High Mechanical Hardness Research Articles

Ultra-precision diamond finishing of reaction-sintered silicon carbide enhanced by vibration-assisted photocatalytic oxidation

RS-SiC faces limitations in surface accuracy with conventional finishing processes due to its high mechanical hardness and multiphase nature. In this study, vibration-assisted photocatalytic oxidation is introduced to enhance the efficiency and precision of RS-SiC diamond polishing. By utilizing the photocatalytic reaction, the hard heterogeneous SiC phase and Si phase on the RS-SiC surface are transformed into a "softer" homogeneous oxide layer that can be removed easily. The introduction of vibration increases the relative velocity between the workpiece and the abrasive and prevents the aggregation of the photocatalyst, thus improving polishing efficiency. By reducing the abrasive size to the nanometer scale, the boundary between the Si phase and SiC phase can be smoothed out to further improve the workpiece surface finish. Using TiO2 as the photocatalyst, H2O2 as the oxidant, 25 nm diamond as the abrasive, and introducing vibration, an ultra-smooth surface with a surface roughness of 0.195 nm in Ra is obtained by the finishing method proposed in this paper. The proposed photocatalysis/vibration-assisted finishing approach offers a novel method for ultra-smooth polishing reaction-sintered silicon carbide.

In situ monitoring of sapphire nanostructure etching using optical emission spectroscopy

Fabrication of nanostructures on sapphire surfaces can enable unique applications in nanophotonics, optoelectronics, and functional transparent ceramics. However, the high chemical stability and mechanical hardness of sapphire make the fabrication of high density, high aspect ratio structures in sapphire challenging. In this study, we propose the use of optical emission spectroscopy (OES) to investigate the sapphire etching mechanism and for endpoint detection. The proposed process employs nanopillars composed of polymer and polysilicon as an etch mask, which allows the fabrication of large-area sapphire nanostructures. The results show that one can identify the emission wavelengths of key elements Al, O, Br, Cl, and H using squared loadings of the primary principal component obtained from principal component analysis of OES readings without the need of domain knowledge or user experience. By further examining the OES signal of Al and O at 395.6 nm, an empirical first-order model can be used to find a predicted endpoint at around 170 s, indicating the moment when the mask is completely removed, and the sapphire substrate is fully exposed. The fabrication results show that the highest aspect ratio of sapphire nanostructures that can be achieved is 2.07, with a width of 242 nm and a height of 500 nm. The demonstrated fabrication approach can create high sapphire nanostructures without using a metal mask to enhance the sapphire etch selectivity.

Hyaluronic acid-British anti-Lewisite as a safer chelation therapy for the treatment of arthroplasty-related metallosis.

Cobalt-containing alloys are useful for orthopedic applications due to their low volumetric wear rates, corrosion resistance, high mechanical strength, hardness, and fatigue resistance. Unfortunately, these prosthetics release significant levels of cobalt ions, which was only discovered after their widespread implantation into patients requiring hip replacements. These cobalt ions can result in local toxic effects-including peri-implant toxicity, aseptic loosening, and pseudotumor-as well as systemic toxic effects-including neurological, cardiovascular, and endocrine disorders. Failing metal-on-metal (MoM) implants usually necessitate painful, risky, and costly revision surgeries. To treat metallosis arising from failing MoM implants, a synovial fluid-mimicking chelator was designed to remove these metal ions. Hyaluronic acid (HA), the major chemical component of synovial fluid, was functionalized with British anti-Lewisite (BAL) to create a chelator (BAL-HA). BAL-HA effectively binds cobalt and rescues in vitro cell vitality (up to 370% of cells exposed to IC50 levels of cobalt) and enhances the rate of clearance of cobalt in vivo (t1/2 from 48 h to 6 h). A metallosis model was also created to investigate our therapy. Results demonstrate that BAL-HA chelator system is biocompatible and capable of capturing significant amounts of cobalt ions from the hip joint within 30 min, with no risk of kidney failure. This chelation therapy has the potential to mitigate cobalt toxicity from failing MoM implants through noninvasive injections into the joint.

