Effects of Cure State on the Ultrasonic Nonlinear Parameter in Adhesive Joints

2000 ◽  
Author(s):  
Guoli Liu ◽  
Jianmin Qu ◽  
Laurence J. Jacobs
Keyword(s):  
Narrow Band ◽  
Harmonic Signal ◽  
Adhesive Joints ◽  
Nonlinear Parameter ◽  
Curing Temperature ◽  
Curing Time ◽  
Curing Conditions ◽  
Polymer Adhesive ◽  
Ultrasonic Techniques ◽  
Transmitted Signal

Abstract The objective of this paper is to characterize the cure state of polymer adhesive joints using nonlinear ultrasonic techniques. To this end, through transmission tests were carried out on joint samples that had been subjected to various curing conditions. In these tests, a 40-cycle harmonic signal was generated by a 2MHz narrow-band PZT transducer as the incident wave. The wave transmitted through the adhesive joint was received with a 4MHz narrow-band PZT transducer. The magnitude of the second order harmonics in the transmitted signal was measured and the corresponding nonlinear parameter β was calculated. A fairly good correlation was observed between the nonlinear parameter and the cure state. It was found that under-curing (lower curing temperature or short curing time) tends to increase the nonlinear parameter.

Effect of Curing Regimes on Metakaolin Geopolymer Pastes Produced from Geopolymer Powder

2012 ◽  
Vol 626 ◽  
pp. 931-936 ◽  
Author(s):  
Liew Yun Ming ◽  
Kamarudin Hussin ◽  
Mohd Mustafa Al Bakri Abdullah ◽  
Mohammed Binhussain ◽  
Luqman Musa ◽  
...  
Keyword(s):  
Room Temperature ◽  
Raw Materials ◽  
Solidification Process ◽  
Curing Temperature ◽  
Alkali Concentration ◽  
Strength Development ◽  
Curing Time ◽  
Curing Conditions ◽  
Metakaolin Geopolymer ◽  
Geopolymer Paste

The properties of metakaolin geopolymer paste are affected by the alkali concentration, the initial raw materials, solidification process, and amount of mixing water as well as the curing conditions. This study aimed to investigate the effect of curing temperature (room temperature, 40°C, 60°C, 80°C and 100°C) and curing time (6h, 12h, 24h, 48h and 72h) on the geopolymer pastes produced from geopolymer powder. The results showed that curing at room temperature was unfeasible. Heat was required for the geopolymerization process, where strength increased as the curing temperature was increased. Moderate elevated curing temperature favored the strength development of geopolymer pastes in comparison with those treated with extreme elevated curing temperature. When geopolymer paste was subjected to extreme elevated curing temperature, shorter curing time should be used to avoid deterioration in strength gain. Similarly, longer curing time was recommended for moderate elevated curing temperature. The microstructure of geopolymer paste cured at moderate curing temperature showed obvious densification of structure. In contrast, the structure formed was weak and less compact at very high elevated curing temperature.

Effects of Curing Systems on the Strength and Microstructure of Reactive Powder Concrete with Iron Tailing Sands

2014 ◽  
Vol 548-549 ◽  
pp. 247-253
Author(s):  
Zhi Gang Zhu ◽  
Bei Xing Li ◽  
Jin Cheng Liu ◽  
Xing Dong Lv
Keyword(s):  
Point Of View ◽  
Hot Water ◽  
Curing Temperature ◽  
Reactive Powder Concrete ◽  
Curing Time ◽  
Submicroscopic Structure ◽  
Curing Conditions ◽  
The Difference ◽  
Reactive Powder ◽  
Curing Systems

To produce 130MPa reactive powder concrete with iron tailing sands as aggregation in an economic hot curing system, the effects of curing temperature, curing time and curing conditions on the reactive powder concrete was studied, the reasons of the strength of reactive powder concrete in different curing systems has the difference from the submicroscopic structure point of view was analyzed. The results show that use 90°C hot water to cure reactive powder concrete for 48h can lead it’s 28 day compressive strength reaches 140MPa, the flexural strength reaches 28MPa.

