scholarly journals Mapping the Mechanical Properties of Hierarchical Supercrystalline Ceramic-Organic Nanocomposites

Molecules ◽  
2020 ◽  
Vol 25 (20) ◽  
pp. 4790 ◽  
Author(s):  
Büsra Bor ◽  
Lydia Heilmann ◽  
Berta Domènech ◽  
Michael Kampferbeck ◽  
Tobias Vossmeyer ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Organic Phase ◽  
Self Assembly ◽  
Organic Content ◽  
Treatment Temperature ◽  
Covalent Bonds ◽  
Soft Phase ◽  
Beneficial Effects ◽  
Ceramic Nanoparticles

Multiscale ceramic-organic supercrystalline nanocomposites with two levels of hierarchy have been developed via self-assembly with tailored content of the organic phase. These nanocomposites consist of organically functionalized ceramic nanoparticles forming supercrystalline micron-sized grains, which are in turn embedded in an organic-rich matrix. By applying an additional heat treatment step at mild temperatures (250–350 °C), the mechanical properties of the hierarchical nanocomposites are here enhanced. The heat treatment leads to partial removal and crosslinking of the organic phase, minimizing the volume occupied by the nanocomposites’ soft phase and triggering the formation of covalent bonds through the organic ligands interfacing the ceramic nanoparticles. Elastic modulus and hardness up to 45 and 2.5 GPa are attained, while the hierarchical microstructure is preserved. The presence of an organic phase between the supercrystalline grains provides a toughening effect, by curbing indentation-induced cracks. A mapping of the nanocomposites’ mechanical properties reveals the presence of multiple microstructural features and how they evolve with heat treatment temperature. A comparison with non-hierarchical, homogeneous supercrystalline nanocomposites with lower organic content confirms how the hierarchy-inducing organic excess results in toughening, while maintaining the beneficial effects of crosslinking on the materials’ stiffness and hardness.

scholarly journals Nanostructure, Self-Assembly, Mechanical Properties, and Antioxidant Activity of a Lupin-Derived Peptide Hydrogel

Biomedicines ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 294
Author(s):  
Raffaele Pugliese ◽  
Anna Arnoldi ◽  
Carmen Lammi
Keyword(s):  
Mechanical Properties ◽  
Antioxidant Activity ◽  
Self Assembly ◽  
Antioxidant Activities ◽  
Functional Materials ◽  
Cd Spectroscopy ◽  
Beneficial Effects ◽  
Naturally Occurring ◽  
New Research ◽  
Peptide Hydrogel

Naturally occurring food peptides are frequently used in the life sciences due to their beneficial effects through their impact on specific biochemical pathways. Furthermore, they are often leveraged for applications in areas as diverse as bioengineering, medicine, agriculture, and even fashion. However, progress toward understanding their self-assembling properties as functional materials are often hindered by their long aromatic and charged residue-enriched sequences encrypted in the parent protein sequence. In this study, we elucidate the nanostructure and the hierarchical self-assembly propensity of a lupin-derived peptide which belongs to the α-conglutin (11S globulin, legumin-like protein), with a straightforward N-terminal biotinylated oligoglycine tag-based methodology for controlling the nanostructures, biomechanics, and biological features. Extensive characterization was performed via Circular Dichroism (CD) spectroscopy, Fourier Transform Infrared spectroscopy (FT-IR), rheological measurements, and Atomic Force Microscopy (AFM) analyses. By using the biotin tag, we obtained a thixotropic lupin-derived peptide hydrogel (named BT13) with tunable mechanical properties (from 2 to 11 kPa), without impairing its spontaneous formation of β-sheet secondary structures. Lastly, we demonstrated that this hydrogel has antioxidant activity. Altogether, our findings address multiple challenges associated with the development of naturally occurring food peptide-based hydrogels, offering a new tool to both fine tune the mechanical properties and tailor the antioxidant activities, providing new research directions across food chemistry, biochemistry, and bioengineering.

