Conventional Filler Research Articles

Capability of martensitic low transformation temperature welding consumables for increasing the fatigue strength of high strength steel joints

Abstract The use of low transformation temperature (LTT) filler materials represents a smart approach for increasing the fatigue strength of welded high strength steel structures apart from the usual procedures of post weld treatment. The main mechanism is based on the effect of the low start temperature of martensite formation on the stress already present during welding. Thus, compressive residual stress formed due to constrained volume expansion in connection with phase transformation become highly effective. Furthermore, the weld metal has a high hardness that can delay the formation of fatigue cracks but also leads to low toughness. Fundamental investigations on the weldability of an LTT filler material are presented in this work, including the characterization of the weld microstructure, its hardness, phase transformation temperature and mechanical properties. Special attention was applied to avoid imperfections in order to ensure a high weld quality for subsequent fatigue testing. Fatigue tests were conducted on the welded joints of the base materials S355J2 and S960QL using conventional filler materials as a comparison to the LTT filler. Butt joints were used with a variation in the weld type (DY-weld and V-weld). In addition, a component-like specimen (longitudinal stiffener) was investigated where the LTT filler material was applied as an additional layer. The joints were characterized with respect to residual stress, its stability during cyclic loading and microstructure. The results show that the application of LTT consumables leads to a significant increase in fatigue strength when basic design guidelines are followed. This enables a benefit from the lightweight design potential of high-strength steel grades.

Joining of Stainless Steel with Novel Filler Material and its Weldability Studies

Welding of Austenitic Stainless steels results in the emission of hexavalent chromium [Cr+6] fumes due to the presence of 18-22% chromium content in the stainless steel base and its filler materials. These hexavalent fumes are carcinogenic and cause respiratory problems to the welders and personnel in the vicinity of welding. In the present research work, novel Chromium free Nickel-based filler material of % wt composition 41 Ni, 8 Co, 16 Fe, 14Mo, 7 Mn, 8 Cu, 3 Nb, 1 Ti, 1 Si, 1 Al is developed and its weldability with stainless steel is studied. The microstructure and chemical composition of different metallurgical phases in the filler material and weld joints are studied using different microscopy tools and X-Ray Diffraction, respectively. The ultimate tensile strength of the filler material and weld joint welded by developed filler material is found to be 536MPa and 487 MPa, respectively. The average hardness and toughness of the filler material and welded joint are 190VHN &110J and 209VHN & 89 VHN, respectively. Results of Potentio-dynamic polarization and Inter Granular corrosion cracking (IGCC) of the weld joint has shown the corrosion rate of 1.575e-004 mils/year and 354.56 miles/year, respectively. Mechanical properties and corrosion rate of weldments welded by novel filler material are compared with that of conventional filler material. Design of experiments(DOE) using Taguchi L9 array is formulated to understand the influence of Welding current, root gap, and gas flow rate on output parameters such as Tensile Strength, Toughness, and corrosion resistance of weldment. DOE using RSM has shown maximum Tensile strength of 487Mpa, maximum Hardness of 209 VHN, and a minimum corrosion rate of 1.575e-004 mils/year has obtained with an optimum current value of 130A, 11.79 litres/min gas flow rate, and 2.33mm root gap.

Reduction of distortion by using the low transformation temperature effect for high alloy steels in electron beam welding

Residual stress and distortion of welded specimens are issues when it comes to geometrical requirements. The surrounding material prevents the dilatation associated with transformation in the area of heat input resulting in residual stress and distortion due to thermal contraction. In the past few years, low transformation temperature (LTT) material was successfully used as filler wire to reduce residual stress as well as distortion in the weld seam in arc welding processes. High alloy Fe-based filler materials with levels of chromium and nickel ensure a martensitic transformation at reduced temperatures in a low alloy base material. The LTT properties counteract the accumulation of stresses due to thermal contraction with compressive stresses that develop within the transformed region. This work used a high alloy base material in combination with a low alloy filler wire resulting in a microstructure that shows the same properties as LTT weld metals. This in situ alloying allows for an alloy composition tailored to the process. In order to provide a point of reference, comparable welds were made using conventional high alloy filler wire. As a result, the distortion and longitudinal residual stress was significantly reduced compared to welding with conventional filler wire.