Investigation of Conductive Adhesive Bonding Using UV Curable Anisotropic Conductive Adhesives at Different Curing Conditions

2005 ◽  
Vol 127 (1) ◽  
pp. 52-58 ◽  
Author(s):  
K. K. Lee ◽  
S. C. Tan ◽  
Y. C. Chan
Keyword(s):  
Shear Test ◽  
Adhesive Bonding ◽  
Uv Light ◽  
Curing Temperature ◽  
Curing Time ◽  
Conductive Adhesives ◽  
Radical Initiation ◽  
Uv Curable ◽  
Curing Conditions ◽  
Adhesive Materials

Generally, adhesive materials can be cured in a short time under high curing temperature. High curing temperature usually leads to an increase in cross-link density and a homologous increase in heat resistance. Nevertheless, curing process under high temperature problems can occur such as the inclination for the adhesive materials to shrinkage, cracks, voids and it would probably lower the dielectric properties. UV curing of anisotropic conductive adhesives (ACAs) offers several advantages over the conventional epoxy resin, including rapid cure, little to no emission of volatile organic compounds and without affecting other components in the assembly [Pataki, W. S., 1997, “Optimization of Free-Radical Initiation Reactions in the Electrical Industry,” Electrical Insulation Conference and Electrical Manufacturing and Coil Winding Conference Proceedings, pp. 745–751]. Based on the aforementioned advantages, it is worth investigating the bonding properties at different curing conditions. In this work, a new type of UV curable ACA for chip-on-flex application is presented. The adhesive bonds of the chip-on-flex application are cured at different cure cycles within a range of UV frequencies. Cure cycles in this work were the different periods of time that were needed to cure the ACAs under different UV light intensities. Fourier transform infrared spectroscopy with attenuated total internal reflection was used to investigate the curing degree of the ACAs at different cure cycles. The result shows that the longer the curing time and the larger the UV intensity, the higher the curing degree can be obtained. Furthermore, the curing time in the UV curable ACA was much shorter than that of the conventional thermal curable ACAs. Shear test was done to find out the shear strength of the bonding. Finally, after shear test, scanning electron microscope was used to investigate the fracture mode of the chip-on-flex application at different curing cycles.

Optimization of the Uncooked Oratosquilla Oratoria Curing Process via Response Surface Methodology

2014 ◽  
Vol 1073-1076 ◽  
pp. 1793-1797
Author(s):  
Qi Wei Mao ◽  
Jun Rui Wu ◽  
Xi Qing Yue
Keyword(s):  
Pathogenic Bacteria ◽  
Raw Materials ◽  
Curing Temperature ◽  
Curing Process ◽  
Curing Time ◽  
Optimal Process ◽  
Curing Conditions ◽  
Oratosquilla Oratoria ◽  
Sensory Score ◽  
Total Bacteria

Oratosquilla oratoria was the experimental raw materials in the paper. Design expert8.0.6 and Excel2007 was used to analyze the optimal process with the factors which were curing time, curing temperature, curing salt contention and the index which was the total bacteria. The pathogenic bacteria and sensory score under various curing conditions were determined simultaneously. After analyzing the significance of the various factors and interactions, the results showed the optimum curing conditions of oratosquilla oratoria were as follows: curing time 7.14h, curing temperature 14.34°C, curing salt contention 8.3%. Under this condition no pathogenic bacteria was detected and the sensory score was the highest.

INFLUENCE OF CURING CONDITIONS AND ALKALI HYDROXIDE ON STRENGTH OF FLY ASH GEOPOLYMER CONCRETE

2014 ◽  
Vol 1 (1) ◽  
Author(s):  
Khoa Tan Nguyen ◽  
Tuan Anh Le ◽  
An Thao Huynh ◽  
Namshik Ahn
Keyword(s):  
Compressive Strength ◽  
Sodium Hydroxide ◽  
Carbon Dioxide Emissions ◽  
Building Materials ◽  
Sodium Hydroxide Solution ◽  
Curing Temperature ◽  
Geopolymer Concrete ◽  
Curing Time ◽  
Curing Conditions ◽  
Alkali Hydroxide

