Tensile Testing Machine Research Articles

Tensile Force Limits of the Sheep Spine: Comparison to Forces Required to Extricate Grain Entrapped Victims

ABSTRACT Objectives Grain storage facility entrapments continue to be of concern in the agricultural industry, with nearly 1,500 documented incidents recorded over the last 45 years. Previous research studies have shown that attempting to extricate a full-size pulling test dummy from a grain mass requires a substantial amount of tensile or pull force – e.g. up to 1.32 kN if “buried” at waist depth, 2.77 kN at chest depth, and 4.01 kN at head depth. There is, however, a paucity of studies on the amount of distraction the human lumbar spine region can endure. The objective of this research study was to test the maximum tensile force that could be exerted on a sheep’s spine (comparable to the human spine) before the intervertebral discs and surrounding ligament would show signs of failure. Methods Eight lumbar-region sheep spine segments were axially distracted using an MTS Criterion tensile testing machine, and the maximum forces were recorded. Results The average maximum force that the spinal discs and ligament withstood before showing signs of failure was 2.14 kN (standard deviation of 0.31 kN). This is comparable to the force required to extricate an individual entrapped in a grain mass at chest depth. Conclusion The authors recommend that grain entrapment victims should not be forcefully pulled out if buried to waist level or above due to two primary reasons: (1) the large variation in failure load observed in our experiment with sheep spines and (2) the lack of knowledge regarding the victim’s pre-existing medical condition. The extractive forces required to remove a victim of entrapment in grain overlaps with the force needed to cause potential damage to the sheep spine, as the 1.7–3.0 kN range is comparable to the 1.65–2.48 kN force range that causes axial failure in the spine.

Effect of Co Addition on the Microstructure and Mechanical Properties of Sn-11Sb-6Cu Babbitt Alloy

A Babbitt alloy SnSb11Cu6 with 0–2.0 wt.% Co was synthesized using the induction melting process. This study examined the effect of cobalt (Co) on the microstructure, tensile properties, compressive properties, Brinell hardness, and wear properties of SnSb11Cu6 using optical microscopy (OM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), a universal tensile testing machine, a Brinell hardness tester, and a wear testing machine. The results indicate that the optimal quantity of Co can enhance the microstructure of the Babbitt alloy and promote microstructure uniformity, with presence of Co3Sn2 in the matrix. With the increase in Co content, the tensile and compressive strength of the Babbitt alloy first increased and then decreased, and the Brinell hardness gradually increased with the increase in Co content. The presence of trace Co has a minimal effect on the dry friction coefficient of the Babbitt alloy. When the Co content exceeds 1.5 wt.%, the friction properties of the Babbitt alloy deteriorate significantly. The optimized Babbitt alloy SnSb11Cu6-1.5Co was subsequently fabricated into wires, followed by conducting cold metal transfer (CMT) surfacing experiments. The Co element can promote the growth of interfacial compounds. The microstructure at the interface of the Babbitt alloy/steel is dense, and there is element diffusion between it. The metallurgical bonding is good, and there are serrated compounds relying on the diffusion layer to extend to the direction of the additive layer with serrated compounds extending and growing from the diffusion layer to the additive layer. Overall, Babbitt alloys such as SnSb11Cu6 exhibit improved comprehensive properties when containing 1.5 wt.% Co.

Experimental Analysis of the Behavior of Multiple Adhesive on the Single Lap Joint Strength

The usage of adhesively bonded lap joints in industrial applications has been growing in recent years because of the numerous advantages compared to other joining processes such as fastening, welding, and riveting. For effective design of the adhesively bonded engineering lap joints, it is essential to govern the failure potential of a particular adhesive joint under a certain load causing some stress and strain. In this work, study has been carried out by the application of multiple adhesives along the bondline region of lap joint. The objective of this paper is to experimentally examine the results of applications of single and multi-adhesives material with very different mechanical behavior along the bondline region in the single lap adhesive joint. Experimental investigations have been carried out for extracting load displacement data using tensile testing machine, Tensometer, having a capacity of 2 tonne. Multi Adhesive joint can minimize the stress concentration and improve joint strength by using different adhesive stiffness along the bondline region of lap joint and the outcome shows computable increase in the strength of the multiple adhesive bonded lap joints associated with those in which single adhesives were used over the full length of the bondline region.

