Test Method for Measuring Adhesion of Organic Coatings to Plastic Substrates by Direct Tensile Testing

2002 ◽  
Author(s):  
Keyword(s):  
Tensile Testing ◽  
Test Method ◽  
Organic Coatings ◽  
Plastic Substrates ◽  
Direct Tensile

scholarly journals Determination of Direct Tensile Strength Values of Rock Materials by a New Test Method of Drilled Disc Tension

2019 ◽  
Author(s):  
Eren Komurlu ◽  
Serhat Demir
Keyword(s):  
Tensile Strength ◽  
Experimental Studies ◽  
Test Method ◽  
Uniaxial Tensile ◽  
Direct Tension ◽  
Rock Materials ◽  
Uniaxial Tensile Stress ◽  
Direct Tensile ◽  
Drill Holes ◽  
Direct Tensile Strength

Use of drilled disc specimens was investigated with both numerical and experimental studies to determine direct tensile strengths of rock materials. A new loading apparatus with rods to insert into the drill holes of discs has been designed and manufactured to supply tension by using the compression test presses. In addition to the use of popular compressive presses for direct tension, elimination of the gluing in the standard direct tensile strength test method is a significant advantage to make possible both hard and soft rocks to be tested. The Brazilian test discs with the diameter of NX size and length to diameter ratio of 0.5 were used in tests. Different loading apparatus designs were analyzed and ideal angle of contact between rock and the loading rods was assessed to be 50° within various choices investigated in this study. The drilled discs were determined to fail due to the crack initiation under the condition of uniaxial tensile stress distribution at sidewalls of the hole. In addition to the drilled disc tension test, standard direct tensile strength tests were also carried out to take as reference and compare the results obtained from different methods. According to the results of both numerical and experimental studies, an equation was suggested to determine uniaxial tensile strengths of drilled disc specimens with 20 mm hole diameter and the contact angle of 50°.

scholarly journals Ductile Compressive Behavior of Biomedical Alloys

Metals ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 60
Author(s):  
Christian Affolter ◽  
Götz Thorwarth ◽  
Ariyan Arabi-Hashemi ◽  
Ulrich Müller ◽  
Bernhard Weisse
Keyword(s):  
Tensile Testing ◽  
316L Stainless Steel ◽  
Test Procedure ◽  
Test Method ◽  
Compressive Behavior ◽  
Flow Curves ◽  
Discussion Section ◽  
Ductile Metals ◽  
Compressive Testing ◽  
Micro Indentation

The mechanical properties of ductile metals are generally assessed by means of tensile testing. Compression testing of metal alloys is usually only applied for brittle materials, or if the available specimen size is limited (e.g., in micro indentation). In the present study a previously developed test procedure for compressive testing was applied to determine the elastic properties and the yield curves of different biomedical alloys, such as 316L (two different batches), Ti-6Al-7Nb, and Co-28Cr-6Mo. The results were compared and validated against data from tensile testing. The converted flow curves for true stress vs. logarithmic strain of the compressive samples coincided well up to the yield strength of the tensile samples. The developed compression test method was shown to be reliable and valid, and it can be applied in cases where only small material batches are available, e.g., from additive manufacturing. Nevertheless, a certain yield asymmetry was observed with one of the tested 316L stainless steel alloys and the Co-28Cr-6Mo. Possible hypotheses and explanations for this yield asymmetry are given in the discussion section.

Measurements for the Moisture Permeations and Thermal Resistances of Cyclo Olefin Copolymer Substrates Deposited a Silicon Dioxide Film

2008 ◽  
Author(s):  
Rong-Yuan Jou
Keyword(s):  
Thermal Resistance ◽  
Silicon Dioxide ◽  
Diffusion Barrier ◽  
Moisture Diffusion ◽  
Permeation Rate ◽  
Test Method ◽  
Thermal Barrier ◽  
Silicon Dioxide Film ◽  
Plastic Substrates ◽  
Dioxide Film

Plastic substrates for organic light-emitting devices (OLED) are extremely sensitive to moisture and oxygen. A new amorphous engineering thermoplastic, nominated cyclic olefin copolymer (COC) has been used for this application, because of higher transparence, lower birefringence, lower dispersion and lower water absorption. However, COC plastic substrates can’t sustain plasma-based processing temperatures at 350°C. In this study, experiments of the moisture permeation rate testing and the thermal resistance experiments are conducted to explore the moisture diffusion barrier and thermal barrier characteristics of COC substrate deposited a SiO2 thin film on it. Silicon dioxide layer of thickness, 0.25μm, 0.5μm, and 1 μm, respectively, are fabricated by PECVD. For the permeation rate measurement, the Ca-test method is adopted. For the thermal resistance measurements, two methods of the thermocouple in vacuum environment and the IR thermography are adopted and measured results are compared. Different surface temperatures, 323.15K, 373.15K, 408.15K, and 473.15K, respectively, are applied upon the silicon dioxide film and temperature differences for varied thickness of silicon dioxide film are measured. Experimental results are presented to investigate the behaviors of moisture diffusion barrier and thermal barrier characteristics of the COC/SiO2 structure.

Sign in / Sign up

Export Citation Format

Share Document