High Strength Research Articles

The Chinese Knot inspired anisotropic TC4 lattice Structures: Ultra-high specific strength in engineering materials

Lattice structures possess high specific strength, multi-functionality through innovative structural designs. Here, we proposed an efficient method for the construction of lattice structures by elongating two-dimensional planar patterns along the load direction, which enabled the efficient utilization of 100 % materials for load bearing. Inspired by Chinese Knot (CK), a series of meticulously crafted TC4 lattice structures were fabricated by using selective laser melting. These structures feature nine tubular units arranged in a 3 × 3 matrix interconnected by sixteen parallel plates, and their failure modes were subsequently investigated by uniaxial compression tests. The results show that the specific compressive strength of the CK structure enhances as increasing the density. The detachment between the plate and tube, and the buckling of the plate, lead to the premature failure, which in turn leads to substantial variations in strength, estimated at approximately 80 MPa at ∼ 1.5 g/cm3. When the thickness of the plate exceeds 0.5 mm, and the tube wall thickness exceeds 0.04 mm, the CK structures show high stability and exhibit a 45° shear failure mode. Notably, the specific strength of the CK structure can surpass 330 MPa∙cm3/g, which represents the peak level of specific compressive strength compared to the current TC4 lattice structures.

Microstructure and mechanical property of CoCrFeNiAlxMn(1-x) dual-phase gradient high-entropy alloy coatings prepared by laser cladding

High-entropy alloy (HEAs), known for their balanced strength and ductility, are promising candidates for impact wear-resistant applications. In this study, CoCrFeNiAlxMn(1-x)(x = 0, 0.2, 0.8, 1.0) dual-phase gradient coatings with a layered structure were prepared using laser cladding technology to explore the microstructure evolution, tensile properties and fracture mechanism of gradient coating. As the Al content increased, the single-phase face-centered cubic (FCC) HEA coatings transitioned to dual-phase of FCC+ body-centered cubic (BCC) solid-solution, and finally to a single BCC phase. The remarkable improvement of microhardness is attributed to the dominance of the BCC phase and the impeding effect of the second phase particles on dislocation movement. The gradient coating exhibited a gradual change in internal element composition, microhardness, and structure along the depth direction, with the highest hardness value reaching 530 HV. Compared with the minimum tensile strength (69.03MPa) and the minimum elongation (0.14%) of single-layer coating, the gradient coatings exhibited a balance of high tensile strength and good plastic toughness, with a tensile strength of 597MPa and an elongation of 4.08%. Fracture analysis indicated a transition from ductile to brittle fracture in single-layer coatings as x values increased. The double-layer and four-layer gradient coatings displayed a mixed mode of brittle and plastic fracture. The study provides valuable insights into the design and fabrication of HEA gradient coatings, offering a novel approach to enhance the durability and performance of laser-clad coatings for various applications.

Magmatic and sedimentological arguments for an Ediacaran active margin in the Bayankhongor Zone in western Mongolia, Central Asian Orogenic Belt

Geochronological and geochemical investigation of the magmatic and sedimentary rocks from the south-eastern tip of the Bayankhongor Zone (central Mongolia) constrains the Neoproterozoic evolution of the northern margin of the Baidrag Block. There, ultramafic to felsic igneous rocks of the Khan-Uul Massif intruded the volcano-sedimentary sequence of the Ulziit Gol Unit. U–Pb zircon ages show that both the plutonic and volcanic rocks were coeval products of the same Ediacaran (598–564 Ma) magmatism. Most of the samples have low contents of high field strength elements typical of arc-related magmas; however, some mafic rock samples display N-MORB-like chemistry. Magmatic rocks in the Khan-Uul Massif and Ulziit Gol Unit yielded exclusively positive initial εHf in zircon values (+4.9 to +13.8), implying derivation from depleted-mantle sources. Furthermore, heterogeneity of the whole-rock initial εNd values (–4.0 to +2.1) documents that fractional crystallization was accompanied by variable crustal contamination. The detrital zircon age patterns of the sandstone and tuffites in the Ulziit Gol Unit indicate that the sequence was filled dominantly by Ediacaran magmatic detritus derived from the Khan-Uul Massif and its volcanic equivalents, while the older cratonic material from the Baidrag basement represented only a subordinate component. Combined magmatic and sedimentary records imply that both the Khan-Uul Massif and the Ulziit Gol Unit may have formed in the same back-arc basin environment. This challenges the previous view that the entire Bayankhongor Zone was ophiolitic in nature. Distribution of coeval Ediacaran supra-subduction systems on the scale of the Mongolian Collage indicates the closure of multiple oceanic basins rimming the Siberian Continent. Following Rodinia break-up, this peri-Siberian realm was presumably formed by sub-parallel continental ribbons and oceanic basins. It is proposed that the amalgamation of these blocks and closure of intervening oceans reflected the Ediacaran advancing mode of the Palaeo-Pacific subduction.