Thermal and flammability properties of wollastonite-filled thermoplastic composites: a review

Wollastonite has a huge potential to be utilized as a functional filler in the thermoplastic composites, providing an enhancement to the mechanical strength, as well as thermal stability and flame retardancy, thus replacing the other conventional fillers such as glass fibre and talc. Due to the reinforcing ability and good thermal stability of wollastonite, the wollastonite-filled polymer composites have attracted the attention of academicians and industrialists. Many studies are reported on the effect of wollastonite incorporation into the polymers, in the aspect of mechanical, thermal, and flammability properties, meanwhile exploring the potential of wollastonite usage in the desired applications. This review article will be focusing on the thermal and flammability properties of wollastonite-filled thermoplastic composites. The popular thermoplastics used as the matrix are polypropylene, polylactic acid, and poly(ethylene terephthalate). Studies on flammability properties of wollastonite-filled thermoplastic composites are relatively less compared to thermal properties. Generally, the properties of the composites are influenced by the wollastonite dispersion, loading, size and shape of wollastonite, and its interfacial adhesion with the polymer matrix. Most of the previous studies focused on thermoplastic filled natural micro-sized wollastonite composites. Thus, the effect of nano-sized synthetic wollastonite as a functional filler in polymers is worth investigating. Further research on hybrid wollastonite/nanofillers is also interesting to develop high-performance materials to meet the requirements of society and industries.

Capability of martensitic low transformation temperature welding consumables for increasing the fatigue strength of high strength steel joints

Abstract The use of low transformation temperature (LTT) filler materials represents a smart approach for increasing the fatigue strength of welded high strength steel structures apart from the usual procedures of post weld treatment. The main mechanism is based on the effect of the low start temperature of martensite formation on the stress already present during welding. Thus, compressive residual stress formed due to constrained volume expansion in connection with phase transformation become highly effective. Furthermore, the weld metal has a high hardness that can delay the formation of fatigue cracks but also leads to low toughness. Fundamental investigations on the weldability of an LTT filler material are presented in this work, including the characterization of the weld microstructure, its hardness, phase transformation temperature and mechanical properties. Special attention was applied to avoid imperfections in order to ensure a high weld quality for subsequent fatigue testing. Fatigue tests were conducted on the welded joints of the base materials S355J2 and S960QL using conventional filler materials as a comparison to the LTT filler. Butt joints were used with a variation in the weld type (DY-weld and V-weld). In addition, a component-like specimen (longitudinal stiffener) was investigated where the LTT filler material was applied as an additional layer. The joints were characterized with respect to residual stress, its stability during cyclic loading and microstructure. The results show that the application of LTT consumables leads to a significant increase in fatigue strength when basic design guidelines are followed. This enables a benefit from the lightweight design potential of high-strength steel grades.

Predicting Marshall stability and flow of bituminous mix containing waste fillers by fuzzy logic

The practice of using different non-biddable wastes in place of conventional filler is successively extended nowadays, leading it hard to predict the properties of modified bituminous mixes. The present work aims to explore the effect of using rice husk ash (RHA) and fly ash (FA) as alternative filler in place of conventional filler like hydrated lime (HL) on Marshall stability and flow of bituminous mix by fuzzy logic. This study involves the preparation of samples having seven different bitumen content varying from 3.5% to 6.5% with 0.5% increment. Mixtures containing 2%, 4%, 6% and 8% of HL, RHA and FA separately as filler were fabricated and compared with the control mix (i.e. mix containing 2% hydrated lime as filler). Further, the Marshall mix design procedure was followed to determine the optimum bitumen content (OBC) of each mix. Experimental results showed that the replacement of conventional filler with RHA and FA improved the Marshall properties and decreases the OBC values of the modified mix when added with 4% filler ratio. Further, for predicting the Marshall stability and flow, a Mamdani-type fuzzy inference system model was devised in Matlab toolbox using percentage bitumen, air voids, percentage of HL, RHA and FA as input and Marshall stability and flow as output. In comparison, it is realized that predicted values are closely relevant to the actual one and the prediction ability of the fuzzy logic model is suitable for getting the said values by avoiding the expensive, time consuming and repetitive laboratory tests.

