• Journal of Technologic Dentistry
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• v.21 no.1
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• pp.55-65
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• 1999

So far, I Conducted an examination with focus on the type, characteristic, and test methods of impact test. which is a type of mechanical that evaluate materials. As mentioned previously, in testing soldering strength of soldering is the load when the object under experiment is broken down with the result of flexibility test or peel test. In this method, a hevay load is necessary until alloy of parent metal is bended, if the alloy of the parent metal has a large mechanical quality(peel strength or resisting power). Once the alloy of the parent metal is bended, however, it tends to come into pieces abruply form the part where soldered. Therefore, a metal has a high breakdown value if the degree of strength of its parent metal is high even if the result of measurement indicates otherwise. Thus, the result of the test did not correspond to the clinical result. Therefore, this study concludes as the following from a test of strength of soldering by mean of conducting an impact test, which is a type of mechanical evaluation methods : 1. Among various impact tests, a charpy thpe is more appropriate than the izod type in testing strength of soldering. 2. As far as test piece is concerned, to use subsized impact test piece is appropriate in the impact test in that it does not have notch. 3. In the matter of analysis, it is appropriate to measure absorbing energy which results from rupture of test piece.

• Korean Journal of Poultry Science
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• v.11 no.2
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• pp.93-98
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• 1984

Four different silages were prepared out of citrus peel with or without supplementation with wheat bran and/or urea. Proximate nutrients and volatile fatty acids were analysed on the silages, both fresh and dried. All silages were dried and ground, and were compared with dried citrus peel (not ensiled) and wheat bran in a folding trial. A total of 360 male chicks of Maniker broiler strain was divided into and assigned to 6 treatments with 5 replications. Each experimental diet included each of 6 test material at the level of 6% and the feeding trial lasted 8 weeks, after which a metabolism trial was conducted. Results obtained were summarized as follows. 1. Ensiling increased protein content of the citrus peel on the dry matter basis and supplementing the silage material with wheat bran and/or urea further increased protein contents of the silages. 2. Adding wheat bran and/or urea to silage material also increased volatile fatty acid contents of the silages. After drying organic acid contents of the silages were reduced and there were no differences in organic acid contents of the dried citrus peel silages, differently treated, 3, Broilers fed dried citrus peel and those fed dried citrus peel silages gained numerically less weight than those fed wheat bran. But there were no significant differences in body weight gain, feed intake and feed efficiency among different treatments 4. There were no significant differences in nutrient utilizability, nitrogen retention and metabnlizable energy contents among treatments. It could be concluded that ensiling is an effective way of storing citrus peel and dried citrus peel silage could be used in broiler diets up to 6% without adverse effects.

• International Journal of Aerospace System Engineering
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• v.1 no.1
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• pp.16-20
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• 2014

Recently, various kinds of study on light weight structure are performing in the world. The Al honeycomb sandwich structural type adopt for improvement of lightness and structural stability to major part structure of aircraft or spacecraft. Adhesion badness properties of adhesive and adhesion properties of fillet mainly studied about al honeycomb structure. But study for adhesive properties of sandwich construction with surface treatment of Aluminum alloy barely performed. In this study, adhesive film was used between Al and honeycomb core of honeycomb panel[1]. The study for adhesive properties of sandwich construction with surface treatment of AA 5052 skin was performed.

• Elastomers and Composites
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• v.51 no.3
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• pp.181-187
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• 2016

Transparent acrylic pressure sensitive adhesives (PSAs) were successfully prepared by photopolymerization with 2-ethylhexyl acrylate (2-EHA) and 2-hydroxyethyl acrylate (2-HEA) as a default constituent and with isobornyl acrylate (IBOA) and N-(isobutoxymethyl)acrylamide (IBMA) as a variable constituent. The IBMA mole fraction effect in the acrylic PSAs was investigated on adhesion performances and the optical properties including 85/85 test as well as the characteristics (solid content, and molecular weight) of the PSA syrups were also investigated. Regardless increasing the IBMA mole fraction in the acrylic PSAs, the acrylic PSAs exhibited almost the same adhesion performance such as $180^{\circ}$ peel strength (~4.0 kg/25 mm) and probe tack (~0.27 kg). All the acrylic PSA samples also showed high transmittance (more than 91%), low haze (less than 1.0%) and low color-difference (less than 1.0) before and after 85/85 test.