Strengthening mechanism of large-diameter magnetic particles on ferrofluid nanoparticle chaining

The magnetization of nano ferrofluid is lower than that of micrometer magnetorheological fluid, which limits its application in seals, dampers, and various other fields. To enhance the ferrofluid performance, this paper incorporates large-diameter magnetic particles into the ferrofluid to strengthen chaining among nanoparticles. A matrix discrete element method model is constructed to investigate the strengthening mechanism of large-diameter magnetic particles on ferrofluid nanoparticle chaining. Additionally, the chain formation process involving both large and small particles and the influence of large particle volume fractions on chain length, particle number, and yield strength are studied based on the simulation. The results show that small particles and large particles together constitute different complex structures, such as the columnar structure and column-net structure under the strong magnetic dipole force of the large particles, leading to the high chain structure strength. In addition, the chain formation speed, average chain length, average particle number, yield strength, and additional viscosity are influenced by the volume fractions and particle sizes of large particles. The method will enhance the ferrofluid sealing performance and expand the ferrofluid application areas.

Reflectivity measurement of a silicon carbide mirror sample for ITER divertor vacuum ultraviolet spectrometer.

The first mirror is the front-end optic component that reflects light emitted from the plasma to the diagnostic system in fusion plasmas. Silicon carbide (SiC), known for its relatively high mechanical strength and radiation tolerance, has been selected as the substrate material for the first mirror in the ITER divertor vacuum ultraviolet (VUV) spectrometer. To measure the reflectivity of the ellipse cylindrical SiC mirror to be manufactured, a device for reflectivity measurement in the VUV wavelength range was developed. First, the reflectivity of a sample SiC mirror (15mm diameter × 10mm thick) was measured across the ITER-required incidence angles, and the results are reported in this study. A hollow cathode lamp with helium gas was used as the VUV light source in the wavelength range of 23-60nm, and a dedicated VUV spectrometer to select specific wavelengths was developed. The spectrometer utilized laminar-type replica diffraction gratings (Shimadzu 30-006) and two back-illuminated charge-coupled devices (BI-CCD, Andor DO 940P-BEN) for the grating and detector, respectively. A cropping technique with aperture was employed to precisely localize the VUV light's reflection onto the SiC mirror surface. The experimentally measured reflectivity values of SiC at the required incidence angles of VUV light were compared with theoretically calculated reflectivity curves. The oxidation layer (SiO2) formed on the SiC surface and the incidence angle of VUV light to the BI-CCD chip (E2V) would be the factors affecting the accuracy of the reflectivity.

Study on the effect of Sc and Zr addition on microstructure, mechanical property and fracture behavior of electron beam welded Be-Al alloys