An evaluation of the performance of hot mix asphalt containing calcium carbide residue as a filler

The reduction of both environmental problems and construction costs has motivated the asphalt pavement industry to increasingly use waste materials as alternative raw materials in road pavements construction. This investigation aims to explore the potential of waste calcium carbide residue (CCR) for use as a filler in hot mix asphalt (HMA), by substituting traditional limestone filler in various proportions. Asphalt mixes were prepared using different CCR ratios (0%, 3% and 6%) by aggregate dry weight, their strength, properties and performance evaluated against the indirect tensile stiffness modulus, rutting, crack initiation, crack propagation and moisture damage. The results show that stiffness modulus and resistance to permanent deformation and cracks have been enhanced due to the addition of CCR. HMA modified with CCR was also found to be less sensitive to water damage than traditional HMA with limestone filler. A toxicity characteristic leaching procedure (TCLP) test revealed that the CCR used in the production of HMA has no environmental impact. Therefore, based on this study, CCR can be considered as a plausible alternative to conventional filler in HMA, the implication being that large amounts of waste carbide lime can be removed from landfill, thereby significantly reducing environmental damage.

Development of Chlorhexidine Loaded Halloysite Nanotube Based Experimental Resin Composite with Enhanced Physico-Mechanical and Biological Properties for Dental Applications

Objective: The objective of this study was to explore the effect of Chlorhexidine-loaded Halloysite nanotubes (HNT/CHX) fillers (diverse mass fractions from 1 to 10 wt.%) on physicochemical, morphological and biological properties of newly developed experimental dental resin composite, in order to compare with the properties of composites composed of conventional glass fillers. Methods: The dental resin composites were prepared by incorporating various proportions of HNT/CHX. Six different groups of specimens: control group and five groups composed of varied mass fractions of HNT/CHX (e.g., 1.0, 2.5, 5.0, 7.5 and 10 wt.%) as fillers in each group were fabricated. Mechanical properties of the composites were monitored, using UTM. The degree of conversion of dental resin composites and their depth of cure were also evaluated. Antimicrobial properties of dental composites were studied in vitro by applying agar diffusion test on strain Streptococcus mutans and cytotoxicity were studied using NIH-3T3 cell line. Results: The incorporation of varied mass fractions (1.0 to 5.0 wt.%) of HNT/CHX in dental resins composites enhanced mechanical properties considerably with significant antibacterial activity. The slight decrease in curing depth and degree of conversion values of composites indicates its durability. No cytotoxicity was noticed on NIH-3T3 cell lines. Significance: Consistent distribution of HNT/CHX as a filler into dental composites could substantially improve not only mechanical properties but also biological properties of dental composites.

Solidification Cracking Assessment of LTT Filler Materials by Means of Varestraint Testing and µCT.

