CHARACTERIZATION OF ULTRASONIC ASSISTED ADHESIVE JOINTS

Joining experiments using different adhesives were carried out. In addition to the adhesive, the specimens were also treated with ultrasonic waves to improve the load carrying capacity of the joined parts. Lap joint shear tests have been conducted to quantify this improvement.

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Characterization of Friction Stir Welding on Aluminum

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.68.167 ◽

2009 ◽

Vol 68 ◽

pp. 167-174 ◽

Cited By ~ 1

Author(s):

Jerry Wong ◽

Patricia del C. Zambrano ◽

Martha Patrizia Guerrero-Mata ◽

Victor Mucino ◽

Rafael Colás

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Carrying Capacity ◽

Feeding Rate ◽

Load Carrying Capacity ◽

Rotating Speed ◽

Friction Stir ◽

Load Carrying ◽

Scanning Electron

A series of linear and spot stir welding friction tests were carried out on aluminum samples of 1 mm in thickness and area of 100 mm x 27 mm. The tool rotating speed was varied from 2000 to 4000 RPM and the feeding rate from 45 to 67.8 mm/min. The temperature distribution during welding was measured by thermocouples inserted within the aluminum strips. The microstructure of the welded nuggets and the HAZ were analyzed by optical and scanning electron microscopy. Some samples were tested intension to measure the load carrying capacity of the welded bead. Preliminary analyses indicate that the temperature at the heat affected zone increases with the rotating speed.

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Effect of joint stiffness and size on stability of three-way single-layer cylindrical reticular shell

International Journal of Space Structures ◽

10.1177/0956059920931019 ◽

2020 ◽

Vol 35 (3) ◽

pp. 90-107

Author(s):

Hui-jun Li ◽

Yoshiya Taniguchi

Keyword(s):

Carrying Capacity ◽

Joint Stiffness ◽

Single Layer ◽

Shear Stiffness ◽

Limit Load ◽

Torsional Stiffness ◽

Axial Stiffness ◽

Load Carrying Capacity ◽

Load Carrying ◽

Joint Shear

The main aim of the present article is to study the effect of joint stiffness and joint size on load-carrying capacity of single-layer cylindrical reticular shell. One normalized joint bending stiffness index κb and three proposed normalized indexes, that is, normalized joint axial stiffness κa, normalized joint shear stiffness κs, and normalized joint torsional stiffness κt, are used to evaluate the stiffness of joint. Through a large number of numerical computations, the main conclusions are summarized as follows: κb has a significant effect on limit load of reticular shell, and this effect has a close relationship to rise-to-span ratio of reticular shell. If κb is larger than 30, the joint can be treated as rigid joint. The relationship between the logarithm of κb and limit load of reticular shell can be expressed by the logistic formulation. Overall rigidity and load-carrying capacity of reticular shell are greatly influenced by joint axial stiffness. If κa is larger than 30, the effect of joint axial stiffness on load-carrying capacity of reticular shell is no longer obvious. Otherwise, the load-carrying capacity will be markedly reduced. The relation between the logarithm of κa and limit load of reticular shell can be fitted by the Dose–response formulation. The load-carrying capacity of reticular shell is also influenced by joint torsional stiffness and joint shear stiffness to some extent. The relation between the logarithm of κs and limit load can be fitted by the Asymptotic formulation. The effect of joint size on overall rigidity and limit load of reticular shell is evident and cannot be neglected. The limit load gradually decreases with the decrease in joint size, and there is an approximate linear relationship between limit load and joint size.

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Strength Calculation and Equal Load-Carrying-Capacity Design of an Undermatched HSLA Lap Joint under Out-of-Plane Bending

Metals ◽

10.3390/met11010161 ◽

2021 ◽

Vol 11 (1) ◽

pp. 161

Author(s):

Junli Guo ◽

Zhibo Dong ◽

Hongyuan Fang ◽

Jiajie Wang

Keyword(s):

Carrying Capacity ◽

Calculation Method ◽

Design Method ◽

Strength Calculation ◽

Weld Strength ◽

Load Carrying Capacity ◽

Lap Joint ◽

Load Carrying ◽

Out Of Plane ◽

Plane Bending

This work aimed to design an undermatched lap joint that has an equal load-carrying capacity (ELCC) with a traditional equalmatched joint under out-of-plane bending. A weld strength calculation method was proposed based on the similarity of a lap joint and a T joint, as shown using linear elastic finite element (FE) analysis, and then applied in the analysis of a lap joint and the design of an ELCC lap joint. A single lap joint of HQ785 steel was chosen for experimental verification. The bending force limit of the ELCC joint was 93.35% of the theoretical prediction and 96.90% of the traditional equalmatched joint. The results show that the weld strength calculation method and the ELCC design method are reasonable and feasible.