Because of various excellent properties of low density, high specific strength and stiffness, high modulus, good thermal stability and corrosion-resistant, beryllium-aluminum (Be-Al) alloys have shown great potential to be used in nuclear industries. However, Be-Al alloys suffer from the bottlenecks of low solubility between Be and Al and the lack of effective technology for fabricating large-sized products. Herein, based on Sc and Zr addition, Be-Al-Sc-Zr alloys are successfully fabricated by conducting the electron beam welding (EBW) technology, and the effect of Sc and Zr addition on microstructure, mechanical property and fracture behavior of Be-Al-Sc-Zr alloys is studied. Microstructural characterizations show that both the EBWed Be-Al and Be-Al-Sc-Zr alloys exhibit two distinct zones of substrate zone (SZ) and fusion zone (FZ). Compared to grain size of the SZ and FZ in Be-Al alloys, grain sizes of these two zones in Be-Al-Sc-Zr alloys are significantly refined, thus leading to ultimate tensile strength (UTS) of the Be-Al-Sc-Zr alloys (~176MPa) approximately 150% higher than that of the Be-Al alloys (~118MPa). Besides, a newly generated third phase (TP), which is confirmed as Be13(Scx, Zr1-x), forms within Al phase in both SZ and FZ of the Be-Al-Sc-Zr alloys. Different from fracture behavior of Be-Al alloys that preferentially fractures within Al phase or near the Be/Al interface, fracture of the Be-Al-Sc-Zr alloys is prone to occur within Be phase. As revealed by the calculation results of finite element method (FEM), the underlying mechanism for different fracture behaviors mainly ascribes to that the reinforcement of the Al phase and the existence of the newly formed TP can greatly increases the internal stress and even causes stress concentration within Be phase of the Be-Al-Sc-Zr alloys. The present findings may provide more insights to the micro-alloying and deformation mechanism of Be-Al alloys that with enhanced mechanical properties.

Nanofibrous Membranes with High Mechanical Strength for the Separation and Purification of Lysozyme

Nanofibrous Membranes with High Mechanical Strength for the Separation and Purification of Lysozyme

Creation of a nickel composite using surface structuring of the reinforcing phase with titanium carbide nanostructures to improve strength properties

Abstract The development of metal matrix composite (MMC) materials is one of the demanded areas of research in materials science. In line with this trend, there is an increasing interest in nickel-based MMC materials, which have already become classic in science and technology. This is due to the high demand for Ni-based materials with high strength characteristics, high hardness, and increased heat resistance. In this research, we proposed an approach to obtain a MMC material using the surface structuring process, ALD (Atomic Layer Deposition) and powder metallurgy method. The developed approach provides a composite with TiC nanostructures (1-5 nm) uniformly distributed throughout the Ni matrix. The absence of interphase boundaries between the Ni matrix particles and carbide nanostructures made it possible to minimize the internal porosity of the sample. This is due to the strength of the interphase boundaries between the matrix and the reinforcing phase in the composite and to the solidity of the structure. As a result, the created material effectively resists plastic deformation and stress. This allows not only to enhance the strength properties of the composite, but also to maintain the MMC plasticity, which increases its processing ability.

Effect of N on microstructure, nucleation mechanism and mechanical performance of (Ti, Nb) C particles in Fe-based composite coating via plasma spray welding

Compared with the coating of Ti-Nb-C system, the coating of Ti-Nb-C-N system shows better mechanical properties, especially wear resistance. Therefore, this investigation was focus on the in-situ (Ti, Nb) C reinforced Fe-based composite coatings (D1 composite coatings) and in-situ (Ti, Nb) (C, N) reinforced Fe-based composite coatings (D2 composite coatings) which were created on high strength steel via plasma spray welding (PSW) technology in the environment with nitrogen and without nitrogen, respectively. The two coatings were compared to explore nucleation mechanism of nitrogen on (Ti, Nb) C particles, grain size, particle morphology and the influence on the mechanical performance of coatings. The findings showed that the changes in the typical microstructure morphology and the shape of the reinforced particles of the two coatings were not obvious. However, the heterogeneous nucleation sites of (Ti, Nb) C were provided by introducing nitrogen. In addition, the introduction of nitrogen could refine the grains of D1 composite coatings. As a result, the average grain size of D1 composite coatings decreased by an order of magnitude, and the crystal orientation of the grains in the composite coatings showed better isotropy. The average microhardness of D2 composite coatings was 967.52 HV1, which was 1.5 times of the average microhardness of D1 composite coatings. The wear loss of D2 composite coatings was 0.4 mg, which was only half of that of D1 composite coatings (0.8 mg).

