EVALUATION OF DAMAGE IN STEELS SUBJECTED TO EXPLOITATION LOADING - DESTRUCTIVE AND NON-DESTRUCTIVE METHODS

Damage due to creep and plastic flow is assessed using destructive and non-destructive methods in steels (40HNMA and P91). In the destructive methods the standard tension tests were carried out after prestraining and variations of the selected tension parameters were taken into account for damage identification. In order to assess a damage development during the creep and plastic deformation the tests for both steels were interrupted for a range of the selected strain magnitudes. The ultrasonic and magnetic techniques were used as the non-destructive methods for damage evaluation. The last step of the experimental programme contained microscopic observations. A very promising correlation between parameters of methods for damage development evaluation was achieved. It is well proved for the ultimate tensile stress and birefringence coefficient.

Download Full-text

EVALUATION OF DAMAGE DEVELOPMENT IN STEELS SUBJECTED TO PRIOR DEFORMATION: DESTRUCTIVE AND NONDESTRUCTIVE TECHNIQUES

Journal of Multiscale Modelling ◽

10.1142/s1756973709000219 ◽

2009 ◽

Vol 01 (03n04) ◽

pp. 479-499 ◽

Cited By ~ 4

Author(s):

ZBIGNIEW L. KOWALEWSKI ◽

SŁAWOMIR MACKIEWICZ ◽

JACEK SZELĄŻEK ◽

KRYSTYNA PIETRZAK ◽

BOLESŁAW AUGUSTYNIAK

Keyword(s):

Plastic Deformation ◽

Elevated Temperatures ◽

Damage Identification ◽

Creep Damage ◽

Damage Evaluation ◽

Material Degradation ◽

Damage Development ◽

Nondestructive Methods ◽

Tension Tests ◽

Magnetic Techniques

Creep damage due to constant loading at elevated temperatures and damage due to plastic deformation at room temperature are assessed using destructive and nondestructive methods in steels (40HNMA and P91). In the destructive methods the standard tension tests were carried out after prestraining and variations of the selected tension parameters were taken into account for damage identification. In order to assess damage development during the creep and plastic deformation the tests for both steels were interrupted for a range of selected strain magnitudes. Ultrasonic and magnetic techniques were used as the nondestructive methods for damage evaluation. The last step of the experimental programme contained microscopic observations. The results show that ultrasonic and magnetic parameters can be good indicators of material degradation and can help to locate the regions where material properties are changed due to prestraining. A good correlation of mechanical and selected nondestructive parameters identifying damage was achieved for both tested steels.

Download Full-text

Destructive and Ultrasonic Investigations of Damage Development in Metallic Materials

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.340-341.229 ◽

2007 ◽

Vol 340-341 ◽

pp. 229-234 ◽

Cited By ~ 3

Author(s):

Zbigniew L. Kowalewski ◽

Sławomir Mackiewicz ◽

Jacek Szelażek

Keyword(s):

Power Plants ◽

Elevated Temperatures ◽

Damage Identification ◽

Damage Development ◽

Damage Degree ◽

Yield Loci ◽

Development Evaluation ◽

Non Destructive ◽

Destructive Methods

Damage development due to creep under uniaxial tension at elevated temperatures is assessed using destructive and non-destructive methods in steels, commonly used in power plants or chemical industry, and in aluminium alloy used in aircrafts for responsible elements. The results obtained using two different destructive methods for assessments of damage development are critically discussed. In the first method the specimens of steel after different amounts of creep prestraining were stretched up to failure and variations of the selected tension parameters were taken into account for damage identification. In the second one, a damage degree was evaluated by studying variations of an initial yield locus position in the stress space and by determination of the yield loci dimensions. The ultrasonic investigations were selected as the non-destructive method for damage development evaluation.