Permanent Mold Casting Practice and Microstructure and Mechanical Properties of Thin-Sectioned ADI Casting

2007 ◽  
Vol 26-28 ◽  
pp. 531-534
Author(s):  
B.M. Moon ◽  
Bong Hwan Kim ◽  
Je Sik Shin ◽  
Sang Mok Lee
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Ductile Cast Iron ◽  
Treatment Temperature ◽  
Chemical Compositions ◽  
Permanent Mold ◽  
Permanent Mold Casting ◽  
Treatment Practice ◽  
Mold Casting ◽  
Si Content

For thin-walled casting development of austempered ductile iron (ADI), permanent mold casting and accompanied heat treatment practice were systematically investigated to suppress and/or remove chill defects of ductile cast iron (DCI) with various thickness of 2 to 9 mm and to ensure mechanical properties of the final ADI casting. Si content was increased up to 3.8% to reduce the chill formation tendency under a high cooling rate. The residual Mg content remarkably affected the nodule count, while the nodule size and spherodization were proven to have weak relationships. Austenitizing process followed by austempering was very sensitive to chemical compositions (Si and Sn) and heat treatment temperature. As a practical application, the steel bar coupler for a structural frame was tried to produce without subsequent machining.

The Change of Mechanical Properties for Anodic Aluminum Oxide by Heat Treatment

2006 ◽  
Vol 317-318 ◽  
pp. 323-326 ◽  
Author(s):  
D.J. Park ◽  
S.H. Kim ◽  
J.H. Lee ◽  
Seong Hee Lee ◽  
Yong Ho Choa
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Mechanical Property ◽  
Oxalic Acid ◽  
Aluminum Oxide ◽  
Crystalline Phase ◽  
Anodic Aluminum Oxide ◽  
Treatment Temperature ◽  
Microstructure Change ◽  
Anodic Aluminum

Anodic aluminum oxide (AAO) was prepared in three types of aqueous solutions with various applied voltage. The mechanical property of AAO prepared in different electrolyte was investigated and hardness was increased on account of the increase of the thickness between pores. The mechanical property and microstructure change of AAO prepared in oxalic acid at 40V was investigated by heat treatment. AAO prepared in oxalic acid at 40V was transformed from amorphous to crystalline phase by heat treatment above 800oC and hardness was increased about 2.6 times with increase of heat treatment temperature.

scholarly journals Self-Toughening and Self-Enhancement Poly(arylene ether nitrile) with Low Dielectric Constant by Solid Crosslinking Reaction

Polymers ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1403 ◽  
Author(s):  
Lifen Tong ◽  
Xiting Lei ◽  
Guangyao Yang ◽  
Xiaobo Liu
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Dielectric Constant ◽  
Thermal Properties ◽  
Heat Treatment Temperature ◽  
Treatment Temperature ◽  
Cross Linking ◽  
Hydroxyl Groups ◽  
Crosslinking Reaction ◽  
Arylene Ether

A novel poly(arylene ether nitrile) terminated with hydroxyl groups (PEN–OH) was synthesized successfully. The effects of heat-treatment temperature on the thermal properties, mechanical properties, and dielectric properties of the PEN–OH films were studied in detail. Due to the cross-linking reaction occurring, at high temperature, among the nitrile groups on the side of the PEN–OH main chain to form a structurally stable triazine ring, the structure of materials changes from a linear structure to a bulk structure. Thus, the thermal properties and mechanical properties were improved. In addition, the occurrence of cross-linking reactions can reduce the polar groups in the material, leading to the decrease of dielectric constant. As the heat-treatment temperature increased, the glass-transition temperature increased from 180.6 °C to 203.6 °C, and the dielectric constant decreased from 3.4 to 2.8 at 1 MHz. Proper temperature heat-treatment could improve the tensile strength, as well as the elongation, at the break of the PEN–OH films. Moreover, because of the excellent adhesive property of PEN–OH to copper foil, a double-layer flexible copper clad laminate (FCCL) without any adhesives based on PEN–OH was prepared by a simple hot-press method, which possessed high peel strength with 1.01 N/mm. Therefore, the PEN–OH has potential applications in the electronic field.

scholarly journals Pengaruh Perlakuan Temperatur dan Media Pendinginan Terhadap Sifat Ketangguhan Baja AISI 3215

Jurnal METTEK ◽  
2018 ◽  
Vol 4 (1) ◽  
pp. 23
Author(s):  
I Ketut Suarsana ◽  
IGN Nitya Santhiarsa ◽  
DNK Putra Negara
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Temperature Effect ◽  
Internal Stress ◽  
Treatment Temperature ◽  
Metal Heating ◽  
Quenching Medium ◽  
Quenching Media ◽  
Cooling Medium ◽  
Cooling Media

