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In order to forecast and regulate the quality of the weld with improved mechanical qualities while automating the welding process for an increased production rate, a relationship between the process parameters must be developed. The relationship between the welding parameters and the mechanical properties can be easily tracked using the response surface methodology. The aim of this study is to optimize the parameters in the submerged arc welding of AISI 1055 steel using Box–Behnken design in response surface methodology. The metal deposition rate is more influenced by the current, which simultaneously improves the mechanical properties of the weld. The optimized process parameters are 349.94A for current, 52.90V for voltage, and 0.6m/min for carrier speed. These optimized performance parameters are 461.72N/mm² for ultimate tensile strength, 35.26J for impact strength, and 41.95HRC for hardness. The desirability of 0.718 is obtained for the developed optimization model, which proves the reliability of the model in the actual experimentation.

A pendulum-impact testing machine was developed to measure the impact strength of ball-grid-array (BGA) solder joints between an electronic package and a circuit board. Ball solders were connected to daisy-chain between a dummy electronic package and a circuit board. The upper side of the package was directly bonded to a load cell. The rear side of the circuit board was also bonded to an aluminum alloy block fixed on a base. A pendulum made of aluminum alloy was collided into the load cell to apply tensile impact to the solder joints through the load cell. The history of the impact load could be controlled by raising the angle of the pendulum. The fracture of a BGA solder joint was detected by measuring the resistance of the daisy-chain circuit on the board. Therefore, the impact strengths of the solder joints at electrical disconnection and mechanical breaking of all joints could be determined. The experimental results showed that this method is useful for measuring the impact strength of BGA solder joints.

A spacer grid assembly is one of the main structural components of the nuclear fuel assembly for a Pressurized light Water Reactor (PWR). The spacer grid assembly supports and aligns the fuel rods, guides the fuel assemblies past each other during a handling and, if needed, sustains lateral seismic loads. The ability of a spacer grid assembly to resist these lateral loads is usually characterized in terms of its dynamic and static crush strengths, which are acquired from tests. In this study, a finite element analysis on the dynamic crush strength of spacer grid assembly specimens is carried out. Comparisons show that the analysis results are in good agreement with the test results to within about a 30 % difference range. Therefore, we could predict the crush strength of a spacer grid assembly in advance, before performing a dynamic crush test. And also a parametric study on the crush strength of a spacer grid assembly is carried out by adjusting the weld penetration depth for a sub-sized spacer grid, which also shows a good agreement between the test and analysis results.

We study experimentally the influence of mass fraction of L-20 hardener cold cure on mechanical properties of epoxy diane resin ED-20. We measure the hardness, tensile strength, bending strength and impact strength of resin at different values of the hardener mass fraction. It is found that the ratio hardener mass fraction of 1:0.9 leads to the highest values of the hardness, tensile strength, compressive strength and bending strength. The impact viscosity is maximum at the ratio hardener mass fraction of 1:0.8. The optimal ratio of a non-toxic safe hardener to the resin is derived based on obtained mechanical characteristics.

Because particles that accumulate without movement can lead to a deposition gradient, the formation of a stable suspension is essential for the electrophoretic dispersion (EPD) process. The hydrophobic properties of Halloysite nanotubes (HNTs) were easily dispersed in many nonpolar polymers without further deformation steps. However, the uniform dispersion of HNTs in aqueous solutions is a pre-EPD process task. The zeta potential controls the main parameters of EPD processes, such as the density of deposits, particle orientation and velocity, and repulsive interactions between particles, which determine the stability of the suspension. In this study, the solution stability range for the addition of nanoparticles was measured and the optimal dispersion range was determined. In addition, an HNT-reinforced composite material was created by determining the optimal dispersion stability range of HNT, and the impact strength and fracture mechanism of the interface were analyzed. The solution stability and dispersion were the best between pH 6.6 and 6.8, and the highest impact strength was confirmed at 0.7 wt%. The HNT confirmed the interfacial dispersion of the EPD-fibers using scanning electron microscopy and dispersive X-ray spectroscopy (SEM-EDS).

In this study, hybrid polymer nanocomposites were produced by combining epoxy (EP) with varying amounts of zirconia (ZrO${}_2)$ and yttria (Y₂O${}_3)$ nanoparticles (NPs), reinforced with multi-walled carbon nanotube (MWCNT) and glass fiber (GF). The objective of this study is to develop and examine the performance of EP nanocomposites through hybridization; for this purpose, hardness and impact tests were conducted in accordance with American Society for Testing and Materials (ASTM) standards. Different sets were produced to investigate the effect of used fillers, including EP/ZrO₂, EP/Y₂O₃, EP/MWCNT, EP/GF, EP/ZrO₂/Y₂O₃, EP/MWCNT/ZrO₂/Y₂O₃, and EP/MWCNT/GF/ZrO₂/Y₂O₃. All findings were compared with the net EP sample. The results showed that the EP nanocomposite samples with low NPs content exhibit much higher mechanical performance than net EP. Furthermore, the additions of MWCNT and GF separately at 0.1 and 0.06wt.% have increased the impact strength, respectively, to 165.2% and 338.8%, compared with pure EP. As a result, the presence of MWCNTs and GF in the EP-based nanocomposite matrix could make the product both stronger and tougher.