Effect of heat treatment process on microstructure and properties of copper modified 1Cr11MoNiW1VNbN

Abstract The purpose of this study was to investigate the effects of Cu element content and heat treatment process on the microstructure and mechanical properties of 1Cr11MoNiW1VNbN martensitic heat-resistant steel. Microstructure was characterized by optical microscope (OM) and scanning electron microscope (SEM), tensile testing machine and impact testing machine were used to test the mechanical property. The results show that with the increase of Cu content, the precipitation of Cu-rich phase in the steel increases, while the formation of δ-ferrite and coarse carbides decreases, which significantly improves the strength of the material. When the Cu content is 2.14%, the tensile strength at 600 °C reached 542 MPa and the yield strength reached 484 MPa after normalizing at 1000 °C and tempering at 700 °C. With the increase of the normalizing temperature, the strength of the test steel decreases slightly, and the impact energy improved significantly.

Experimental and Statistical Investigations for Tensile Properties of Hemp Fibers

This study investigated the tensile behaviors of hemp fiber bundles and examined how properties including tensile strength and Young’s modulus vary with the bundle diameter. Hemp fibers were extracted, degummed, and separated into bundles of different diameters ranging from less than 50 μm to over 150 μm. Tensile tests were conducted on these fiber bundles using a rheometer-based tensile testing machine. The results showed that hemp fibers exhibited a tensile strength of 97.33 MPa and a Young’s modulus of 3.77 GPa at a 50% survival probability. However, the scale parameters for breaking stress and Young’s modulus were determined to be 620.57 MPa and 29.88 GPa, respectively. As the fiber bundle diameter increased, the tensile strength decreased significantly. This was attributed to the higher probability of defects and irregularities acting as weakness points in larger fiber bundles. In contrast, Young’s modulus (stiffness) increased with increasing bundle diameter, likely due to improved fiber–fiber interactions. To further understand the variability and reliability of the tensile properties, statistical models were developed. The Weibull distribution analysis was applied, revealing critical insights into the variability of diameter, stress at break, Young’s modulus, and strain at break. The Weibull parameters provided a comprehensive understanding of the fibers’ mechanical reliability. Additionally, the Griffith model was employed to predict the strength and Young’s modulus based on fiber diameters, supporting the observation that thinner fibers generally exhibited higher tensile strength due to fewer defects. Overall, this work highlights the importance of understanding structure–property relationships in natural fibers like hemp for optimizing their performance in composites.

Comparison of a novel side-to-side tenorrhaphy with Pulvertaft weave: an in vitro biomechanical study

PurposeThe aim of this study was to characterize the biomechanical properties of a novel side-to-side tenorrhaphy (SST), this tenorrhaphy is designed to achieve reliable strength utilizing fewer knots and greater operationalization. This is compared with a well-established tendon reconstruction technique called the Pulvertaft weave technique (PWT).MethodsTwenty fresh porcine hindfoot flexor tendons were collected, and 10 novel SST and 10 PWT were performed in each group. The repaired tendons were tested cyclically by applying a force of 35 N using an electric tensile testing machine. Tendons were loaded until they ruptured and failed. The cyclic elongation, ultimate elongation, ultimate failure load, stiffness, and operation time were recorded and analyzed for both groups, and the failure patterns of the tendons were observed.ResultsThe mean operation time were 1.86 in the SST group and 3.25 min for the PWT group, respectively. The ultimate failure load was 179.93 N ± 12.05 for the SST group and 113.46 N ± 7.89 for the PWT group. The ultimate elongation was 17.79 mm ± 0.51 for the SST group and 26.83 mm ± 0.64 for the PWT group. The stiffness of the SST group was 35.27 N/mm ± 0.90 in the SST group and 20.11 N/mm ± 0.84 in the PWT group. There was no statistically significant difference in cyclic elongation.ConclusionThe SST group performed better than the PWT group in terms of the ultimate elongation, ultimate failure load, and stiffness. It is clear that the novel SST is a reliable alternative to PWT for tendon repair. The operation time of the SST group was significantly shorter than that of the PWT group.