Perlakuan panas adalah pemanasan yang diikuti dengan penahanan dan pendinginan menggunakan media quenching. Pengerasan adalah pemanasan logam hingga suhu austenit, tahan pada suhu tersebut untuk sementara waktu dan kemudian didinginkan pada media pendinginan seperti air, minyak, udara, air garam. Untuk mengatasi perubahan sifat mekanik, perlu diberikan proses perlakuan panas. Hal ini perlu dilakukan untuk menghilangkan stress internal dan mencegah terjadinya retak atau cacat. Sifat mekanis ketangguhan adalah kemampuan material untuk menyerap energi sesaat sebelum terjadi fraktur pada struktur itu. Penelitian ini membahas tentang prediksi ketangguhan properti mekanik dengan memberikan pemanasan pada temperatur 800, 850 dan 9000C dan masing-masing specimen  diquenching dengan : air tawar, air laut dan minyak. Hasil penelitian menunjukkan bahwa terjadi peningkatan sifat ketangguhan dari efek temperatur dan media pendinginan yang digunakan. Data menunjukan pada 8000C dengan media quenching minyak nilai ketangguhan adalah 33,833 kg/cm2, serta suhu 9000C dengan quenching media air nilai ketangguhan adalah 40,8747 kg/cm2). Jadi semakin meningkat temperature perlakuan,  berpengaruh terhadap sifat ketangguhan impak bahan. Heat treatment is carried out by heating followed by anchoring and using quenching medium as cooling. Hardening is metal heating to austenite temperature, hold it at a temporary temperature and then cooled to cooling media such as water, oil, air, brine. To overcome the change of mechanical properties, need to be given process of heat treatment. This is to remove internal stress and prevent the occurrence of cracks or defects. The mechanical properties of toughness are the ability of the material to absorb energy without fracturing the structure. This study discusses the prediction of toughness of mechanical properties by heating at temperatures of 800, 850 and 9000C and each specimen quenching with: freshwater, seawater and oil. The results showed that there was an increase in the toughness properties of the temperature effect and the cooling medium used. The data show on 8000C with medium quenching oil the toughness value is 33.833 kg/cm2, and the temperature of 9000C with quenching medium water toughness value is 40.8747 kg/cm2). So the increasing of treatment temperature has influence to the material toughness

Prediction of Heating Processing-Properties of Ti2AlC/TiAl Compound Materials Based on BP Neural Network

2011 ◽  
Vol 306-307 ◽  
pp. 823-826
Author(s):  
Ming Wen ◽  
Yun Long Yue ◽  
Hai Tao Zhang ◽  
Yang Li
Keyword(s):  
Neural Network ◽  
Mechanical Properties ◽  
Heat Treatment ◽  
Bp Neural Network ◽  
Bending Strength ◽  
Treatment Temperature ◽  
Preparation Technology ◽  
Bp Artificial Neural Network ◽  
Processing Properties ◽  
Compound Materials

Parameters of processing (heat treatment temperature, holding time) and properties (Bending strength and Microhardness) of Ti2AlC/TiAl compound materials were obtained through mechanical properties examination, the network model was built by BP artificial neural network. The results show that the built model can reflect the relationships between processing and properties very well and has certain accuracy. It can be used for the prediction of the properties of Ti2AlC/TiAl compound materials after heating processing under different experiment conditions. Meanwhile, the model can also serve as a guide for the preparation technology of Ti2AlC/TiAl compound materials.

scholarly journals TO STUDY MECHANICAL PROPERTIES OF SPRING LIKE SPECIMEN BEFORE AND AFTER DIFFERENT HEAT TREATMENT OPERATIONS

2020 ◽  
Vol 6 (6) ◽  
pp. 1-8
Author(s):  
Amit Kumar
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Treatment Temperature ◽  
Muffle Furnace ◽  
Soaking Time ◽  
Standard Data ◽  
Treatment Processes ◽  
Specimen Material ◽  
Material Specimen ◽  
Before And After

In this work we have analyzed the effect heat treatment on properties of spring shape steel specimens under various heat treatment processes. Specimen was subjected to heat treatment in electric muffle furnace. Heat treatment temperature, soaking time and cooling rate were selected as per phase diagram of specimen material. Specimen was tested for mechanical properties before and after heat treatment. Two processes annealing and normalizing compared with respect to their effect on properties of spring shape specimens in reference with standard data for steel used.

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