• Proceedings of the Materials Research Society of Korea Conference
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• 2007.05a
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• pp.16.2-16.2
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• 2007

• Korean Journal of Materials Research
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• v.18 no.9
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• pp.486-491
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• 2008

The effect of annealing treatment conditions on the interfacial adhesion energy between electrolessplated Ni film and polyimide substrate was evaluated using a $180^{\circ}$ peel test. Measured peel strength values are $26.9{\pm}0.8,\;22.4{\pm}0.8,\;21.9{\pm}1.5,\;23.1{\pm}1.3,\;16.1{\pm}2.0\;and\;14.3{\pm}1.3g/mm$ for annealing treatment times during 0, 1, 3, 5, 10, and 20 hours, respectively, at $200^{\circ}C$ in ambient environment. XPS and AES analysis results on peeled surfaces clearly reveal that the peeling occurs cohesively inside polyimide. This implies a degradation of polyimide structure due to oxygen diffusion through interface between Ni and polyimide, which is also closely related to the decrease in the interfacial adhesion energy due to thermal treatment in ambient conditions.

• Journal of the Korean institute of surface engineering
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• v.26 no.2
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• pp.71-81
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• 1993

Thed effects of Ar or Oxygen RF plasma treatment on the adhesion behavior of Cr films to polyimide sub-strates have been investigated by using SEM, XRD, AES, and $90^{\circ}$peel test. By applying RF plasma treatment of the polyimide surface prior to metal deposition, the peel adhesion strength of Cu/Cr films sputtered onto the fully cured BPDA-PDA polyimide was highly increased from about 3g/mm to 90 ~ 100g/mm. Improved peel adhesion strength of Cr/polyimide interfaces due to RF plasma treatment was attributed to the contributions from surface cleaning, Cr-polyimide bonding at the interface, and force required for plastic deformation of the film. While the surface topology change of the polyimide caused by RF plasma treatment makes a little contri-bution to the improved adhesion.

• Bulletin of the Korean Chemical Society
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• v.28 no.2
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• pp.188-192
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• 2007

In this work, the effects of chemical treatment of polyimide films were studied by FT-IR, X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and contact angles. The adhesion characteristics of the films were also investigated in the peel strengths of polyimide/aluminum films. The increases of surface functional groups of KOH-treated polyimide films were greatly correlated with the polar component of surface free energy. The peel strength of polyimides to metal substrate was also greatly enhanced by increasing the KOH treatment time, which can be attributed to the formation of polar functional groups on the polyimide surfaces, resulting in enhancement of the work of adhesion between polymer film and metal plate.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.6
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• pp.166-173
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• 1998

The evaluation of joint fatigue strength of light weight materials for an electrical vehicle body has been performed through T-peel joint tests with the design parameters such as joint style, adherend type, adherend thickness, adhesive thickness, and various adhesives. Fatigue strength was evaluated through 5-Hz, tension-tension, load controlled test with the zero stress ratio. It was observed that the fatigue strength of the joint increases with the increase of the adherend thickness. With the increase of the adhesive thickness, however, the fatigue strength of the joint increases insignificantly. An aluminum-FRP adherend combination shows much higher fatigue strength than an aluminum-aluminum adherend combination. The results of fatigue tests were found to be consistent with those of static tests.

• Journal of the Korean institute of surface engineering
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• v.26 no.6
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• pp.327-333
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• 1993

The effect of heat treatment on the adhesion between Cu-18wt% Cr film and polyimide has been studied by using T-peel test, AES, and XRD. Cu-18wt% Cr alloy and pure Cu films were sputter deposited onto pol-yimide. Cu was electroplated before and after heat treatment at $400^{\circ}C$ for 0.5 hr and 2 hrs respectively. The adhesion of metal film onto polyimide was considerably good before heat treatment, but heat treatment re-duced the peel adhesion strength in all specimens. The reduction in adhesion in adhesion strength values in the specimens which were plated after heat treatment was mainly due to Cr-O rich pahse formed in the metal/polyimide in-terface. In the specimens which were heat treated after plating, the enhanced ductility in the metal films con-tributes the peel adhesion strength by increasing the amount of deformation in metal strips.