Self-fluxing amorphous Nickel-based alloys obtained by different techniques. Performance and technological difficulties

Amorphous metal alloys can already be considered advanced structural materials. This structure induces specific properties such as: high mechanical resistance and hardness, high bending ductility, high elastic modulus, superior resistance to corrosion and wear or, depending on the chemical composition, exceptional magnetic properties. The family of self-fluxing alloys based on nickel has multiple applications: NiCrBSi powders are used with remarkable results in obtaining protective layers against corrosion and wear, strips and wires are successfully used as brazing alloys, etc. In this paper it is presented the research carried out for obtaining and characterizing the amorphous NiCrSiB ribbons, through the melt spinning technique and the massive products (bulks) from the same family through mold casting and additive manufacturing using the Selective Laser Melting (SLM) technique

Anti-corrosion and erosion properties of multilayers with diamond-like carbon and silicon films deposited on low-carbon steel

A multilayer of diamond-like carbon (DLC) and silicon (Si) films were deposited on low-carbon steel (CS) using a combination of bipolar-pulsed magnetron sputtering (MS) and the radio frequency plasma enhanced chemical deposition (RF-PECVD) methods. Spectroscopic techniques such as Raman spectroscopy, synchrotron-based X-ray photoemission spectroscopy (XPS), and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy were used to investigate the chemical and structural properties of the film. The mechanical properties were measured using nanoindentation and nano-scratch testers. The films' electrochemical performance and corrosion behavior were evaluated in the 3.5 wt% NaCl solution at room temperature. The erosion resistance of the films was studied under the sand jet impingement apparatus. The results indicate that the 2 Si-layers in the DLC film and CS substrate increase the C‒sp3 content at the DLC film surface resulting in high mechanical hardness. The adhesion of the DLC film on the CS substrate was also improved by adding the Si layer between the CS substrate and DLC film. Consequently, multilayer Si/DLC film resists the elastic deformation of films caused by graphitization.

DFT study of electronic, optical, and elastic properties of double perovskites Rb2YAgX6 (X = Br, I) compounds for opto-electronic device applications

Density functional theory calculations have been used to investigate the electrical, optical, and elastic characteristics of double perovskites Rb2YAgX6 (X = Br, I) halides for exploring their opto-electronic applications. For optimizing the lattice constants and structure parameters, we have fitted the Murnaghan equation of state to the total energies computed for a wide range of lattice volumes. For the ground state lattice constants, the computed electronic band structure diagrams show indirect wide band gaps of 4.2 eV and 3.2 eV for Rb2YAgBr6 and Rb2YAgI6, respectively. Our results indicate that both of the studied halides absorb electromagnetic radiations beyond the visible region and are therefore appear potential candidates for optoelectronic applications in the ultraviolet rage of spectrum. The mechanical stability and ductility of the two halides are examined in terms of the elastic constants. Our results clearly demonstrate that the device application potential of these double perovskite halides is interesting owing to their high mechanical stability and hardness.

Recent Progress of Nanodiamond Film in Controllable Fabrication and Field Emission Properties.

The interest in the field electron emission cathode nanomaterials is on the rise due to the wide applications, such as electron sources, miniature X-ray devices, display materials, etc. In particular, nanodiamond (ND) film is regarded as an ideal next-generation cathode emitter in the field emission devices, due to the low or negative electron affinity, small grain size, high mechanical hardness, low work function, and high reliability. Increasing efforts are conducted on the investigation of the emission structures, manufacturing cost, and field emission properties improvement of the ND films. This review aims to summarize the recent research, highlight the new findings, and provide a roadmap for future developments in the area of ND film electron field emitter. Specially, the optimizing methods of large-scale, high-quality, and cost-effective synthesis of ND films are discussed to achieve more stable surface structure and optimal physical properties. Additionally, the mainstream strategies applied to produce high field emission performance of ND films are analyzed in detail, including regulating the grain size/boundary, hybrid phase carbon content, and doping element/type of ND films; meanwhile, the problems existing in the related research and the outlook in this area are also discussed.

Nanoreactors in action for a durable microactuator using spontaneous combustion of gases in nanobubbles

A number of recent studies report enhancement of chemical reactions on water microdroplets or inside nanobubbles in water. This finding promises exciting applications, although the mechanism of the reaction acceleration is still not clear. Specifically, the spontaneous combustion of hydrogen and oxygen in nanobubbles opens the way to fabricate truly microscopic engines. An example is an electrochemical membrane actuator with all three dimensions in the micrometer range. The actuator is driven by short voltage pulses of alternating polarity, which generate only nanobubbles. The device operation is, however, restricted by a fast degradation of the electrodes related to a high current density. Here it is demonstrated that the actuator with ruthenium electrodes does not show signs of degradation in the long-term operation. It is the only material able to withstand the extreme conditions of the alternating polarity electrolysis. This property is due to combination of a high mechanical hardness and metallic conductivity of ruthenium oxide. The actuator combines two features considered impossible: on-water catalysis and combustion in a microscopic volume. It provides an exceptional opportunity to drive autonomous microdevices especially for medical or biological applications.