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Micro/nanomechanical and tribological characterization of ultrathin amorphous carbon coatings

Journal of Materials Research ◽

10.1557/jmr.1999.0309 ◽

1999 ◽

Vol 14 (6) ◽

pp. 2328-2337 ◽

Cited By ~ 100

Author(s):

Xiaodong Li ◽

Bharat Bhushan

Keyword(s):

Wear Resistance ◽

Amorphous Carbon ◽

Carrying Capacity ◽

Load Carrying Capacity ◽

Carbon Coatings ◽

Load Carrying ◽

Tribological Characterization ◽

Thick Coatings ◽

Amorphous Carbon Coatings

Micro/nanomechanical and tribological characterization of ultrathin amorphous carbon coatings, deposited by filtered cathodic arc (FCA), direct ion beam (IB), electron cyclotron resonance plasma chemical vapor deposition (ECR-CVD), and sputter (SP) deposition processes on Si substrate have been conducted using a nanoindenter with a nanoscratch attachment and an accelerated ball-on-flat tribometer. Coating thicknesses of 20, 10, 5 nm and, for the first time, 3.5 nm coatings have been investigated. It was found the FCA coating exhibits the highest hardness and elastic modulus, followed by the ECR-CVD, IB, and SP coatings. In general, the thicker coatings exhibited better scratch/wear performance than the thinner coatings due to their better load-carrying capacity as compared to the thinner coatings. At 20 nm, the FCA and ECR-CVD coatings show the best scratch and wear resistance, while the IB and ECR-CVD coatings show the best scratch and wear resistance at 10 nm. Five nanometer thick coatings show reasonable scratch and wear resistance, while 3.5 nm thick coatings show extremely low load-carrying capacity and poor scratch and wear resistance. It appears that the 3.5 nm coatings studied are unfeasible for scratch and wear resistance applications as of now.

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Failure of Thin Film Lubrication—An Expedient for the Characterization of Lubricants

Journal of Lubrication Technology ◽

10.1115/1.3251718 ◽

1981 ◽

Vol 103 (4) ◽

pp. 497-501 ◽

Cited By ~ 12

Author(s):

B. J. Tabor

Keyword(s):

Thin Film ◽

Chemical Composition ◽

Bulk Viscosity ◽

Carrying Capacity ◽

Empirical Relation ◽

Load Carrying Capacity ◽

Thin Film Lubrication ◽

Load Carrying ◽

Film Lubrication

A method has been developed to characterize lubricants, starting from the failure of thin film lubrication in sliding concentrated steel contacts. For a number of lubricants, differing in viscosity and chemical composition, the collapse of the partial EHD film is taken as a criterion of the lubrication behavior. The contribution of viscosity and chemical composition of lubricants to the load carrying capacity of the partial EHD film at a speed of 1 m/s (P1) can be separated. This is achieved by plotting the value P1 as a function of the logarithm of the bulk viscosity (η). The following linear empirical relation P1 = β log η + α is found to be valid within the viscosity range of 2–200 • 10−3 Pa.s. Lubricants with the same chemical composition have an equal value of α.