Investigations of the weldability of metals often deal with hot cracking, as one of the most dreaded imperfections during weld fabrication. The hot cracking investigations presented in this paper were carried out as part of a study on the development of low transformation temperature (LTT) weld filler materials. These alloys allow to mitigate tensile residual stresses that usually arise during welding using conventional weld filler materials. By this means, higher fatigue strength and higher lifetimes of the weld can be achieved. However, LTT weld filler materials are for example, high-alloyed Cr/Ni steels that are susceptible to the formation of hot cracks. To assess hot cracking, we applied the standardized modified varestraint transvarestraint hot cracking test (MVT), which is well appropriate to evaluate different base or filler materials with regard to their hot cracking susceptibility. In order to consider the complete material volume for the assessment of hot cracking, we additionally applied microfocus X-ray computer tomography (µCT). It is shown that by a suitable selection of welding and MVT parameter the analysis of the complete 3D hot crack network can provide additional information with regard to the hot cracking model following Prokhorov. It is now possible to determine easy accessible substitute values (e.g., maximum crack depth) for the extent of the Brittleness Temperature Range (BTR) and the minimum critical strain .

Agricultural wastes as renewable fillers in physical granulation of NPK fertilizers: Evaluation of on-size granules and comparison to conventional filler

Purpose This research aimed to evaluate the yield and quality of granular NPK fertilizers prepared by physical granulation with eggshell, snail shell, and cow bone as fillers and to compare them to conventional filler. Methods Urea, DAP, KCl, and fillers were milled separately and mixed to the desired formula. About 150 g of mixed powders were granulated on a disc granulator in 9 minutes, at a rotation speed of 35 rpm and a disc slope of 45°. Water at a desired additional moisture was sprayed on the tumbled powders to facilitate the granulation. The obtained granules were then dried and screened into three fractions: undersize ( 4 mm). Results Snail shells and eggshells as fillers were found to give on-size NPK granules having yield and compressive strength which were comparable to that with limestone as a conventional filler. For NPK 15-15-15, using snail shells and eggshells as fillers, the yields of on-size granules achieved 46% and 56%, respectively, and the compressive strengths of on-size granules reached 2.4 and 2.1 MPa, respectively. Cow bones as fillers resulted in low compressive strength. The distribution of nutrients in the NPK granules was found to be close to the targeted formula. Conclusion Snail shells and eggshells as fillers have good yield and quality of on-size NPK granules and are very potential alternatives to limestone.

PVA-Based Mixed Matrix Membranes Comprising ZSM-5 for Cations Separation.

The traditional ion-exchange membranes face the trade-off effect between the ion flux and perm-selectivity, which limits their application for selective ion separation. Herein, we amalgamated various amounts of the ZSM-5 with the polyvinyl alcohol as ions transport pathways to improve the permeability of monovalent cations and exclusively reject the divalent cations. The highest contents of ZSM-5 in the mixed matrix membranes (MMMs) can be extended up to 60 wt% while the MMMs with optimized content (50 wt%) achieved high perm-selectivity of 34.4 and 3.7 for H+/Zn2+ and Li+/Mg2+ systems, respectively. The obtained results are high in comparison with the commercial CSO membrane. The presence of cationic exchange sites in the ZSM-5 initiated the fast transport of proton, while the microporous crystalline morphology restricted the active transport of larger hydrated cations from the solutions. Moreover, the participating sites and porosity of ZSM-5 granted continuous channels for ions electromigration in order to give high limiting current density to the MMMs. The SEM analysis further exhibited that using ZSM-5 as conventional fillers, gave a uniform and homogenous formation to the membranes. However, the optimized amount of fillers and the assortment of a proper dispersion phase are two critical aspects and must be considered to avoid defects and agglomeration of these enhancers during the formation of membranes.

Eco-friendly ultra-high performance cement pastes produced with quarry wastes as alternative fillers

