Improving the fracture toughness and the cyclic-fatigue resistance of epoxy-polymer blends

Abstract CYCLOPS N-9 is a chromium-nickel oil hardening steel with high toughness and fatigue resistance. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on forming, heat treating, machining, and joining. Filing Code: TS-71. Producer or source: Cyclops Corporation.

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Effect of sodium hypochlorite on the cyclic fatigue resistance: A scanning electron microscopy evaluation

Microscopy Research and Technique ◽

10.1002/jemt.23381 ◽

2019 ◽

Vol 82 (12) ◽

pp. 2089-2094 ◽

Cited By ~ 5

Author(s):

İhsan F. Ertuğrul

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Fatigue Resistance ◽

Sodium Hypochlorite ◽

Cyclic Fatigue ◽

Scanning Electron Microscopy Evaluation ◽

Scanning Electron

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Effect of synchronous irrigation on cyclic fatigue of nickel-titanium instrument in the dynamic and static models

Journal of Applied Biomaterials & Functional Materials ◽

10.1177/2280800020987403 ◽

2021 ◽

Vol 19 ◽

pp. 228080002098740

Author(s):

Haiyun Liu ◽

Yanfeng Li ◽

Guangquan Chai ◽

Yuan Lv ◽

Changjian Li ◽

...

Keyword(s):

Fatigue Resistance ◽

Flow Rate ◽

Dynamic Control ◽

Cyclic Fatigue ◽

Nickel Titanium ◽

Control Group ◽

Time To Failure ◽

Dynamic Tests ◽

Significant Difference ◽

Experimental Group

Objective: To evaluate the effect of synchronous water irrigation on the fatigue resistance of nickel-titanium instrument. Methods: A standardized cyclic fatigue test models were established, and five types of nickel-titanium instruments (PTU F1, WO, WOG, RE, and M3) were applied. Each instrument was randomly divided into two groups ( N = 12). There was synchronous water irrigation in the experimental group, and no water irrigation in the control group. Besides, ProTaper Universal F1 was randomly divided into 10 groups ( N = 20). In the static group, nickel-titanium instruments were divided into one control group (no irrigation, N = 20) and six experimental group (irrigation, N = 20) based on different flow rate, angle and position; while in the dynamic group, instruments were divided into one control group (no irrigation, N = 20) and two experimental group (irrigation, N = 20) based on different flow rate. The rotation time (Time to Failure, TtF) of instruments was recorded and analyzed. Results: According to the static experiments, the TtF of instruments in all experimental groups was significantly higher than that in the static control group. Besides, the dynamic tests of PTU F1 showed that the TtF in the experimental group was significantly higher than that in the dynamic control group. Compared with control group, the TtF in the experimental groups increased by at least about 30% and up to 160%. The static and dynamic tests of PTU F1 showed that the TtF of nickel-titanium instrument in all experimental groups was significantly higher than that in the control group. However, there was no significant difference between any two experimental groups. Conclusion: Regardless of dynamic or static model, TtF with irrigation was longer than that with non-irrigation, indicating that synchronous irrigation can increase the fatigue resistance of nickel-titanium instrument. However, different irrigation conditions may have the same effect on the fatigue resistance.

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Tension-Tension Fatigue Behavior of High-Toughness Zr61Ti2Cu25Al12 Bulk Metallic Glass

Materials ◽

10.3390/ma14112815 ◽

2021 ◽

Vol 14 (11) ◽

pp. 2815

Author(s):

Yu Hang Yang ◽

Jun Yi ◽

Na Yang ◽

Wen Liang ◽

Hao Ran Huang ◽

...