Ablation and mechanical behavior of reusable Cf/SiC-ZrC with a gradient-structured matrix produced by reactive melt infiltration

Cf/SiC-ZrC renowned for its outstanding performance as a thermal protectant, has gaining widespread recognition. Recent research on this system has emphasized the development of a cost-effective and reusable version with increased thickness for extended use in thick-walled thermal structural components. Ablation resistance, high strength retention, and high thermal conductivity are crucial for successful aircraft reentry. In this study, a low-cost reactive melt infiltration (RMI) method is developed for preparing dense and high-performance large-thickness Cf/SiC-ZrC (L-Cf/SiC-ZrC) with a gradient-structured matrix. The use of a fine weave-pierced fabric preform structure enhances both the structural integrity and thermal conductivity of Cf/SiC-ZrC in the thickness direction. Simultaneously, the gradient-structured matrix, with appropriate contents of surficial ZrC and SiC exhibits erosion resistance, where the internal core with a high SiC content ensures remarkable strength retention. This unique matrix-structure design is achieved by integrating porous C with a single-stage pore structure and a high degree of graphitization degree, and a Si-Zr alloy with a unique composition. The 20mm thick Cf/SiC-ZrC obtained via RMI has a density of 2.79 g/cm3 with an open porosity of 5.65% and flexural strength of 224.3±5.4 MPa. Under a heat flux of 4.186 MW/m2, Cf/SiC-ZrC exhibits an ablation rate of −0.004 mm/s after 60 s, demonstrating its resilience against ablation damage. Moreover, the post-ablation strength (166.0±4.4 MPa) exceeds that of reported Cf/SiC-ZrC congeners, highlighting the robust load-bearing capability.

Polydopamine-induced biomimetic mineralization strategy to generate hydroxyapatite for the preparation of carbon fiber composites with excellent mechanical properties

Living organisms have developed a miraculous biomineralization strategy to form multistage organic-inorganic composites through the orderly assembly of hard/soft substances, achieving mechanical enhancement of materials from the nanoscale to the macroscale. Inspired by biominerals, this study used polydopamine (PDA) coating as a template to induce the growth of hydroxyapatite (HAP) on the surface of carbon fibers (CFs) for enhancing the interfacial properties of the CF/epoxy resin composites. This polydopamine-assisted hydroxyapatite formation (pHAF) biomimetic mineralization strategy constructs soft/hard ordered structure on the CF surface, which not only improves the chemical reaction activity of the CFs but also increases the fiber surface roughness. This, in turn, enhances the interaction and loading delivery among the fibers and the matrix. Compared to the untreated carbon fiber/epoxy resin (CF/EP) composites, the prepared composites showed a substantial enhancement in interlaminar shear strength (ILSS), flexural strength, and interfacial shear strength (IFSS), with improvements of 45.2 %, 46.9 %, and 60.5 %, respectively. This can be attributed to the HAP nanolayers increasing the adhesion and mechanical interlocking with the CFs to the matrix. This study provides an interface modification method of biomimetic mineralization for the preparation of high strength CF composites.

Relationship between microstructure and mechanical properties of V-N microalloyed high strength ship plate steel

V-N microalloying treatment is an important way to improve the service performance of non-quenched and tempered ship plate steel. Herein, the influence of V(C, N) on the evolution of microstructure and improvement of mechanical properties was studied. In addition, the relationship between microstructure and mechanical properties of V-N microalloyed high strength ship plate steel was revealed. The results showed that the composite addition of V and N not only formed a fine dispersed precipitated phase, but more importantly, significantly refined the ferrite/pearlite microstructure, promoted the formation of intragranular acicular ferrite, increased the proportion of high angle grain boundaries, and decreased the kernel average misorientation value. The optimization of microstructure brought about by V-N microalloying achieved synchronous improvement of strength and cryogenic toughness. The impact energy of V-N microalloying ship plate steel increased from 97 J of V-N-free ship plate steel to 239 J at −40 °C, and the impact fracture mode changed from brittle quasi-cleavage fracture to microvoid coalescence fracture with a large number of equiaxial dimples.

Bone healing under different lay-up configuration of carbon fiber-reinforced PEEK composite plates.

Secondary healing of fractured bones requires an application of an appropriate fixator. In general, steel or titanium devices are used mostly. However, in recent years, composite structures arise as an attractive alternative due to high strength to weight ratio and other advantages like, for example, radiolucency. According to Food and Drug Administration (FDA), the only unidirectionally reinforced composite allowed to be implanted in human bodies is carbon fiber (CF)-reinforced poly-ether-ether-ketone (PEEK). In this work, the healing process of long bone assembled with CF/PEEK plates with cross- and angle-ply lay-up configurations is studied in the framework of finite element method. The healing is simulated by making use of the mechanoregulation model basing on the Prendergast theory. Cells transformation is determined by the octahedral shear strain and interstitial fluid velocity. The process runs iteratively assuming single load cycle each day. The fracture is subjected to axial and transverse forces. In the computations, the Abaqus program is used. It is shown that the angle-ply lamination scheme of CF/PEEK composite seems to provide better conditions for the transformation of the soft callus into the bone tissue.