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Influence of Yield Strength Variability over Cross-Section to Steel Beam Load-Carrying Capacity

Nonlinear Analysis Modelling and Control ◽

10.15388/na.2005.10.2.15129 ◽

2005 ◽

Vol 10 (2) ◽

pp. 151-160 ◽

Cited By ~ 3

Author(s):

J. Kala ◽

Z. Kala

Keyword(s):

Yield Strength ◽

Cross Section ◽

Carrying Capacity ◽

Bending Moment ◽

Statistical Characteristics ◽

Load Carrying Capacity ◽

Load Carrying ◽

Strength Variability ◽

Hot Rolled ◽

Hot Rolled Steel

Authors of article analysed influence of variability of yield strength over cross-section of hot rolled steel member to its load-carrying capacity. In calculation models, the yield strength is usually taken as constant. But yield strength of a steel hot-rolled beam is generally a random quantity. Not only the whole beam but also its parts have slightly different material characteristics. According to the results of more accurate measurements, the statistical characteristics of the material taken from various cross-section points (e.g. from a web and a flange) are, however, more or less different. This variation is described by one dimensional random field. The load-carrying capacity of the beam IPE300 under bending moment at its ends with the lateral buckling influence included is analysed, nondimensional slenderness according to EC3 is λ¯ = 0.6. For this relatively low slender beam the influence of the yield strength on the load-carrying capacity is large. Also the influence of all the other imperfections as accurately as possible, the load-carrying capacity was determined by geometrically and materially nonlinear solution of very accurate FEM model by the ANSYS programme.

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Fuzzy Sets Theory in Comparison with Stochastic Methods to Analyse Nonlinear Behaviour of a Steel Member under Compression

Nonlinear Analysis Modelling and Control ◽

10.15388/na.2005.10.1.15135 ◽

2005 ◽

Vol 10 (1) ◽

pp. 65-75 ◽

Cited By ~ 5

Author(s):

Z. Kala

Keyword(s):

Fuzzy Sets ◽

Carrying Capacity ◽

Stochastic Methods ◽

Nonlinear Behaviour ◽

Load Carrying Capacity ◽

Load Carrying ◽

Input Parameters ◽

Stochastic Solution ◽

Fuzzy Solution ◽

Sets Theory

The load-carrying capacity of the member with imperfections under axial compression is analysed in the present paper. The study is divided into two parts: (i) in the first one, the input parameters are considered to be random numbers (with distribution of probability functions obtained from experimental results and/or tolerance standard), while (ii) in the other one, the input parameters are considered to be fuzzy numbers (with membership functions). The load-carrying capacity was calculated by geometrical nonlinear solution of a beam by means of the finite element method. In the case (ii), the membership function was determined by applying the fuzzy sets, whereas in the case (i), the distribution probability function of load-carrying capacity was determined. For (i) stochastic solution, the numerical simulation Monte Carlo method was applied, whereas for (ii) fuzzy solution, the method of the so-called α cuts was applied. The design load-carrying capacity was determined according to the EC3 and EN1990 standards. The results of the fuzzy, stochastic and deterministic analyses are compared in the concluding part of the paper.

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Pavement Damage Due to Conventional and New Generation of Wide-Base Super Single Tires

Tire Science and Technology ◽

10.2346/1.2174344 ◽

2005 ◽

Vol 33 (4) ◽

pp. 210-226 ◽

Cited By ~ 6

Author(s):

I. L. Al-Qadi ◽

M. A. Elseifi ◽

P. J. Yoo ◽

I. Janajreh

Keyword(s):

Carrying Capacity ◽

Material Properties ◽

Three Dimensional ◽

Fe Analysis ◽

Load Carrying Capacity ◽

Inflation Pressure ◽

3D Finite Element ◽

Load Carrying ◽

Pavement Damage ◽

New Generation

Abstract The objective of this study was to quantify pavement damage due to a conventional (385/65R22.5) and a new generation of wide-base (445/50R22.5) tires using three-dimensional (3D) finite element (FE) analysis. The investigated new generation of wide-base tires has wider treads and greater load-carrying capacity than the conventional wide-base tire. In addition, the contact patch is less sensitive to loading and is especially designed to operate at 690kPa inflation pressure at 121km/hr speed for full load of 151kN tandem axle. The developed FE models simulated the tread sizes and applicable contact pressure for each tread and utilized laboratory-measured pavement material properties. In addition, the models were calibrated and properly validated using field-measured stresses and strains. Comparison was established between the two wide-base tire types and the dual-tire assembly. Results indicated that the 445/50R22.5 wide-base tire would cause more fatigue damage, approximately the same rutting damage and less surface-initiated top-down cracking than the conventional dual-tire assembly. On the other hand, the conventional 385/65R22.5 wide-base tire, which was introduced more than two decades ago, caused the most damage.

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