Keyword(s):

Fracture Toughness ◽

Shear Band ◽

Metallic Glass ◽

Bulk Metallic Glass ◽

Fatigue Resistance ◽

Metallic Glasses ◽

Stress Amplitude ◽

Fatigue Behavior ◽

Bulk Metallic Glasses ◽

High Toughness

Bulk metallic glasses have application potential in engineering structures due to their exceptional strength and fracture toughness. Their fatigue resistance is very important for the application as well. We report the tension-tension fatigue damage behavior of a Zr61Ti2Cu25Al12 bulk metallic glass, which has the highest fracture toughness among BMGs. The Zr61Ti2Cu25Al12 glass exhibits a tension-tension fatigue endurance limit of 195 MPa, which is higher than that of high-toughness steels. The fracture morphology of the specimens depends on the applied stress amplitude. We found flocks of shear bands, which were perpendicular to the loading direction, on the surface of the fatigue test specimens with stress amplitude higher than the fatigue limit of the glass. The fatigue cracking of the glass initiated from a shear band in a shear band flock. Our work demonstrated that the Zr61Ti2Cu25Al12 glass is a competitive structural material and shed light on improving the fatigue resistance of bulk metallic glasses.

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Mechanical and Morphological Properties of Bio-Phenolic/Epoxy Polymer Blends

Molecules ◽

10.3390/molecules26040773 ◽

2021 ◽

Vol 26 (4) ◽

pp. 773

Author(s):

Ahmad Safwan Ismail ◽

Mohammad Jawaid ◽

Norul Hisham Hamid ◽

Ridwan Yahaya ◽

Azman Hassan

Keyword(s):

Mechanical Properties ◽

Phase Separation ◽

Polymer Blends ◽

Epoxy Polymer ◽

Flexural Modulus ◽

Polymeric Materials ◽

Morphological Properties ◽

Comparison Results ◽

Unique Material ◽

Different Types

Polymer blends is a well-established and suitable method to produced new polymeric materials as compared to synthesis of a new polymer. The combination of two different types of polymers will produce a new and unique material, which has the attribute of both polymers. The aim of this work is to analyze mechanical and morphological properties of bio-phenolic/epoxy polymer blends to find the best formulation for future study. Bio-phenolic/epoxy polymer blends were fabricated using the hand lay-up method at different loading of bio-phenolic (5 wt%, 10 wt%, 15 wt%, 20 wt%, and 25 wt%) in the epoxy matrix whereas neat bio-phenolic and epoxy samples were also fabricated for comparison. Results indicated that mechanical properties were improved for bio-phenolic/epoxy polymer blends compared to neat epoxy and phenolic. In addition, there is no sign of phase separation in polymer blends. The highest tensile, flexural, and impact strength was shown by P-20(biophenolic-20 wt% and Epoxy-80 wt%) whereas P-25 (biophenolic-25 wt% and Epoxy-75 wt%) has the highest tensile and flexural modulus. Based on the finding, it is concluded that P-20 shows better overall mechanical properties among the polymer blends. Based on this finding, the bio-phenolic/epoxy blend with 20 wt% will be used for further study on flax-reinforced bio-phenolic/epoxy polymer blends.

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Influence of surrounding temperature and angle of file access on cyclic fatigue resistance of two single file nickel‐titanium instruments

Australian Endodontic Journal ◽

10.1111/aej.12473 ◽

2020 ◽

Author(s):

Giusy Rita Maria La Rosa ◽

Carlotta Palermo ◽

Sebastiano Ferlito ◽

Gaetano Isola ◽

Francesco Indelicato ◽

...

Keyword(s):

Fatigue Resistance ◽

Cyclic Fatigue ◽

Nickel Titanium ◽

File Access ◽

Single File

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Shaping and Centering Ability, Cyclic Fatigue Resistance and Fractographic Analysis of Three Thermally Treated NiTi Endodontic Instrument Systems

Materials ◽

10.3390/ma13245823 ◽

2020 ◽

Vol 13 (24) ◽

pp. 5823

Author(s):

Saulius Drukteinis ◽

Vytaute Peciuliene ◽

Ruta Bendinskaite ◽

Vilma Brukiene ◽

Rasmute Maneliene ◽

...