The addition of Bi2WO6 nanoparticles to polyvinyl alcohol film: Improvements in optical, mechanical, and electrical properties

This study deals with the influence of adding Bi2WO6 (BWO) nanoparticles on the optical, structural, dielectric, and mechanical properties of polyvinyl alcohol (PVA). BWO nanoparticles synthesized by solvothermal method were characterized by X-Ray diffraction (XRD) and scanning electron microscope (SEM-EDS). The thick film nanocomposites were analyzed by Fourier Transformed Infrared (FTIR) spectrometer, XRD device, SEM, atomic force microscope (AFM), ultraviolet visible (UV–Vis) spectrophotometer, impedance analyzer, and tensile test machine. While FTIR analyses confirmed the formation of composite structure and the presence of BWO in the composites, AFM views indicated the reduced roughness for composites. Additionally, the UV–Vis light absorption spectra revealed a narrowed band gap in the composites. Moreover, with increasing BWO contribution, gradual increases were recorded in Young's modulus, toughness and % breaking strain parameters. The frequency dependent dielectric properties was also shown that the energy storage ability of the PVA matrix enhances 25 % and 50 % due to 2 % and 3 % BWO additives, respectively. However, the composite with higher ε′ and lower ε″ values than the pure PVA in the entire frequency range was the 2 % BWO-doped nanocomposite. Based on the serious and simultaneously improvements in electrical, optical and mechanical properties, it can be suggested that 2 % BWO additive provides the opportunity to expand the application area of PVA synergistically.

Double-Chamber Underwater Thruster Diaphragm with Flexible Displacement Detection Function.

The purpose of this paper is to develop a self-detecting diaphragm integrated with a flexible sensor, which is utilized in an underwater thruster. Resistive strain sensors are easy to manufacture and integrate due to their advantages in reliable stretchability and ductility. Inspired by the structure of neurons, we fabricated resistive flexible sensors using silica gel as the matrix with carbon black and carbon nanotubes as additives. All fabricated sensors demonstrated positive resistance characteristics under 60% strain conditions, with the sensor containing a mass ratio of 9 wt % carbon black and carbon nanotubes exhibiting the best resistance-strain linearity. To verify the anti-interference capability of sensors with silica gel substrates of varying hardness values under changing environmental pressure, we tested the pressure sensitivity of the sensors by altering the hardness of the silica gel. The results indicate that silica gel with the highest hardness value provides the best resistance to environmental pressure interference. To detect the motion and deformation of the internal functional components of the thruster, we combined strain detection with the movement operation function of a silica gel diaphragm, resulting in a new integrated diaphragm with sensor detection capabilities. The integrated diaphragm was evaluated by using a tensile testing machine and an LCR tester. The results demonstrate that the mechanical properties of the diaphragm are stable, exhibiting reliable resistance characteristics and a sensitive response during underwater operation. This research can also be applied to the detection of motion amplitudes of other types of soft robots.

Study on fracture behaviour of pipeline girth welds based on curved wide plate specimens: Experimental and numerical analysis