Enhanced mechanical and biocompatibility performance of Ti(1-)Ag(x) coatings through intermetallic phase modification

Advanced materials combining superior mechanical and biocompatibility performance are of significant interest to extend the lifetime of biomedical devices. In this work, Ag is alloyed with Ti to investigate the role of emerging Ti Ag intermetallic coatings with high mechanical hardness and exceptional biocompatibility. Thin films of Ti (1- x ) Ag (x) were deposited on 316 L steel and glass substrates using magnetron sputtering and subsequently heat-treated to aid Ti Ag intermetallic development. Mechanical properties were then measured and correlated to microstructural and morphological changes in the Ti Ag films. In the as-grown state, the Ti Ag matrix developed different intermetallic structures which increased the hardness of pure Ti films from 5 to >7 GPa. After heat treatment, a peak hardness of 7.39 GPa and elastic modulus of 105 GPa was achieved for a 43 at.% Ag film due to formation of the tetragonal Ti Ag phase and increase of upper surface oxides which act as dislocation barriers. However, at higher Ag concentrations, heat treatment leads to agglomeration of Ag around grain boundaries and decreases the crystallite size, leading to reduction in hardness to <3 GPa. The Ti rich films also depict better cytotoxicity performance following exposure to the L929 cell line, though excellent cell viability values >98% are observed for the entire Ti Ag range. While leached ion concentrations lower than 100 ppb demonstrate excellent biocompatibility of this Ti Ag alloy system. This work demonstrates the first successful attempt to develop biocompatible Ti Ag thin film coatings with high mechanical hardness with the potential to extend the lifetime of medical implants. • First study on biomechanical performance of Ti (1-x) -Ag (x) intermetallic films. • First report on external heat treatment to develop Ti Ag intermetallic thin films. • Ag addition causes transition to tetragonal Ti Ag structure with enhanced hardness. • Heat treatment leads to improved crystallinity and mechanical performance. • Ti Ag films exhibit excellent biocompatibility before and after heat treatment.

Mechanical property and irradiation resistance of high entropy pyrochlore (Sm0.2Eu0.2Gd0.2Y0.2Lu0.2)2Ti2O7

High entropy ceramics have recently attracted a lot of attention due to their superior physical properties. In this work, a novel high entropy pyrochlore (Lu0.2Y0.2Gd0.2Eu0.2Sm0.2)2Ti2O7 (HTP-1) was designed and prepared. Sample was characterized by X-ray diffraction, Raman spectroscopy and transmission electron microscopy coupled with an energy dispersive spectrometry. The results show that single-phase HTP-1 is successfully synthesized and exhibits severe lattice distortion. The Vickers hardness of HTP-1 measured by the microhardness tester is ∼ 922.28 Hv, which is significantly higher than the result calculated with the mixture rule, demonstrating that high entropy pyrochlore has high mechanical hardness. In-situ TEM was performed on HTP-1 irradiated with 800 keV Kr2+ at room temperature to investigate irradiation resistance of sample. The critical amorphization dose of HTP-1 is 0.27 dpa, which indicates the irradiation resistance of HTP-1 is between Sm2Ti2O7 and Y2Ti2O7.

Experimental study of the structural, magnetic, electrical, and mechanical properties of possible half-metallic Co[formula omitted]V[formula omitted]FeGe Heusler alloys

In this study, we experimentally investigated quaternary Heusler alloys Co2−xVxFeGe with 0≤x≤1 prepared by arc melting and annealing, and showed that they are promising candidates for spintronics applications. Single phase microstructures were observed for V compositions from x=0.25 to x=0.625. Other V concentrations were multi-phased. All single phase samples had a face centered cubic crystal structure with a lattice constant that increased linearly with the V concentration. The low-temperature saturation magnetic moments were shown to obey the Slater–Pauling rule of thumb for half-metals, which is a prerequisite for half metallicity. All alloys had high Curie temperatures, which scaled linearly with the saturation magnetic moment, thereby facilitating applications at room temperature and above. Electrical transport measurements were performed to elucidate the electronic structures of the alloys. The temperature dependence of the electrical resistivity was analyzed and discussed in the framework of the two-current conduction model by considering the existence of an energy gap in the electronic spectrum around the Fermi level of the spin down sub-band. High mechanical hardness values were also observed.