Keyword(s):

Fatigue Resistance ◽

Cyclic Fatigue ◽

Fractographic Analysis ◽

Significance Level ◽

Root Canals ◽

Topographic Features ◽

New Instrument ◽

Before And After ◽

Number Of Cycles ◽

Thermally Treated

The better understanding of the clinically important behavioral features of new instrument systems has an important significance for the clinical endodontics. This study aimed to investigate the shaping and centering ability as well as cyclic fatigue resistance of HyFlex CM (CM), HyFlex EDM (EDM) and EdgeFile (EF) thermally treated nickel–titanium (NiTi) endodontic instrument systems. Sixty curved root canals of the mesial roots of mandibular molars were randomly assigned into three groups (n = 20) and shaped using CM, EDM and EF files up to the size 40 and taper 04 of the instruments. µCT scanning of the specimens before and after preparation was performed and the morphometric 2D and 3D parameters were evaluated in the apical, middle and coronal thirds of root canals. In each group, 40.04 instruments (n = 20) were subjected to the cyclic fatigue resistance test in artificial root canals at 37 °C temperature until fractures occurred, and the number of cycles to failure (NCF) was calculated. The fractographic analysis was performed using a scanning electron microscope, evaluating topographic features and surface profiles of the separated instruments. The one-way analysis of variance with post hoc Tuckey’s test was used for statistical analysis of the data; the significance level was set at 5%. All systems prepared the comparable percentage of root canal surface with the similar magnitude of canal transportation in all root thirds (p > 0.05), but demonstrated significantly different resistance to cyclic fatigue (p < 0.05). The most resistant to fracture was EF, followed by EDM and CM. The length of the fractured fragments was not significantly different between the groups, and fractographic analysis by SEM detected the typical topographic features of separated thermally treated NiTi instrument surfaces.

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Cyclic fatigue resistance of 2Shape, Twisted File and EndoSequence Xpress nickel-titanium rotary files at intracanal temperature

Journal of Dental Research Dental Clinics Dental Prospects ◽

10.15171/joddd.2018.044 ◽

2018 ◽

Vol 12 (4) ◽

pp. 283-287 ◽

Cited By ~ 1

Author(s):

Gülşah Uslu ◽

Taha Özyürek ◽

Mustafa Gündoğar ◽

Koray Yılmaz

Keyword(s):

Fatigue Resistance ◽

Statistical Significance ◽

Cyclic Fatigue ◽

Nickel Titanium ◽

Bonferroni Correction ◽

Significant Difference ◽

Inner Diameter ◽

The Difference ◽

Number Of Cycles ◽

Analyze Data

Background. The aim of this study was to compare the cyclic fatigue resistance of 2Shape, Twisted File (TF) and EndoSequence Xpress (ESX) nickel-titanium rotary files at intracanal temperature (35°C). Methods. Twenty 2Shape TS1 (25/.04), 20 TF (25/.04) and 20 ESX (25/.04) files were tested for cyclic fatigue at intracanal temperature (35°C). All the instruments were rotated in artificial canals which were made of stainless steel with an inner diameter of 1.5 mm, 60° angle of curvature and a radius curvature of 5 mm until fracture occurred; the time to fracture was recorded in seconds using a digital chronometer and the number of cycles to fracture (NCF) for each file was calculated. Kruskal-Wallis test with Bonferroni correction was performed to statistically analyze data using SPSS 21.0. Statistical significance was set at P<0.05. Results. NCF values revealed that the 2Shape had significantly the highest cyclic fatigue resistance, followed by TF and ESX at intracanal temperature (P<0.05). The difference was significant between the TF and ESX groups (P<0.05). There was no significant difference among the 2Shape, TF and ESX files with respect to the lengths of the fractured file fragments (P>.05). Conclusion. Within the limitations of present study, it was concluded that the cyclic fatigue resistance of 2Shape files at the intracanal temperature is higher than that of TF and ESX files.

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