The main purpose of this work is to optimize the mechanical properties of tungsten–copper (W–Cu) nanocomposite fabricated by the sintering process. For this purpose, the parameters of sintering temperature, sintering time and weight percentage of copper were selected to optimize the compression strength, impact strength, hardness and corrosion resistance of the W–Cu nanocomposite using the desirability function procedure and response surface method. The analyses of transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) were also performed to examine the microstructure of W–Cu nanocomposite. The results exhibited that a rise in the sintering temperature from 1000^∘C to 1150^∘C significantly enhanced the impact strength of W–Cu nanocomposite, while a rise in the sintering temperature from 1150^∘C to 1300^∘C deteriorated the impact strength. Moreover, the compression strength and hardness of the W–Cu nanocomposite continuously improved by elevation of sintering temperature from 1000^∘C to 1300^∘C. A rise in the amount of Cu from 20wt.% to 40wt.% led to a reduction in the hardness of the W–Cu nanocomposite, while a rise of Cu content improved the impact and compression strengths. The results also indicated that the mechanical properties of W–Cu nanocomposite enhanced simultaneously by using 27wt.% Cu at sintering temperature of 1197^∘C and sintering time of 2.7h. The samples sintered at the optimal conditions indicated a higher corrosion resistance than that sintered at the initial conditions.

Al7075 is employed as the matrix material and sugarcane bagasse ash (SBA) is a reinforcing material in this work, which is targeted at creating lightweight metal matrix composites (MMCs) at a reasonable cost. Hybridized improved composite castings have been produced and industrial as per ASTM standards with changing wt.% of 0%, 4%, 8%, 12%, and 16% wt.%, correspondingly, after mechanical testing for the evaluation of their strength. It is tested for hardness, tensile, impact, and flexural strength. Composites with hybrid enhanced metal matrix have greater tensile, hardness, and flexural strengths than single-reinforced MMCs. The composite’s tensile and flexural strengths were boosted by a 12wt.% increase in bagasse ash, which resulted in maximum values of 96.42% tensile and 23.58% flexural strength, respectively. As the bagasse weight percentage grew over 12%, these values fell, although Bagasse ash AA7075’s impact and ductility improved slightly.

Antibiotic-impregnated poly(methyl methacrylate) (PMMA) bone cement has been successfully used to treat infected joint arthroplasties and surgeons have advocated the use of antibiotic-treated bone cement to prevent possible infections in joint replacement surgeries. However, there is a concern that this addition may adversely affect the mechanical properties of the bone cement. In most cases, the addition of antibiotics to bone cement has been reported to lower its mechanical strength. The uniaxial, biaxial and three/four point bending tests of antibiotic-impregnated bone cement have been extensively performed and well documented. However, only a few documents have focused on the impact strength of bone cement. The present study reports the impact tests of control and antibiotic loaded bone cements at different temperatures and aging conditions. According to the results, the addition of gentamicin or vancomycin significantly reduced the samples' impact strength. Moreover, the samples aged in saline at 23${}^{\circ }$C were more resistant than the samples aged in air at 23${}^{\circ }$C. Furthermore, raising the storage temperature from 23${}^{\circ }$C to 37${}^{\circ }$C significantly lowered the bone cement's impact strength in both control and antibiotic loaded samples.

This study aims to prepare composite materials and improve some of their mechanical properties by using epoxy resin (EP) and polyurethane (PU) as the matrix material and nanoparticles (Al₂O₃) as reinforcing agents in different ratio with weight fractions (5%, 10%, and 15%). The results in the tables show that increasing the weight fraction of nanoparticles leads to an increase in the elasticity coefficient and durability of the impact and absorbed energy, with an increase in the temperature of the composite material reinforced with nanoaluminum oxide particles. The mechanical properties gradually decrease with the increase of the period of immersion in water.