About 35 billion tons of quarried material are produced annually throughout the world, generating large amounts of waste powders which are usually disposed of in landfills. This work investigated the feasibility of producing eco-friendly ultra-high performance cement pastes with diabase, granite and basalt quarry wastes as alternatives to quartz and limestone conventional fillers. The fresh properties (rheometry and mini slump), hydration (calorimetry, TGA and XRD), 3- and 28-day strength and microstructure (SEM-EDS) of the pastes were investigated. The results showed that granite and diabase fillers increased the yield stress of the pastes by about 1.6 times compared with quartz and limestone, while basalt increased it by 9 times. Only granite increased the apparent viscosity due to the irregular shape and rough texture of its particles. All the pastes presented self-levelling aspect. Calorimetry indicated equivalent hydration kinetics for quartz, granite and basalt, while limestone and diabase shortened the induction period and elevated the 72-h cumulative heat by 5%. XRD and TGA indicated similar compositions for all the pastes (calcium hydroxide and hydrates contents respectively of 6.8 ± 0.4% and 13.4 ± 0.4% at 28 days), and no evidence of pozzolanic activity by the fillers. All the mixes presented 3- and 28-day compressive strengths respectively of 71 ± 3 MPa and 132 ± 2 MPa, indicating that the incorporation of the quarry fillers did not lead to significant differences in strength. In line with that, SEM-EDS indicated similar microstructures. Overall, the alternative quarry powders can be used in the production of ultra-high performance cementitious composites with no impairments on its fresh, hardened and microstructural characteristics, contributing to the eco-efficiency of construction.

Highly thermally conductive polypropylene/graphene composites for thermal management

As an indispensable part of electronic devices, efficient thermal management materials can promote heat dissipation of electronic products quickly, thereby greatly improving their reliability, stability and service life. Here, a simple “in-situ building” approach was developed to fabricate highly thermally conductive polypropylene (PP)/graphene composites with three-dimensional graphene framework. Different from conventional filler modification, a unique matrix functionalization method, inspired by mussel, was carried out to form the interaction (hydrogen bonding and π-π conjugate) between PP and graphene, which greatly reduced interfacial thermal resistance. The obtained composite exhibits a quite high through-plane thermal conductivity (10.93 W·m−1·K−1, almost 55 times higher than that of pure PP), and shows excellent heat dissipation when used as a thermal management material in LED integration. The composite has the potential application in heat dissipation of high power and highly integrated electronic devices.

Sulfur and peroxide curing of rubber magnetic composites with the application of zinc methacrylate

Rubber magnetic composites based on acrylonitrile butadiene rubber and strontium ferrite were cured with standard sulfur-based vulcanization systems as well as an organic peroxide. Zinc methacrylate (ZDMA) as a coagent was applied in both sulfur and peroxide vulcanization of rubber magnets. The aim was to evaluate the influence of ZDMA on curing characteristics and cross-link density of the prepared materials. Subsequently, physical-mechanical and magnetic properties were investigated. The results showed that ZDMA takes an active part in the cross-linking process of composites cured with an organic peroxide. Due to the presence of free radicals formed from peroxide decomposition, molecules of ZDMA polymerize into the nanostructures which can be physically adsorbed or chemically grafted onto rubber chains. Moreover, owing to zinc ions, ZDMA exhibits strong adhesion to ferrite filler and thus it contributes to the improvement of adhesion between the rubber and the filler on the interphase. The overall reinforcement of rubber magnetic composites was subsequently achieved. In the case of rubber magnets cured with the sulfur-based system, ZDMA acts as a conventional filler with a slight reinforcing effect due to the lack of free radicals required for its polymerization.

Comparative biological assessments of endodontic root canal sealer containing surface pre-reacted glass-ionomer (S-PRG) filler or silica filler.

Surface pre-reacted glass-ionomer (S-PRG) filler releases several ions, such as fluoride, borate and strontium ions, to exert bioactive effects. We fabricated an endodontic root canal sealer containing S-PRG fillers (S-PRG sealer) and then evaluated the antibacterial and anti-inflammatory properties of S-PRG sealer compared with sealer containing conventional silica fillers (silica sealer). Antibacterial tests showed that S-PRG sealer significantly reduced the turbidity of Enterococcus faecalis compared with silica sealer. Implantation of S-PRG or silica sealer blocks in rat subcutaneous tissue showed that S-PRG sealer decreased the proinflammatory response compared with silica sealer at 10 days post-implantation. In addition, immunostaining revealed that infiltration of CD68- and peroxidase-positive cells around the S-PRG sealer was significantly lower than that in silica sealer. Therefore, it was suggested that S-PRG sealer exhibits antibacterial and anti-inflammatory effects.