Geopolymer concrete is known as an alternative to Portland cement, with low carbon dioxide emissions compared with the conventional building materials. In this research, the influence of curing conditions and alkali hydroxide were investigated, using curing temperatures between 40 to 100℃, curing times from 4 to 12 hours, and various types of hydroxide and concentrations of sodium hydroxide solution. Geopolymerization needs energy and time to occur, and higher curing temperatures resulted in larger compressive strength, while longer curing times resulted in higher compressive strength. At the same curing temperature, longer curing time resulted in a higher compressive strength because the longer curing time extends the chemical reaction. For geopolymer concrete, sodium hydroxide is a better property than potassium hydroxide, because the atomic size of sodium anion is smaller than potassium. Further, the strength of concrete increased when the concentration of sodium hydroxide increased. In conclusion, geopolymer concrete is suitable for traditional building materials. Finding renewable materials to satisfy the increasing demand for building structures will be the primary challenge in future.

scholarly journals Differences of Curing Effects between a Human and Veterinary Bone Cement

Materials ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 470 ◽  
Author(s):  
K. Kallol ◽  
M. Motalab ◽  
M. Parvej ◽  
P. Konari ◽  
H. Barghouthi ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Shear Strength ◽  
Mechanical Behavior ◽  
Bone Cement ◽  
Curing Temperature ◽  
Interface Fracture ◽  
Curing Time ◽  
Curing Conditions ◽  
Curing Characteristics ◽  
Significant Difference

The goal of the study is to understand how the curing characteristics of a human bone cement (HBC) and veterinary bone cement (VBC) influence the mechanical behavior of each cement and cement bonding with an implant. This study hypothesizes that the curing temperature and time influence the mechanical properties of the cement adjacent to the implant, which resulted in the variability in bonding strength between the implant and cement. To test this hypothesis, this study measured the exothermic temperature, flexural strength, hardness, and morphology of a HBC and VBC at different curing times. In addition, this study measured shear strength at the interfaces of implant/HBC and implant/VBC samples during static and stepwise cyclic tests at different curing times. This study used Stryker Simplex P and BioMedtrix 3 poly methyl methacrylate (PMMA) as an HBC and VBC, respectively. This study cured HBC and VBC cement for 30 and 60 min and then conducted flexural, hardness, and interface fracture tests to evaluate the curing effect on mechanical behavior of each of the cements. This study found that the curing time significantly increases the values of flexure and hardness properties of each cement and shear strength of implant/HBC and implant/VBC (p < 0.05). This study observed a difference of curing time and temperature between HBC and VBC. This study also observed a significant difference of surface porosity at the interface of implant/HBC and implant/VBC interfaces. The variability of mechanical properties between HBC and VBC due to the differences of curing conditions may influence the bonding of cement with the implant.

The Study of the Affect Factors on the Soaping Fastness Resistance of Inkjet Ink

2012 ◽  
Vol 200 ◽  
pp. 698-701
Author(s):  
Ji Fang Yan ◽  
Bei Qing Huang ◽  
Xian Fu Wei
Keyword(s):  
Particle Size ◽  
Inkjet Printing ◽  
Binder Content ◽  
Curing Temperature ◽  
Color Fastness ◽  
Curing Time ◽  
Curing Conditions ◽  
Water Based ◽  
Curing Condition ◽  
Printing Ink

This paper is to study factors that affect soaping color fastness of inkjet printing ink. Considering ink as a constant, discuss the affect of curing conditions on soaping fastness by altering curing temperature and curing time. Considering curing condition as a constant, study the affect of other factors on soaping fastness of ink, like particle size, the binder content and varieties of binder. The results show that: the soaping fastness is better when the curing temperature is 180°Cand curing time is 3minites; The smaller the particle size of ink is, the higher the soaping fastness is; the soaping fastness is well when the binder content of ink accounts for 20% of the total. The water-based polyacrylate and water-based polyurethane have the same effects on soaping fastness.

scholarly journals Optimization of Manufacturing Parameters of 3D Printed Solid Microneedles for Transdermal Drug Delivery

2021 ◽  
Vol 4 (1) ◽  
pp. 22
Author(s):  
Kenan Muhamedagić ◽  
Amina Tucak ◽  
Merima Sirbubalo ◽  
Ognjenka Rahić ◽  
Lamija Hindija ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Transdermal Drug Delivery ◽  
Isopropyl Alcohol ◽  
Low Cost ◽  
Curing Temperature ◽  
Curing Time ◽  
Curing Conditions ◽  
3D Printed ◽  
Fracture Tests ◽  
Manufacturing Parameters