Understanding the fracture characteristics and strain capacity of pipelines with girth welds under external loads is crucial for evaluating pipeline safety. The use of curved wide plate (CWP) specimens closely resembling full-scale (FS) pipelines in geometry provides a more realistic representation of crack tip constraint states compared to small-size fracture toughness test specimens in laboratory settings. This study aims to investigate the ductile fracture characteristics of center cracks on the outer surface of girth welds in high-grade steel pipelines under external loads through large-scale CWP tensile tests and advanced numerical simulations. Tensile tests were conducted on CWP specimens using a kiloton tensile testing machine, with double crack opening displacement (COD) gauge monitoring crack mouth opening displacement (CMOD), and high-precision displacement sensors and strain gauges tracking deformation and strains at various positions. The study yielded significant experimental results, and a finite element (FE) model of the CWP was developed using the nonlinear finite element method (FEM) to validate the experimental data against simulation results. The FE model was then used to investigate the influence of material properties on crack propagation resistance and driving force curves. A method for determining the ultimate tensile strain capacity (UTSC) of pipelines based on actual material fracture toughness was proposed. This research contributes valuable experimental data for further exploration of fracture behaviour in large-scale pipeline girth welds and offers insights for safety evaluations of such welds.

The fracture and perforation failure analysis of downhole tubes

：The downhole tubes were fractured and perforated after 5 years of shut-in due to high water cuts. This study employs a comprehensive array of analytical techniques to investigate the mechanisms behind fractures and perforations. Utilizing non-destructive testing (NDT), direct reading spectrometer, tensile strength testing machine, impact testing machine, optical microscope (OM), macroscopic fracture morphology observation, scanning electron microscope (SEM) and energy spectrum analysis (EDS), and sulfide stress corrosion cracking (SSCC) was studied. The reason for the fracture of the tubing is that under the condition of low pH value, high hydrogen sulfide environment, the tubing is fractured due to stress concentration caused by cracks in the outer thread relief groove. The perforation of the inner tube wall was caused by gradual wall thickness reduction under the influence of H2S, CO2, and Cl−, resulting in fouling and eventual perforation. To prevent tube corrosion during long-term shut-in, it is recommended to inject crude oil or diesel into the well.

Influence of Ageing Treatment on Microstructure and Mechanical Properties of GH4169 Alloy Prepared Using Wire Arc Additive Manufacturing

The effects of solid-solution and ageing treatments on the microstructure and mechanical properties of a GH4169 alloy made by wire arc additive manufacturing, micro-casting, and forging were researched. The microstructure, along with the size and type of precipitated phase, were analysed using an optical microscope, scanning electron microscope, and transmission electron microscope. The strength and toughness were tested using a tensile testing machine. The results show that a polygonal austenite microstructure was obtained for the GH4169 alloy prepared through wire arc additive manufacturing, micro-casting, and forging, followed by solid-solution and double-ageing treatments at different times. There were a few twins in the austenite matrix. A large number of nano-sized γ″- and γ′-precipitated phases and a small number of Laves phases and MX phases were found in the matrix. The tensile strength and yield strength of the GH4169 alloy increased first and then decreased with the ageing time. After ageing for 16 h, the maximum yield strength was 1287 ± 22 MPa, the maximum tensile strength was 1447 ± 19 MPa, and the elongation was about 19.5%. The main strength mechanism is precipitated phase strength and solid-solution strength. The fracture exhibited obvious ductile fracture characteristics.

Effect of cooling temperature on microstructure and mechanical properties of Nb microalloyed hot-rolled rebar

In this study, the Gleeble-3800 thermal simulation tester was used to simulate various cooling temperature processes for two groups of rebar. Then, the microstructure, precipitation, and mechanical properties of the rebars were characterized using SEM (scanning electron microscopy), EBSD (electron backscatter diffraction), HRTEM (high resolution transmission electron microscopy), and MST810 (universal tensile testing machine). The effect of cooling temperature on the microstructure and mechanical properties was systematically investigated. The results showed that reducing the cooling temperature from 750 °C to 600 °C decreased the ferrite grain size in 0.032 wt % Nb rebar to 7.03 ± 1.5 μm, compared to the 0 wt% Nb rebar. In addition, the pearlite lamellar spacing was refined to 0.103 ± 0.5 μm, and the average particle size of elliptical Nb-rich composite carbides was 9 nm. The tensile strength and yield strength reached 795 ± 9 MPa and 638 ± 8 MPa, respectively, with an elongation after fracture of 17.78 ± 1.0 %. The fracture surface exhibited a dimple morphology.