3D Printing of Bioinert Oxide Ceramics for Medical Applications.

Three-dimensionally printed metals and polymers have been widely used and studied in medical applications, yet ceramics also require attention. Ceramics are versatile materials thanks to their excellent properties including high mechanical properties and hardness, good thermal and chemical behavior, and appropriate, electrical, and magnetic properties, as well as good biocompatibility. Manufacturing complex ceramic structures employing conventional methods, such as ceramic injection molding, die pressing or machining is extremely challenging. Thus, 3D printing breaks in as an appropriate solution for complex shapes. Amongst the different ceramics, bioinert ceramics appear to be promising because of their physical properties, which, for example, are similar to those of a replaced tissue, with minimal toxic response. In this way, this review focuses on the different medical applications that can be achieved by 3D printing of bioinert ceramics, as well as on the latest advances in the 3D printing of bioinert ceramics. Moreover, an in-depth comparison of the different AM technologies used in ceramics is presented to help choose the appropriate methods depending on the part geometry.

Efficient and sustainable short electric arc machining based on SKD-11 material

SKD11 has a wide range of applications in the tooling industry. However, due to its high mechanical strength and hardness, it is a difficult material to machine. To address the issues of low machining efficiency, severe tool electrode wear, and environmental pollution caused by traditional EDM, this paper proposes a more efficient and sustainable method of EDM production called short electric arc machining (SEAM). This paper discussed the mechanism of material removal by a short electric arc and then conducted experiments on SKD11 machining with various voltage parameters using a self-designed short electric arc milling machine, analysing the material removal rate (MRR), relative tool electrode wear ratio (REWR), and specific energy consumption (SEC) of the machined workpiece. The experimental results indicate that the maximum removal rate is 15,745 mm3/min, the REWR is significantly reduced to 1.4 %, and the energy consumption ratio is 76.84 KJ/cm3. Finally, the microscopic morphology and elemental composition of the workpiece and tool electrode were analyzed by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), and the variation of cross-sectional grains was analyzed by electron backscatter diffraction (EBSD).It can be concluded that the short-arc milling method discussed in this paper can provide an efficient machining method for difficult-to-machine materials.

Exceptional strain strengthening and tuning of mechanical properties of TiN

Transition-metal light-element (TMLE) compounds possess high mechanical strength and hardness desirable for wide-ranging applications; but these materials tend to suffer large loss of shear strength in the presence of a compressive stress normal to the shear plane, which greatly impairs structural integrity and hinders mechanical performances under many practical loading conditions. There is pressing need to explore stress-strain relations to set benchmarks and find mechanisms for property optimization among this broad class of materials. Here, we show by first-principles calculations that titanium nitride (TiN) exhibits strain-induced stress enhancement and homogeneity, rendering enhanced and more isotropic stress responses under diverse compression constrained shear deformation; TiN also exhibits contrasting ductile/brittle stress responses under indentation and wear strains with distinct normal-to-shear stress ratios. Moreover, we assess crystal-orientation dependent strengths to account for experimentally observed directional variations of hardness. Analysis of bonding evolution unveils intricate atomistic mechanisms that dictate the deformation modes and resulting stress responses under various practical loading conditions. Such exceptional strain strengthening and tuning of major mechanical properties makes TiN an exemplary case among TMLE compounds for elucidating strain induced strengthening and load-sensitive ductile/brittle characteristics. These results provide an accurate description and in-depth understanding of diverse calculated and measured properties of TiN and offer insights for further exploration of versatile loading and crystal-orientation dependent mechanical properties among the vast class of TMLE compounds. The present findings raise the prospects of rational design and optimization of these prominent materials tailored for wide-ranging experimental implementation and diverse application.