Microneedles (MNs) have been manufactured using a variety of methods from a range of materials, but most of them are expensive and time-consuming for screening new designs and making any modifications. Therefore, stereolithography (SLA) has emerged as a promising approach for MN fabrication due to its numerous advantages, including simplicity, low cost, and the ability to manufacture complex geometrical products at any time, including modifications to the original designs. This work aimed to print MNs using SLA technology and investigate the effects of post-printing curing conditions on the mechanical properties of 3D-printed MNs. Solid MNs were designed using CAD software and printed with grey resin (Formlabs, UK) using a Form 3 printer (Formlabs, UK). MNs dimensions were 1.2 × 0.4 × 0.05 mm, arranged in 6 rows and 6 columns on a 10 × 10 mm baseplate. MNs were then immersed in an isopropyl alcohol bath to remove unpolymerized resin residues and cured in a UV-A heated chamber (Formlabs, UK). In total, nine samples were taken for each combination of curing temperature (35, 50, and 70 °C) and curing time (5, 20, and 60 min). Fracture tests were conducted using a hardness apparatus TB24 (Erweka, Germany). MNs were placed on the moving probe of the machine and compressed until fracture. The optimization of the SLA process parameters for improving the strength of MNs was performed using the Taguchi method. The design of experiments was carried out based on the Taguchi L9 orthogonal array. Experimental results showed that the curing temperature has a significant influence on MN strength improvements. Improvement of the MN strength can be achieved by increasing the curing temperature and curing time.

The Study of the Affect Factors on Color Fastness to Crocking of Inkjet Ink

2012 ◽  
Vol 262 ◽  
pp. 543-546
Author(s):  
Ji Fang Yan ◽  
Bei Qing Huang ◽  
Xian Fu Wei
Keyword(s):  
Inkjet Printing ◽  
Curing Temperature ◽  
Color Fastness ◽  
Curing Time ◽  
Curing Conditions ◽  
Water Based ◽  
Printing Ink ◽  
Better Than

This paper is to determine the effects of various factors on the color fastness to crocking of inkjet printing ink. Firstly, the affects of curing conditions on color fastness to crocking were discussed by altering curing temperature and curing time separately. Secondly, considering curing conditions as a constant, study the affects of the pH of ink, the amount of adhesives and the varieties of adhesives on color fastness to crocking by changing these factors respectively. The results show that: the color fastness to crocking of printing fabric is better when curing temperature is 1800C and curing time is 90s; the wet crocking fastness of printing fabric declined as the pH of ink increased; the color fastness to crocking of fabric printed with ink which prepared use water-based polyurethane is better than use water-based polyacrylate.

scholarly journals Experimental Investigation of the Technical Performances of SRX-Stabilized Graded Macadam

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Na Xu ◽  
Zhongda Chen ◽  
Haijun Gao ◽  
Dingming Dong ◽  
Yongjun Wu ◽  
...  
Keyword(s):  
Resilient Modulus ◽  
Curing Temperature ◽  
Strength Ratio ◽  
Curing Time ◽  
Curing Conditions ◽  
Freeze Thaw ◽  
Technical Requirements ◽  
Test Efficiency ◽  
Content Variation ◽  
Shrinkage Coefficient

The technical performances of Solution Road RomixSoilfix- (SRX-) stabilized graded macadam (SSGM) are investigated to promote its application. The specimen curing conditions were proposed to improve the test efficiency by analyzing the influence of curing temperature on the unconfined compressive strength and moisture content variation. Moreover, the mechanical properties (e.g., CBR, strength, and resilient modulus) and pavement performances (e.g., temperature shrinkage, water stability, and freezing stability) of SSGM were evaluated through laboratory tests. The results show that the recommended curing temperature in the drying oven should be 100°C ± 2°C and the recommended curing time should not be less than 16 h. Furthermore, the CBR, unconfined compressive and splitting strengths, and resilient modulus of SSGM increase with the content of SRX stabilizer. The temperature shrinkage coefficient is approximately 15% of the cement-stabilized grading crushed stone. The dry-wet recovery strength ratio is approximately 96% after four dry-wet cycles. The freeze-thaw recovery strength ratio is approximately 58% after five freeze-thaw cycles. The freezing stability of SSGM can be improved by increasing the content of SRX stabilizer. The technical performances of SSGM should fulfill the technical requirements.

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