Stiffness in compression therapy: Analytical estimation of pressure changes beneath textile compression devices

Compression pressure changes in dynamic conditions under textile compression devices have a critical impact on the success of compression therapy. Models exist to predict the level of compression pressure, but not the actual change in pressure. This paper aims to derive a formula to accurately determine the pressure change under textile compression devices, to investigate the factors influencing the pressure change and to verify their effects through theoretical analysis. Firstly, a formula based on Laplace’s law is presented which mathematically describes the dependencies of pressure changes. Secondly, a simulation is carried out to demonstrate the effect of these dependencies on pressure changes using theoretical textile curve functions. Finally, the effect of these dependencies is demonstrated by testing short- and long-stretch bandages in a tensile testing machine and using the recorded material curves to simulate a theoretical application of these bandages to the lower limbs. The results show that the change in pressure is not solely determined by the intrinsic properties of the material, but is influenced by several variables, including the mechanical performance of the textile materials during stretching, the target pressures for application of the textile material, and the body geometries to which the material is applied. Pressure change cannot be a constant for textile compression devices such as bandages. The research increases the understanding of the factors that influence pressure changes in compression device materials. The findings may have implications for the design and selection of compression textiles in clinical applications.

Optimization of TIG welding parameters for tensile load testing on dissimilar material joints of galvanized steel (SGCC) and low carbon steel (SPCC-SD)

Tungsten Inert Gas (TIG) welding uses a tungsten electrode and argon or helium gas for shielding. It offers excellent shielding, stable arc, adjustable heat input, minimal spattering, and attractive welds. Widely used in various industries, especially for thin materials like galvanized sheets, TIG welding can be challenging for dissimilar materials like galvanized steel and low-carbon steel due to their different melting points. Studying optimal welding parameters is crucial for success. This research focuses on TIG welding of SPCC-SD (JIS 3141) and SGCC (JIS 3302) materials with thicknesses of 0.6 mm and 0.8 mm. The electric current was varied at 45, 50, and 55 A, whereas the gas flow rate was varied at 12, 15, and 18 LPM. The weld bead diameter was varied as 5, 8, and 10 mm. Subsequently, the welded samples were subjected to tensile testing using a SHIMADZU AGS-X 10Kn STD E200V tensile testing machine. The data from the tensile tests were analysed using S/N ratio analysis and Analysis of Variance (ANOVA) with the assistance of the Minitab software. The results of the S/N ratio analysis indicated that the most optimal parameters were an electric current of 55 A, flow rate of 15 LPM, and weld bead diameter of 10 mm. Conversely, the ANOVA revealed that the weld bead diameter significantly influenced the tensile load in TIG welding of SPCC-SD (JIS 3141) with SGCC (JIS 3302) materials, accounting for up to 44.42% of the variation. Following the weld bead diameter, the flow rate and welding current contributed to 21.93% and 16.41%, respectively.

Effect of Low-Temperature Tempering Temperature on the Mechanical Properties of NM500 Wear-Resistant Steel

Abstract In order to explore the effect of low temperature tempering heat treatment temperatures on Brinell hardness (HB), impact absorption energy (KV2) and tensile mechanical properties of NM500 wear-resistant steel, isothermal tempering heat treatment of NM500 wear-resistant steel sheets after quenching were carried out at 200~260 °C. The microstructures, Brinell hardness, -20 °C impact energies and tensile mechanical properties of NM500 wear-resistant steel after tempered were analyzed by optical microscope, Brinell hardness tester, pendulum impact testing machine and tensile testing machine respectively. The results show that when the tempering temperature increases from 200 °C to 260 °C, the Brinell hardness of NM500 wear-resistant steel decreases from 490 HBW to 460 HBW, the offset yield strength (Rp0.2) decreases from 1396.3MPa to 1351.0MPa, and the tensile strength (Rm) decreases from 1708.5 MPa to 1615.0 MPa. However, the low temperature tempering temperature has no significant effect on the microstructure and elongation after fracture. According to GB/T 24186-2022, 200~220 °C is the suitable low temperature tempering temperature range for NM500 wear-resistant steel.