A novel high entropy CoFeCrNiCu alloy filler to braze SiC ceramics

In order to reduce intermetallic compound formations in brazed joints, a CoFeCrNiCu high entropy alloy was invented and employed to braze SiC ceramics. Results show that SiC ceramics were tightly and strongly brazed with the CoFeCrNiCu filler. Microstructure, phase and shear strength were systematically studied for joints brazed at different temperature. Main compositions were identified as high-entropy FCC, Cu(s, s), Si(s, s), and Cr23C6 phases, regardless the brazing temperature differences. After being brazed at 1453 K, the joint reached a maximum shear strength of 60 MPa, much higher than those brazed with conventional AgCuTi filler. Thanks to high entropy effect of CoFeCrNiCu filler, random solid solution turned out in the seam and benefitted joint quality. The successful use of CoFeCrNiCu high entropy alloy as fillers can expand the application range of high entropy alloys and provide a new filler system to braze ceramics.

Light weight HTPB-clay nanocomposites (HCN) with enhanced ablation performance as inhibition materials for composite propellant

In the present study, organically modified Montmorillonite clay with polar moiety, the Cloisite 30B, is used for preparation of Hydroxyl terminated polybutadiene (HTPB)-clay nanocomposites (HCN) by dispersion of nanoclay in polymer matrix under high shear mixing. The nanocomposites thus prepared are evaluated in composite propellants as inhibitor material for their functional utility. Several inhibition formulations containing 5 wt%-15 wt% of nanoclay, with or without the conventional filler Sb2O3, were prepared. All these formulations were evaluated for their physical, mechanical, thermal, and ablative properties. Ablation rate and density of the compositions containing Cloisite 30B is around 23% and 5% lower respectively in comparison of the base composition. Strain capability of these compositions is twofold higher than that of base composition. These compositions have also been evaluated for their smoke generation tendency by measuring infra red (IR) attenuation in the wavelength range 1.3 μm–5.6 μm and 8 μm–13 μm and thereby compared with the base composition. The corresponding results confirmed that the compositions containing Cloisite 30B as filler have much lower IR attenuation than compositions with conventional filler, Sb2O3. Replacement of 5% Sb2O3 by nanoclay showed 8% reduction in IR attenuation rate which further reduced to 16% on replacement of 15% of Sb2O3. Interfacial bonding of HCN based inhibitors is also comparable or even better than conventional inhibitors. Precisely, the nanoclay composites with Cloisite 30B as filler exhibit all desirable properties of an inhibitor.

Investigating the Influence of Replacing Two Biomass Ashes with Conventional Filler on High and Intermediate Temperature Performance of Mastic and Mixture

Abstract The aim of this research was to evaluate the rheological properties of mastics and performance of mixtures consisting of two biomass ashes named as coal waste ash (CWA) and rice husk ash (RHA) used as a replacement of limestone filler at different concentrations. The high and intermediate temperature behavior of binders was evaluated through multiple stress creep recovery (MSCR) and linear amplitude sweep (LAS) tests. Moreover, Marshall stability, resilient modulus, dynamic creep, moisture susceptibility, wheel track, indirect tensile strength, and four-point beam fatigue tests were implemented to investigate the mechanical performance of mixtures. Based on MSCR test results utilization of RHA led to improve the rutting resistance of binders, while CWA decreases the rutting resistance of binders. LAS test results indicated that addition of RHA to original binder increase the fatigue life of binder, while CWA decreases the fatigue behavior of mastics. Based on the results, the addition of styrene-butadiene-styrene (SBS) increases the fatigue life of mastics. Results revealed that the addition of RHA improves the Marshall stability, resilient modulus, rutting properties, moisture resistance, and tensile strength of asphalt mixtures, while CWA has negative impact. In general, the obtained results from this study indicated that reuse of RHA and CWA waste materials in the northern part of Iran, where there are lots of RHA and CWA materials, especially RHA, in pavement engineering, has two main effects. First, environmental problems are reduced. Second, the performance properties of mixtures are enhanced.