High critical current density and high-tolerance superconductivity in high-entropy alloy thin films

High-entropy alloy (HEA) superconductors—a new class of functional materials—can be utilized stably under extreme conditions, such as in space environments, owing to their high mechanical hardness and excellent irradiation tolerance. However, the feasibility of practical applications of HEA superconductors has not yet been demonstrated because the critical current density (Jc) for HEA superconductors has not yet been adequately characterized. Here, we report the fabrication of high-quality superconducting (SC) thin films of Ta–Nb–Hf–Zr–Ti HEAs via a pulsed laser deposition. The thin films exhibit a large Jc of >1 MA cm−2 at 4.2 K and are therefore favorable for SC devices as well as large-scale applications. In addition, they show extremely robust superconductivity to irradiation-induced disorder controlled by the dose of Kr-ion irradiation. The superconductivity of the HEA films is more than 1000 times more resistant to displacement damage than that of other promising superconductors with technological applications, such as MgB2, Nb3Sn, Fe-based superconductors, and high-Tc cuprate superconductors. These results demonstrate that HEA superconductors have considerable potential for use under extreme conditions, such as in aerospace applications, nuclear fusion reactors, and high-field SC magnets.

An Experimental Investigation of Martensitic Stainless Steel in Aircraft and Aerospace Industry for Thermal Wear Performance and Corrosion Potential

Abstract Martensitic stainless steels are commonly prefered in industries requiring high mechanical strength, corrosion resistance, and hardness. The dry sliding wear behavior of 15-5 precipitation-hardenable (PH) martensitic stainless steel was investigated in a heat chamber with ball-on-disc tribometer under room temperature (RT), 100 °C, 200 °C, and 300 °C. The wear tracks were characterized using SEM, EDS, WCM and XRD. The results showed that wear resistance improved proportionally with increasing temperature and increased surface hardness enabled coefficient of friction to decrease. Corrosion rate decreased with increasing temperature owing to natural passivation film on stainless steel specimens. In comparison with RT and 300 °C tests, hardness increased from 341 HV0.1 to 401 HV0.1 and wear rate lowered by 94 %. It was shown that application and operation of 15-5 PH stainless steels is eligible in aircraft and aerospace industry.

The Molecular and Mechanical Characteristics of Biomimetic Composite Dental Materials Composed of Nanocrystalline Hydroxyapatite and Light-Cured Adhesive.

The application of biomimetic strategies and nanotechnologies (nanodentology) has led to numerous innovations and provided a considerable impetus by creating a new class of modern adhesion restoration materials, including different nanofillers. An analysis of the molecular properties of biomimetic adhesives was performed in this work to find the optimal composition that provides high polymerisation and mechanical hardness. Nanocrystalline carbonate-substituted calcium hydroxyapatite (nano-cHAp) was used as the filler of the light-cured adhesive Bis-GMA (bisphenol A-glycidyl methacrylate). The characteristics of this substance correspond to the apatite of human enamel and dentin, as well as to the biogenic source of calcium: avian eggshells. The introduction and distribution of nano-cHAp fillers in the adhesive matrix resulted in changes in chemical bonding, which were observed using Fourier transform infrared (FTIR) spectroscopy. As a result of the chemical bonding, the Vickers hardness (VH) and the degree of conversion under photopolymerisation of the nano-cHAp/Bis-GMA adhesive increased for the specified concentration of nanofiller. This result could contribute to the application of the developed biomimetic adhesives and the clinical success of restorations.

Simultaneously achieving high ZT and mechanical hardness in highly alloyed GeTe with symmetric nanodomains

For the application of thermoelectric materials, high figure-of-merit, ZT, endows them high energy conversion efficiency, while robust mechanical hardness makes them tolerable to a large thermal stress and elongates their service life. Hence, both high ZT and high mechanical hardness are necessary for the application of thermoelectric materials. Here, we report the simultaneous achievement of high ZT and robust mechanical hardness in highly alloyed GeTe with symmetric nanodomains. By proper structural symmetry engineering via Mn-substitution at Ge site, highly symmetric cubic GeTe nanodomains have formed, which strengthens phonon scattering together with dense point defects, and correspondingly approaches the amorphous limit of lattice thermal conductivity. Simultaneously, the optimized carrier concentration and additional band convergence lead to high electrical performance. Correspondingly, an enhanced ZT of ∼ 2.3 in Ge0.82Pb0.1Bi0.04Mn0.04Te at 573 K with an average ZT of ∼ 1.6 (300 K to 723 K) is achieved, which refers to a maximum energy conversion efficiency of ∼ 17 % at temperature difference of 400 K. Moreover, the hierarchical structure features results in high Vickers hardness up to ∼ 207 Kgf mm−2 in the Ge0.82Pb0.1Bi0.04Mn0.04Te. Our study indicates that structural symmetry engineering in highly alloyed GeTe can simultaneously approach significantly increased ZT and mechanical hardness, which can inspire new exploration and application of GeTe-based materials.

