbine blade manufacturing it is known that tools pull out from chucks. A change in tool position leads to deviations from tolerance and decreases manufacturing quality or damages the workpiece. This article explores the extension behavior of different chucks on a specifically designed test bench. This allows determining how mechanical load and clamping length influence the holding force in the press fit and what mechanisms of action affect the extraction of the tool from the chuck.


2013 ◽  
Vol 2013 ◽  
pp. 1-20 ◽  
Author(s):  
Chang Qi ◽  
Shu Yang ◽  
Dong Wang ◽  
Li-Jun Yang

The dynamic responses of honeycomb sandwich panels (HSPs) subjected to in-plane projectile impact were studied by means of explicit nonlinear finite element simulations using LS-DYNA. The HSPs consisted of two identical aluminum alloy face-sheets and an aluminum honeycomb core featuring three types of unit cell configurations (regular, rectangular-shaped, and reentrant hexagons). The ballistic resistances of HSPs with the three core configurations were first analyzed. It was found that the HSP with the reentrant auxetic honeycomb core has the best ballistic resistance, due to the negative Poisson’s ratio effect of the core. Parametric studies were then carried out to clarify the influences of both macroscopic (face-sheet and core thicknesses, core relative density) and mesoscopic (unit cell angle and size) parameters on the ballistic responses of the auxetic HSPs. Numerical results show that the perforation resistant capabilities of the auxetic HSPs increase as the values of the macroscopic parameters increase. However, the mesoscopic parameters show nonmonotonic effects on the panels' ballistic capacities. The empirical equations for projectile residual velocities were formulated in terms of impact velocity and the structural parameters. It was also found that the blunter projectiles result in higher ballistic limits of the auxetic HSPs.


2019 ◽  
Vol 90 (3) ◽  
pp. e17.3-e16
Author(s):  
D Akarca ◽  
A Durnford ◽  
F Ewbank ◽  
J Hempenstall ◽  
A Sadek ◽  
...  

ObjectivesExternal ventricular drain (EVD) dislodgement is common and can lead to significant morbidity and mortality. UK trial data suggests dislodgement as high as 12%. This study aimed to establish the range of methods used nationally and determine the most secure method in a porcine model.DesignSurvey and experimental study.Subjects23 neurosurgical units surveyed. Porcine cadaver experimental model.MethodsSurvey distribution was made through the British Neurosurgical Trainee Research Collaborative. 15 securement methods were tested on the porcine model and peak pull-out force before EVD failure was measured. Failure was defined as catheter displacement 1 cm from the insertion site, catheter fracture or suture fracture.ResultsNationally, five EVD securement methods were in common use. There were considerable differences in peak pull-out force between methods. The most secure methods were a construct consisting of anchoring suture, further multiple sutures around a coil of catheter followed by either a soft (25.85N, 95% CI 24.95 N-26.75N) or hard plastic flange (29.05N, 95% CI 25.69 N-32.41N). Individually, anchoring sutures, soft flanges, VentriFix and staples were least secure, whilst multiple sutures and hard flanges were most secure.ConclusionsAn anchoring suture followed by a coil of catheter and a flange is the most secure method for securing EVDs, withstanding up to 8.2 times the force of a single anchoring suture. It is easily employed and may decrease the likelihood of EVD dislodgement and associated complications.


Author(s):  
Byung Il Kim ◽  
Byeong Wook Noh ◽  
Young Woo Choi ◽  
Sung In Bae ◽  
Jung Il Song

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