A Study on the Hysteretic Characteristics of Hybrid Steel Damper System Using the High Ductile Low-Yield-Point Steel

This paper supposes a S-shape low yield steel damper. Based on the mechanical behaviors of the damper, its analytical model is established. Meanwhile, the damper’s hysteretic characteristics are numerically simulated by the FEM ABAQUS to obtain the main mechanical parameters of this damper. These parameters are compared with the results from the established analytical model. Results indicate that the analytical model is a-greeable to the FEM analysis. In addition, Analytical results also show that the S-shape low yield damper pos-sesses superior mechanical behaviors and hysteretic characteristics to fit extremely for mitigating the vibrationof engineering structures.

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Analysis on Deformation Behavior of High Strength Steel using the Finite Element Method in Conjunction with Constitutive Model Considering Elongation at Yield Point

Korean Journal of Metals and Materials ◽

10.3365/kjmm.2010.48.07.598 ◽

2010 ◽

Vol 48 (7) ◽

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Constitutive Model ◽

Yield Point ◽

High Strength Steel ◽

Deformation Behavior ◽

High Strength ◽

The Finite Element Method ◽

Element Method

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Study of the character and causes of destruction of the cardan shaft of the propeller engine

Industrial laboratory Diagnostics of materials ◽

10.26896/1028-6861-2019-85-12-43-50 ◽

2019 ◽

Vol 85 (12) ◽

pp. 43-50

Author(s):

D. A. Movenko ◽

L. V. Morozova ◽

S. V. Shurtakov

Keyword(s):

Mechanical Properties ◽

Chemical Composition ◽

Yield Point ◽

Protective Coating ◽

Fracture Pattern ◽

Corrosion Cracking ◽

Tempered Martensite ◽

Neck Formation ◽

Static Mechanism ◽

Shaft Surface

The results of studying operational destruction of a high-loaded cardan shaft of the propeller engine made of steel 38KhN3MFA are presented to elucidate the cause of damage and develop a set of recommendations and measures aimed at elimination of adverse factors. Methods of scanning electron and optical microscopy, as well as X-ray spectral microanalysis are used to determine the mechanical properties, chemical composition, microstructure, and fracture pattern of cardan shaft fragments. It is shown that the mechanical properties and chemical composition of the material correspond to the requirements of the regulatory documentation, defects of metallurgical origin both in the shaft metal and in the fractures are absent. The microstructure of the studied shaft fragments is tempered martensite. Fractographic analysis revealed that the destruction of cardan shaft occurred by a static mechanism. The fracture surface is coated with corrosion products. The revealed cracks developed by the mechanism of corrosion cracking due to violation of the protective coating on the shaft. The results of the study showed that the destruction of the cardan shaft of a propeller engine made of steel 38Kh3MFA occurred due to formation and development of spiral cracks by the mechanism of stress corrosion cracking under loads below the yield point of steel. The reason for «neck» formation upon destruction of the shaft fragment is attributed to the yield point of steel attained during operation. Regular preventive inspections are recommended to assess the safety of the protective coating on the shaft surface to exclude formation and development of corrosion cracks.

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REPUBLIC 65

Alloy Digest ◽

10.31399/asm.ad.sa0098 ◽

1960 ◽

Vol 9 (5) ◽

Keyword(s):

Heat Treatment ◽

Corrosion Resistance ◽

Tensile Properties ◽

Yield Point ◽

Precipitation Hardening ◽

Heat Treating ◽

Low Alloy Steel ◽

Rolled Condition ◽

Hardening Heat Treatment ◽

Minimum Yield

Abstract REPUBLIC-65 is a precipitation hardenable low alloy steel which will meet 65000 psi minimum yield point in the as-rolled condition followed by a precipitation hardening heat treatment. This datasheet provides information on composition, hardness, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: SA-98. Producer or source: Republic Steel Corporation.

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Effect of Pressure Distribution on the Energy Dissipation of Lap Joints under Equal Pre-tension Force

Open Physics ◽

10.1515/phys-2019-0034 ◽

2019 ◽

Vol 17 (1) ◽

pp. 320-328

Author(s):

Delin Sun ◽

Minggao Zhu

Keyword(s):

Energy Dissipation ◽

Pressure Distribution ◽

Theoretical Basis ◽

Lap Joints ◽

Power Exponent ◽

Lap Joint ◽

Stick Slip ◽

Pressure Distributions ◽

Hysteretic Characteristics ◽

Effective Use

Abstract In this paper, the energy dissipation in a bolted lap joint is studied using a continuum microslip model. Five contact pressure distributions compliant with the power law are considered, and all of them have equal pretension forces. The effects of different pressure distributions on the interface stick-slip transitions and hysteretic characteristics are presented. The calculation formulation of the energy dissipation is introduced. The energy dissipation results are plotted on linear and log-log coordinates to investigate the effect of the pressure distribution on the energy distribution. It is shown that the energy dissipations of the lap joints are related to the minimum pressure in the overlapped area, the size of the contact area and the value of the power exponent. The work provides a theoretical basis for further effective use of the joint energy dissipation.

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A Model for the Elastoplastic Behavior of Isotactic Poly(propylene) Below the Yield Point

Macromolecular Materials and Engineering ◽

10.1002/mame.200390009 ◽

2003 ◽

Vol 288 (2) ◽

pp. 164-174 ◽

Cited By ~ 4

Author(s):

Aleksey D. Drozdov ◽

Jesper deC. Christiansen

Keyword(s):

Yield Point ◽

Elastoplastic Behavior ◽

Poly Propylene

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A Comprehensive Study on the Optimal Design of Magnetorheological Dampers for Improved Damping Capacity and Dynamical Adjustability

Actuators ◽

10.3390/act10030064 ◽

2021 ◽

Vol 10 (3) ◽

pp. 64

Author(s):

Liankang Wei ◽

Hongzhan Lv ◽

Kehang Yang ◽

Weiguang Ma ◽

Junzheng Wang ◽

...

Keyword(s):

Optimal Design ◽

Optimization Methods ◽

Design Stage ◽

Damping Capacity ◽

Damping Force ◽

Simulation And Optimization ◽

Damping Characteristics ◽

Hysteretic Characteristics ◽

Gap Width ◽

Comprehensive Study

Purpose: We aim to provide a systematic methodology for the optimal design of MRD for improved damping capacity and dynamical adjustability in performing its damping function. Methods: A modified Bingham model is employed to model and simulate the MRD considering the MR fluid’s compressibility. The parameters that describe the structure of MRD and the property of the fluid are systematically examined for their contributions to the damping capacity and dynamically adjustability. A response surface method is employed to optimize the damping force and dynamically adjustable coefficient for a more practical setting related to the parameters. Results: The simulation system effectively shows the hysteretic characteristics of MRDs and shows our common sense understanding that the damping gap width and yoke diameter have significant effects on the damping characteristics of MRD. By taking a typical MRD device setup, optimal design shows an increase of the damping force by 33% and an increase of the dynamically adjustable coefficient by 17%. It is also shown that the methodology is applicable to other types of MDR devices. Conclusion: The compressibility of MR fluid is one of the main reasons for the hysteretic characteristics of MRD. The proposed simulation and optimization methods can effectively improve the MRD’s damping performance in the design stage.

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