Investigating plasma keyhole welding with multiple wires for fusion welding with chemically graded weld seams

Fusion welding processes are characterised by high temperature gradients, caused by the local heat input, which in turn leads to the formation of thermal and transformation induced (tensile-) stress. If the resulting stress exceeds the yield point, distortion occurs, which has a strong influence on the geometrical precision of the component. To counter these effects, in the past few years Low Transformation Temperature (LTT) materials were successfully used as filler wire. Here, the martensite start temperature is reduced and the increased thermal expansion during the martensitic phase transformation is used to induce compressive stress. Thus the formation of tensile stress through thermal shrinkage can be actively counteracted by the formation of compressive stress at reduced temperature. This counteracts the thermal distortion with the use of phase transformation. However, a solid technical solution for locally inducing LTT injections needs to be found. The following article presents a new approach of generating chemically graded weld seams in order to change the microstructure from ferritic to martensitic LTT alloy within the welding process. Therefore, a multi-wire plasma keyhole process is used to create a new alloy in-situ with varying nickel and chromium contents. To obtain a chemically graded structure the wire feed speeds are changed continuously within the welding process. For the multi-wire plasma keyhole process, a conventional plasma welding torch is extended by additional wire feeders, developed by the RWTH Aachen University Welding and Joining Institute. The graded structure is achieved by combining a high chromium-nickel filler wire with a conventional low alloy filler wire. The length of the graded area is varied so that the transition from high to low alloy area is either long or short. The results show, that it is possible to establish a stable welding process and change the chemical composition within the weld seam in-situ. Cross sections show a changing microstructure from low alloy ferritic microstructure to a martensitic microstructure. The influence of the transition area on the resulting microstructure and mechanical properties, such as hardness, is investigated. The experiments were performed in order to develop a basic knowledge about the mixing of dissimilar materials in plasma keyhole welding and the effects on the microstructure.

Physicochemical and biological assessment of silver nanoparticles immobilized Halloysite nanotubes-based resin composite for dental applications

ObjectiveThe purpose of this study was to investigate the effect of Silver nanoparticle immobilized Halloysite Nanotubes (HNT/Ag) fillers on physicochemical, mechanical, and biological properties of novel experimental dental resin composite in order to compare with the properties of corresponding composites containing conventional glass fillers. MethodsDental resin (Bis-GMA/TEGDMA with ratio 70/30) composites were prepared by incorporation of varied mass fraction of HNT/Ag. Experimental composites were divided into six groups, one control group and five experimental groups containing mass fraction 1 to 10.0 wt. % of HNT/Ag. Mechanical properties of the dental composites were recorded. Degree of conversion and depth of cure of the dental resin composites were assessed. Antimicrobial properties were assessed using agar diffusion test and evaluation of cytotoxicity were performed on NIH-3T3 cell line. ResultsThe inclusion of mass fractions (1–5 wt. %) of the HNT/Ag in dental resins composites, significantly improved mechanical properties. While, addition of larger mass fractions (7.5 and 10 wt. %) of the HNT/Ag did not show further improvement in the mechanical properties of dental resins composites. Theses composites also demonstrated satisfactory depth of cure and degree of conversion. A significant antibacterial activity was observed on S. mutans. No significant cytotoxicity was found on NIH-3T3 cell lines. ConclusionThe incorporation of HNT/Ag in Bis-GMA/TEGDMA dental resins composites resulted in enhancement in mechanical as well as biological properties for dental applications. Clinical significanceHNT/Ag containing dental composite is proposed to be highly valuable in the development of restorative dental material for patients with high risk of dental caries.