Mechanical behavior of GFRP-Polymer sandwich composites with montmorillonite nanoclay

Abstract A sandwich composite consists of high stiffness and high strength outer layers called face sheets and low-density inner layers called core. In the present study, the sandwich composites comprising glass fabric/epoxy face sheets and epoxy modified with montmorillonite (MMT) nanoclay core are fabricated by a co-curing method. The sandwich panels show higher static tensile and three-point flexural properties such as ultimate strength, elastic modulus, and failure strain on adding up to 3 wt.% of MMT nanoclay contents than pristine sample. The former properties reduce at 4 and 5 wt.% of nanoclay contents owing to the formation of clustering of clay particles within the matrix. The stress-strain behavior of sandwich panels with 0–5 wt.% of MMT nanoclays obtained by laminated plate model follows experiments. The maximum lateral deflection of sandwich panels with nanoclays predicted by assuming them to be a simply supported beam is in-line with experimental results. For low-velocity single impact perforation load, the maximum force of sandwich panels improves on the infusion of up to 3 wt.% of clay while maximum displacement decreases. The ballistic limit velocity and energy absorption of panels improve on adding up to 3 wt.% of clay. Beyond the ballistic limit at different initial velocities, the residual velocity of sandwich panels decreases on addition of up to 3 wt.% of clay and energy absorption increases.

Enhancement mechanisms of mechanical, electrical and thermal properties of carbon nanotube-copper composites: A review

Carbon nanotubes (CNTs), as potent reinforcements in composites, have demonstrated excellent strengthening effects when combined with copper in numerous recent studies. Challenges remain in the application of these composites and in fully leveraging the reinforcing capabilities of CNTs to achieve comprehensive performance enhancement. The performance of CNTs/Cu composites can be flexibly regulated owing to the unique structure and properties of CNTs. To achieve the fabrication of high-performance and diverse CNTs/Cu composites, a profound understanding of the reinforcement mechanisms of CNTs in the composites is essential, along with the consideration of key influencing factors on performance. This article provides a comprehensive overview of the reinforcement mechanisms of CNTs on the mechanical, electrical, and thermal properties of CNTs/Cu composites. Factors influencing the effectiveness of CNT reinforcement in composites are discussed, including the attributes and dispersion of CNTs, the architectures of composites, and the interface between CNTs and Cu. Furthermore, this study explores the role of CNTs in addressing the trade-off between high strength and high conductivity as well as between high strength and high ductility in the copper matrix.

Advancements in Coordination Chemistry and Trends in the Chemical Industry: Applications and Implications

Abstract: Metal foams offer a compelling combination of properties, including low density, sound absorption, high compressive strength, and stiffness. This project focuses on the damping behavior of aluminum foams for applications in automobiles and various industries. Aluminum foams excel in being lightweight, exhibiting high compressive strength, and offering excellent stiffness. However, their wear resistance is a limitation. To address this and enhance durability, a diamond-like carbon (DLC) coating is applied to the surface. The complex geometry and surface of aluminum foams pose a challenge for the coating process. Therefore, the project employs the well-established cataphoretic deposition technique, an electro-chemical process. This research investigates the potential of carbon-coated aluminum foam for vibration mitigation in automobiles and industrial applications by analyzing its damping properties and improved wear resistance through the DLC coating

Simultaneously Strengthening and Toughening All‐Natural Structural Materials via 3D Nanofiber Network Interfacial Design

AbstractConstructing structural materials from sustainable raw materials is considered an efficient way to reduce the potential threat posed by plastics. Nevertheless, challenges remain regarding combining excellent mechanical and thermal properties, especially the balance of strength and toughness. Here, we report a 3D nanofiber network interfacial design strategy to strengthen and toughen all‐natural structural materials simultaneously. The introduced protonated chitosan at the interface between the surface oxidized 3D nanonetwork of bacterial cellulose forms the interfacial interlocking structure of nanonetworks, achieving a robust physical connection and providing enough physical contact sites for chemical crosslinking. The obtained sustainable structural material successfully integrates excellent mechanical and thermal properties on the nanoscale of cellulose nanofibers, such as light weight, high strength, and superior thermal expansion coefficient. The relationship between structural design and comprehensive mechanical property improvement is analyzed in detail, providing a universal perspective to design sustainable high‐performance structural materials from nanoscale building blocks.