A good balance between the efficiency of ionizing radiation shielding and mechanical performance of various tin-based alloys: Comparative analysis

The Sn-Bix (x = 30, 40, 50, 60 and 70%) radiation shielding alloys were prepared using a melting process of the alloying material in a ceramic crucible at 200 °C for 120 min. The structural characterization for synthesized samples was carried out using X-ray Diffraction technique (XRD). The hardness and elastic properties of the prepared alloys was measured using micro-indentation creep technology and tensile test machine respectively. XRD pattern indicated that that the crystal size of Sn phase is lowered by increasing Bi concentration in the Sn matrix. The hardness decreases as the dwell time increases. The hardness values and elastic properties (in terms of young modulus) were significantly improved due to the decrease in the crystallite size by increasing Bi content. The stress exponent (n) value increase by increasing Bi content which mean that the mechanical properties improved due to increment of resistance. Furthermore, the produced alloys' nuclear shielding ability was investigated. The μm values were calculated using MCNP simulation code and XCOM software over a broad energy range of 0.015 MeV–15 MeV with good agreement between them. Several characteristics are estimated in order to properly understand the researched alloy's radiation and properties of neutron shielding. The findings showed that a higher Bi concentration causes the crystal size to decrease, improving the radiation shielding and mechanical qualities. The alloy Sn-70% Bi has a maximum increase of vicker hardness, tensile strength, and young's modulus. The findings of the shielding parameters indicate that the alloys under study are efficient gamma shielding materials in contrast to other typical shielding materials and materials that have been examined recently. The highest mechanical efficiency and rather strong gamma-ray shielding capabilities are found in the Sn–70Bi alloy. Owing to its ability to effectively balance mechanical performance and shielding, the Sn–70Bi are approved for use in radiation protection. In addition, when compared to all other manufactured alloys, typical neutron shielding materials, and recently investigated materials, the results further demonstrate that the Sn–70Bi alloy has the best neutron attenuation capability. Furthermore, in terms of mass stopping power (MSP) and projected range (PR), the Sn–70Bi alloy demonstrates the most effective attenuation for alpha particles (He+2) and protons (H+1). These results imply that the Sn–70Bi alloy provide superior mechanical performance and nuclear shielding for a range of applications including industrial, medicinal, and nuclear waste storage in the future.

Low temperature tensile behavior and microstructure analysis of copper containing antibacterial stainless steel

Using Shimadzu AGS-100KN universal tensile testing machine, tensile tests were conducted on copper containing antibacterial stainless steel at 25 °C, −20 °C, −60 °C, −100 °C, and −140 °C. The fracture morphology and microstructure evolution of the material were then analyzed using various techniques including scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), X-ray diffraction (XRD), and transmission electron microscopy (TEM) techniques. The experimental findings showed that with the decrease of deformation temperature, the ultimate tensile strength(UTS) increased by about 49.7 %, the yield strength (YS) increased by about 35.5 %, and the elongation(EI) decreased by about 27.3 %, showed obvious low temperature strengthening effect. The High-angle grain boundaries (HAGBs) increased with decreasing temperature, while low-angle grain boundaries (LAGBs) decreased. The plasticity gradually decreased and the strength gradually increased, resulting in an increase in its ability to resist deformation. The number of precipitated phases gradually increased, and the size also gradually becomes larger, and the interaction between the diffusely distributed precipitated phases and dislocations led to precipitation strengthening. With the decrease of temperature, the stacking fault energy gradually decreased, the SFE was 21.26 mJ/m2 at the temperature of −140 °C. The main plastic deformation mechanism of copper-containing austenitic stainless steel in the low-temperature tensile process was transformed from deformation twins to strain-induced martensitic phase transformation.

Presoaking hamstring autograft with vancomycin does not jeopardize its biomechanical properties, including graft elongation, after cyclic loading.