Download Full-text

Observation of Three Dimensional Magnetic Fields of Tool Steel (JIS-SKS93) around Vicker's Indentations

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.372.265 ◽

2013 ◽

Vol 372 ◽

pp. 265-269

Author(s):

Katsuyuki Kida ◽

Takashi Honda

Keyword(s):

Plastic Deformation ◽

Magnetic Fields ◽

Crack Growth ◽

Tool Steel ◽

Three Dimensional ◽

Hall Probe ◽

Probe Microscope ◽

Non Destructive ◽

The Magnetic Field ◽

Destructive Methods

Crack growth under cyclic loading causes failure of machine components. Non-destructive methods that can be related to plastic deformation around crack tip are necessary to study the crack growth. In the present work, a scanning Hall probe microscope (SHPM) equipped with GaAs film sensors was used to observe the magnetic fields around the plastic deformation induced by Vicker's indentations in tool steel specimens (SKS93, JIS B 4404: 2006, equivalent to AISI W4 tool steel). The magnetic field around a 2.94N-indentation was compared to that of a 294N-indentation. It was found that the decrease in the magnetic fields depends on the plastic deformation size.

Download Full-text

Vibration-Based Structural Damage Identification Under Interval Uncertainty

Volume 1: Advances in Control Design Methods, Nonlinear and Optimal Control, Robotics, and Wind Energy Systems; Aerospace Applications; Assistive and Rehabilitation Robotics; Assistive Robotics; Battery and Oil and Gas Systems; Bioengineering Applications; Biomedical and Neural Systems Modeling, Diagnostics and Healthcare; Control and Monitoring of Vibratory Systems; Diagnostics and Detection; Energy Harvesting; Estimation and Identification; Fuel Cells/Energy Storage; Intelligent Transportation ◽

10.1115/dscc2016-9874 ◽

2016 ◽

Author(s):

David Yoo ◽

Jiong Tang

Keyword(s):

Structural Damage ◽

Prior Information ◽

Random Distribution ◽

Damage Identification ◽

Interval Uncertainty ◽

Damage Location ◽

Physical Access ◽

Non Destructive ◽

Destructive Methods ◽

Fuzzy Interval

Identifying damages in mechanical structures in advance is essential part of preventing catastrophic losses. Among several non-destructive methods, the vibration-based method, which utilizes global characteristics of the structures, has several advantages such as not requiring prior information on possible damage location and physical access to it. In the meantime, the mechanical structures are inevitably subject to uncertainties, whose distribution is often unknown in practical situations due to such as limited amount of available data. Uncertainties are treated as interval uncertainty in such cases. In this regard, this study presents vibration-based damage identification under interval uncertainty. To obtain reliable result, this research does not assume any random distribution, e.g., uniform distribution, inside interval. Since detected damage is not assumed to be monotonic function with respect to interval uncertainty either, traditional fuzzy interval arithmetic is not applicable. Instead, we first carry out exhaustive search to see the effect of the interval uncertainty on the identified damage; i.e., discretizing interval uncertainty into sub-intervals and executing damage identification under all possible combinations to see the effect of the interval uncertainty on the identified damage. We then develop the unique algorithm based on M-H algorithm to facility computational efficiency.

Download Full-text

Estimation of Dislocation Density for AISI 304 Steel After Plastic Deformation Using Non-destructive Methods

Acta Physica Polonica B Proceedings Supplement ◽

10.5506/aphyspolbsupp.14.591 ◽

2021 ◽

Vol 14 (3) ◽

pp. 591

Author(s):

M. Sarnek ◽

E. Dryzek

Keyword(s):

Plastic Deformation ◽

Dislocation Density ◽

Aisi 304 ◽

Aisi 304 Steel ◽

Non Destructive ◽

Destructive Methods

Download Full-text

An Analysis of the Effectiveness of Application of Rotation Rate Sensors in Non Destructive Damage Evaluation

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.569-570.783 ◽

2013 ◽

Vol 569-570 ◽

pp. 783-790 ◽

Cited By ~ 1

Author(s):

Seweryn Kokot ◽

Zbigniew Zembaty ◽

Piotr Bobra

Keyword(s):

Rotation Rate ◽

Structural Damage ◽

Damage Identification ◽

Angular Rate ◽

Identification Problem ◽

Damage Evaluation ◽

Cantilever Beams ◽

Reconstruction Procedure ◽

Harmonic Vibrations ◽

Non Destructive

This paper reports the analysis of the effectiveness of the application of rotation rate sensors in structural damage identification problem using harmonic vibrations for plexiglass models of cantilever beams. The two types of sensors are applied: angular rate sensors and conventional translational, piezoelectric accelerometers. The amplitudes of dynamic response under harmonic kinematic excitations were subsequently used in the stiffness reconstruction procedure. Particularly promising results are obtained by using only rotation rate sensors in the reconstruction procedure.

Download Full-text