This study focuses on achieving enhanced mechanical properties of the welded joints, which is critical for the applications of mild steel (MS) plates in various industries. In this regard, a systematic approach is used to adjust welding parameters such as welding current and workpiece thickness in shielded metal arc welding (SMAW), with the objective of identifying the optimal combination that maximizes weld quality. The experiments were planned with the help of Taguchi’s L9 orthogonal array method in order to reduce experimental cost and time. The weld quality is optimized by determining the signal-to-noise ratios of weld penetration, tensile strength, impact strength, and microhardness for each experimental sample. As a result, 110 A welding current is obtained as the optimal SMAW parameter for a 5 mm thick MS IS 2062 Grade B plate. This optimized result has also achieved 394.78 N/mm² tensile strength and 53 J of impact resistance for the respective specimen. Besides, research not only enhances understanding of the SMAW process but also offers practical implications for industries requiring high-performance welded joints in MS structures. Additionally, this study can assist upcoming researchers in optimizing any existing welding procedures.

Polyoxymethylene (POM)/elastomer/filler ternary composites were prepared, in which thermoplastic polyurethane (TPU) and inorganic filler, namely, CaCO₃, were used to achieve balanced mechanical properties of POM. The dispersion and phase morphology of POM/elastomer/filler composites were found to depend largely on processing method, CaCO₃ content in masterbatch and the filler size. Two processing methods were employed to prepare POM/elastomer/filler ternary composites. One is called the one-step method, in which elastomer and the filler directly melt blended with POM matrix. The other is called the two-step method, in which the elastomer and the filler were mixed to get masterbatch first, which was then melt blended with pure POM of different content. The effect of phase morphology and processing method on impact strength was investigated. It was found that the two-step method results in an increase in impact strength but not for the one-step method. Additionally, the impact strength of POM ternary composites decreases with the increase in the size of CaCO₃ particles.

Organoclay-modified hydroxylterminated polysulfone (PSF)/epoxy interpenetrating network nanocomposites (oM-PSF/EP nanocomposites) were prepared by adding organophilic montmorillonite (oMMT) to interpenetrating polymer networks (IPNs) of polysulfone and epoxy resin (PSF/EP) using diaminodiphenylmethane (DDM) as curing agent. The mechanical properties like tensile strength, tensile modulus, flexural strength, flexural modulus and impact properties of the nanocomposites were studied as per ASTM standards. Differential scanning calorimetry (DSC) analysis, dynamic mechanical analysis (DMA) and scanning electron microscopy (SEM) analysis showed that PSF was compatible with EP, and the glass transition temperature (T_g) of the oM-PSF/EP nanocomposites decreased with increasing the oMMT content. Water absorption tests showed that the PSF/EP interpenetrating networks and oMMT had synergistic effects on improvement in the water resistance of the oM-PSF/EP nanocomposites.

To enhance the impact strength of polyamide 6, hydrolytic polymerization modification by the polyaminoamide-g-poly(ethylene glycol) (PAAEG) derivatives with poly(ethylene glycol) (PEG) molecular weight of 400–10000 was studied. Amide groups of polyaminoamide segments were postulated to form hydrogen bonding with polyamide 6, and hydroxy groups of PAAEG units were expected to react with carboxylic acid groups of polyamide 6 forming copolymers during the polymerization. The improved compatibility in amorphous regions of blends has been confirmed by differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) of fracture surfaces. The effects of PAAEG on the water absorption and notch sensitivity of blends were investigated, using water uptake measurement and mechanical testings, respectively. For comparison, pure polyamide 6 and the blend of PEG/polyamide 6 were also investigated. The addition of PAAEG retarded the crystallization of polyamide 6, but did not make remarkable influences on its crystalline structure. As a consequence of the strong interactions between the dispersed phases and polyamide 6 matrices, PAAEG was a more suitable additive for improving the notched impact strength of polyamide 6 than PEG.

The present work investigates the novel impact loading response of two-dimensional graphene oxide (GO) reinforced epoxy nanocomposites at high strain rate. The testing was performed up to 1000s${}^{-1}$ of high strain rate, where maximum damage occurs during the impact loading conditions. The Split Hopkinson Pressure Bar (SHPB) was used for the impact loading of the composite specimen. The nanofiller material GO was synthesized by chemical oxidation of graphite flakes used as the precurser. Synthesized GO was characterized using FTIR, UV-visible, XRD, Raman Spectroscopy and FE-SEM. Solution mixing method was used to fabricate the nanocomposite samples having uniform dispersion of GO as confirmed from the SEM images. Strain gauges mounted on the SHPB showed regular signal of transmitted wave during high strain rate testing on SHPB, confirming the regular dispersion of both the phases. Results of the transmission signal showed that the solution mixing method was effective in the synthesis of almost defect-free nanocomposite samples. The strength of the nanocomposite improved significantly using 0.5wt.% reinforcement of GO in the epoxy matrix at high strain rate loading. The epoxy GO nanocomposite showed a 41% improvement in maximum stress at 815s${}^{-1}$ strain rate loading.