Novel Composite Nitride Nanoceramics from Reaction-Mixed Nanocrystalline Powders in the System Aluminum Nitride AlN/Gallium Nitride GaN/Titanium Nitride TiN (Al:Ga:Ti = 1:1:1).

A study is presented on the synthesis of reaction-mixed nitride nanopowders in the reference system of aluminium nitride AlN, gallium nitride GaN, and titanium nitride TiN (Al:Ga:Ti = 1:1:1) followed by their high-pressure and high-temperature sintering towards novel multi-nitride composite nanoceramics. The synthesis starts with a 4 h reflux in hexane of the mixture of the respective metal dimethylamides, which is followed by hexane evacuation, and reactions of the residue in liquid ammonia at −33 °C to afford a mixed metal amide/imide precursor. Plausible equilibration towards a bimetallic Al/Ga-dimethylamide compound upon mixing of the solutions of the individual metal-dimethylamide precursors containing dimeric {Al[N(CH3)2]3}2 and dimeric {Ga[N(CH3)2]3}2 is confirmed by 1H- and 13C{H}-NMR spectroscopy in C6D6 solution. The precursor is pyrolyzed under ammonia at 800 and 950 °C yielding, respectively, two different reaction-mixed composite nitride nanopowders. The latter are subjected to no-additive high-pressure and high-temperature sintering under conditions either conservative for the initial powder nanocrystallinity (650 °C, 7.7 GPa) or promoting crystal growth/recrystallization and, possibly, solid solution formation via reactions of AlN and GaN towards Al0.5Ga0.5N (1000 and 1100 °C, 7.7 GPa). The sintered composite pellets show moderately high mechanical hardness as determined by the Vicker’s method. The starting nanopowders and resulting nanoceramics are characterized by powder XRD, Raman spectroscopy, and SEM/EDX. It is demonstrated that, in addition to the multi-nitride composite nanoceramics of hexagonal AlN/hexagonal GaN/cubic TiN, under specific conditions the novel composite nanoceramics made of hexagonal Al0.5Ga0.5N and cubic TiN can be prepared.

Acid-responsive PEGylated branching PLGA nanoparticles integrated into dissolving microneedles enhance local treatment of arthritis

• Calcium carbonate-hybridized nanocarrier achieved acid-responsive release of cargo. • PEGylated multi-armed PLGA has high drug loading and immune escape functions. • The improvement in arthritis involved regulating the VEGF, JAK2 and STAT3 pathways. • Peach gum will become an alternative for dissolving microneedle substrates. • Functionalized nanoparticles integrated with microneedles enhanced drug delivery. The low drug-loading and permeation enhancement abilities of PLGA nanoparticles limit their use as transdermal delivery vehicles. We recently designed PEGylated star-shaped PLGA, which hybridized with calcium carbonate to form nanoparticles [6 s-NPs (CaCO 3 )] with immune stealth and acid-responsive properties, which increased the loading of tetrandrine (Tet), a poorly soluble antiarthritis active ingredient, by 3.26-fold compared with that of single-chain PLGA nanoparticles. The 6 s-NPs (CaCO 3 ) resulted in acid-responsive release of more cargo in both in vitro release medium (pH 5.5) and fibroblast-like synoviocytes (FLSs) ( p < 0.0001), thereby inducing stronger cytotoxic effects of the loaded Tet on the TNF-α-induced abnormal proliferation of FLSs than Tet-loaded 6 s-NPs (no CaCO 3 ) and Tet aqueous dispersion (Free Tet) ( p < 0.0001). However, the number of 6 s-NPs (CaCO 3 ) incorporated by RAW264.7 cells was significantly lower than that of PLGA nanoparticles without PEGylation-endowed immune escape function. Furthermore, the nanoparticles were integrated into peach gum-fabricated dissolving microneedles with higher mechanical hardness and better physical stability than hyaluronic acid-formed microneedles. This integrated delivery strategy dramatically increased synovial uptake of Tet via the transdermal route and was further enhanced by the cofunctionalization with stealth escape from phagocytes and inflammatory acidity-triggered release. The observed improvement in adjuvant-induced arthritis involved stronger regulation of the VEGF, JAK2/p-JAK2, and STAT3/p-STAT3 pathways, which was superior to deleting certain currently designed delivery capacities. This newly fabricated multifunctional transdermal vehicle is therefore a promising therapeutic approach for protecting against local inflammation.