Mechanically Robust Biopolymer Optical Fibers with Enhanced Performance in the Near-Infrared Region.

Polymer optical fibers (POFs) are lightweight, fatigue-tolerant, and suitable for local area networks, automobiles, aerospace, smart textiles, supercomputers, and servers. However, commercially available POFs are exclusively fabricated using synthetic polymers derived from nonrenewable resources. Recently, attempts have been made to fabricate biocompatible and biopolymeric optical fibers. However, their limitations in mechanical performance, thermal stability, and optical properties foil practical applications in waveguiding. Here, we report a comprehensive study of the preparation of biopolymer optical fibers with tailored mechanical strength, thermal properties, and their short-distance applications. Specifically, we use alginate as one of the key components with methylcelluloses to promote readily scalable wet spinning at ambient conditions to fabricate 21 combinations of composite fibers. The fibers display high maximum strain (up to 58%), Young's modulus (up to 11 GPa), modulus of toughness (up to 63 MJ/m3), and a high strength (up to 195 MPa), depending on the composition and fabrication conditions. The modulus of toughness is comparable to that of glass optical fibers, while the maximum strain is nearly 15 times higher. The mechanically robust fibers with high thermal stability allow rapid humidity, touch sensing, and complex shapes such as serpentine, coil, or twisted structures without losing their light transmission properties. More importantly, the fibers display enhanced optical performance and sensitivity in the near-infrared (NIR) region, making them suitable for advanced biomedical applications. Our work suggests that biobased materials offer innovative solutions to create short-distance optical fibers from fossil fuel-free resources with novel functionalities.

Study of electronic properties, mechanical properties and corrosion properties of trace Ce added to Al–Si–Mg–Cu alloys

Corrosion and deformation are one of the main causes of material failure in aluminum alloys, which increases the probability of accidents and causes huge economic losses. In this paper, the mechanism of modification of Al–Si–Mg–Cu alloy by Ce addition was investigated. The effects of common elements in aluminum alloys on Ce solid solution were calculated, in which the ability to promote Ce solid solution in Al was in the following order: Cu＞Mg＞Fe＞Ti＞O＞Si. The changes in the properties of the experimental alloys with different Ce contents were investigated by nanoindentation, tensile test and electrochemistry. The results show that the addition of Ce effectively improves the corrosion resistance and strength of the extruded Al–Si–Mg–Cu alloy. However, the addition of excess Ce decreases the corrosion resistance of the alloy, which was highest with the addition of 0.4 wt% Ce. The Ecorr value is shifted in a positive direction, increasing from the standard electrode potential of Al (−1.66 V) to −0.997 V. In addition, the growth of tensile strength and yield strength becomes slow when the Ce addition exceeds 0.4 %. The results provide technical guidance for the development of new aluminum alloy materials with high corrosion resistance, high strength, and low cost.

Simultaneously Strengthening and Toughening All-Natural Structural Materials via 3D Nanofiber Network Interfacial Design.

Constructing structural materials from sustainable raw materials is considered an efficient way to reduce the potential threat posed by plastics. Nevertheless, challenges remain regarding combining excellent mechanical and thermal properties, especially the balance of strength and toughness. Here, we report a 3D nanofiber network interfacial design strategy to strengthen and toughen all-natural structural materials simultaneously. The introduced protonated chitosan at the interface between the surface oxidized 3D nanonetwork of bacterial cellulose forms the interfacial interlocking structure of nanonetworks, achieving a robust physical connection and providing enough physical contact sites for chemical crosslinking. The obtained sustainable structural material successfully integrates excellent mechanical and thermal properties on the nanoscale of cellulose nanofibers, such as light weight, high strength, and superior thermal expansion coefficient. The relationship between structural design and comprehensive mechanical property improvement is analyzed in detail, providing a universal perspective to design sustainable high-performance structural materials from nanoscale building blocks.