Presoaking the graft with vancomycin before implantation has been shown to reduce the risk of postoperative infection after anterior cruciate ligament reconstruction (ACLR). However, the effects of presoaking on the graft biomechanical properties remain unclear. This study aimed to determine whether presoaking the graft with vancomycin affects the graft biomechanical properties and length after cyclic loading. Ten paired (20 specimens) gracilis and semitendinous tendons were harvested from fresh-frozen human cadaveric specimens. Two tendons were folded in half to make four strands, and the grafts were randomized into the vancomycin and control groups. The graft was exposed to the antibiotic solution for 15 min (5 mg/mL) and prepared by mixing 1 g of vancomycin with 200 mL of normal saline (NaCl 0.9%). The control group was soaked in normal saline for 15 min. The prepared grafts were attached to the actuator of a dynamic tensile-testing machine. All grafts were tested with 3000 cycles of cyclic loading followed by a pull-to-failure. The cyclic loading protocol consisted of position and load control blocks to simulate the graft in vivo in the postoperative phase after ACLR. Presoaking in vancomycin did not jeopardize the biomechanical properties of the graft. In addition, presoaking with vancomycin did not elongate the grafts. No significant differences were found in the mean Young's modulus and the mean total elongation of the graft of the specimen between the vancomycin group and the control group. Presoaking the graft with vancomycin jeopardized neither its biomechanical properties nor elongation even after cyclic loading in this in vitro study. It is suggested that vancomycin presoaking could be considered a safe and effective preventive measure for postoperative infections after ACLR. Not applicable.

Synthesis and properties of silicone-modified polyurethane acrylate for magnetically driven blue light photocurable superhydrophobic coatings

A low surface energy silicone-modified polyurethane acrylate (Si-PUA) has been synthesized and employed as the primary constituent for the magnetically driven photocurable coatings. By integrating magnetically driven assembly technology with blue light photocuring technology, a superhydrophobic coating featuring low surface energy and micro/nano rough structures was successfully fabricated. The influences of hydroxy-terminated polydimethylsiloxane (PDMS) content and the R-value (-NCO/-OH) on the performance of PUA and coating systems were investigated using Photo-DSC, TGA, rheology, tensile testing machine, and SEM-EDS. The molecular structure of Si-PUA was characterized using FT-IR and 1HNMR. The result revealed that the composite coating exhibited a minimum surface energy when the PDMS content was 5 wt% and the R-value was 1.6, resulting in a surface free energy of 24 mJ/m2. When the coating formulation consists of a Si-PUA:HEA ratio of 7:3, an initiator dosage of 2% (with CQ/EDB at a 1:1 ratio), and a carbonyl iron powder (CIP) content of 100 wt%, the resulting photocured film exhibits a surface contact angle of 157.6° and a rolling angle of 5°, thereby satisfying the superhydrophobicity standard.

Pengaruh Perbedaan Ayunan Pengelasan Dengan Metode SMAW Terhadap Kekuatan Tarik Pada Baja ST 37 Strip 5 MM

The purpose of this study was to see the effect of differences in welding swing on the tensile strength of 5 mm strip iron. The number of research samples was 6 pieces divided into two groups, the first group of 3 pieces welded with zig-zag welding swing, the second group of 3 pieces welded with spiral welding swing. The tensile test object used a tensile testing machine to determine the tensile stress value of the welding swing of each test object by slowly applying a load or force until the test object broke. This research method uses quantitative with a comparative experimental approach. The results of the welding tensile stress test of each test object sample welded with zig-zag and spiral welding swing joints showed that there was a similarity in the tensile test data, namely normal distribution, and similarity in variance. Hypothesis testing was obtained from the results of the tensile stress test of SMAW welding results with zig-zag and spiral welding swings showing a Tcount value of -8.021 (dk) = n1 + n2-2 at a significance level of 0.01 or 1%, a Ttable of 4.604 was obtained. So that the magnitude of the tensile stress of SMAW welding results with zig-zag and spiral welding swings has no significant influence.