Analysis on Mechanical Properties of Instrumented Indentation Tester Frame

2012 ◽  
Vol 215-216 ◽  
pp. 895-898
Author(s):  
Jun Hong Guo ◽  
De Jun Ma ◽  
Wei Chen ◽  
Zhong Kang Song
Keyword(s):  
High Precision ◽  
Inclination Angle ◽  
Indentation Load ◽  
Measurement Precision ◽  
Instrumented Indentation ◽  
Element Analysis ◽  
Maximum Value ◽  
Load Analysis ◽  
The Relationship ◽  
Maximum Inclination

Finite element analysis is undertaken to identify the extent of loading deformation of instrumented indentation equipment frame which is a main part in High-precision instrumented indentation tester developed and realized by our group. The working load enacted in the model is varied from 10N to 100N, and the increment load is 10N. By plotting and fitting data of inclination angle and working load, the relationship between frame inclination angle and working load is established. The function of this relationship is θ=0.000024*F. When the working load is up to the upper bound 100N, the inclination angle of frame reaches the maximum value 0.00241°.Load analysis of push rod shows that the percent error between measured load values and real indentation load values caused by maximum inclination angle is in 10-8order. The conclusion is thus derived that frame inclination has nearly no effects on load measurement precision. The research in this paper confirms that the design of frame belonging to High-precision instrumented indentation tester is appropriate.

Analysis of Pop-In Phenomenon in the Process of Ceramic Materials Instrumented Indentation

2014 ◽  
Vol 941-944 ◽  
pp. 564-568
Author(s):  
Jia Liang Wang ◽  
De Jun Ma ◽  
Wei Chen ◽  
Yong Huang ◽  
Liang Sun
Keyword(s):  
Radial Crack ◽  
Ceramic Materials ◽  
Mechanism Analysis ◽  
Analysis Method ◽  
Instrumented Indentation ◽  
Element Analysis ◽  
Lateral Crack ◽  
Indentation Process ◽  
The Finite Element Analysis ◽  
The Relationship

Based on the finite element analysis method, the relationship between two systems of crack (radial crack and lateral crack) and pop-in phenomenon were compared during the instrumented indentation process in ceramic materials. In order to give a reasonable explanation for mechanism analysis of pop-in phenomenon in the process of ceramic materials instrumented indentation, this paper proposed the viewpoint that pop-in phenomenon is caused by the lateral crack in the process of ceramic materials instrumented indentation. This work provided a theoretical basis for the study of instrumented indentation methodologies based on the pop-in phenomenon to determining mechanical properties of ceramic materials.

Determination of Residual Stress Directionality by Instrumented Indentation Testing Using Anisotropic Indenter

2018 ◽  
Author(s):  
Sungki Choi ◽  
Jong Hyoung Kim ◽  
Jun Sang Lee ◽  
Kyungyul Lee ◽  
Min-Jae Choi ◽  
...  
Keyword(s):  
Residual Stress ◽  
Indentation Test ◽  
Surface Preparation ◽  
Field Testing ◽  
Indentation Load ◽  
Indentation Testing ◽  
Instrumented Indentation ◽  
Element Analysis ◽  
Knoop Indenter ◽  
Depth Curves

Residual stress is a major factor in failure and fracture in structures or electronic components. Various testing methods are used to measure residual stress: there are saw-cutting, holedrilling, X-ray diffraction and layer-removing methods. In particular, instrumented indentation testing (IIT) has many advantages: it is a simple and non-destructive procedure that can be used for in-field testing. In previous research, we proposed an algorithm for evaluating the magnitude and directionality of residual stress using an asymmetric Knoop indenter with long and short axes in the ratio 7.11:1. Indenting in different directions with a Knoop indenter creates different indentation load-depth curves depending on the residual stress state. In addition, the directionality of the residual stress can be expressed as a function of the load difference ratio calculated from these load-depth curves. However, When the Knoop indentation test is performed at small indentation depths, experimental issues such as surface preparation or indentation normality can become significant as the load difference decreases. In order to solve these issues, we introduce a wedge indenter, that makes it possible to select the edge length independent of indentation depth. We can thus decrease indent size when working in a small testing area. The load difference between the stress-free and stressed state is related to the sensitivity of residual stresses, and a wedge indenter can maximize the sensitivity to residual stress. In this study, we suggest a way to use the wedge indenter and verify the model using cruciform bending specimens and finite element analysis.

Effect of Water Immersion on Interfacial Strength of a Metal/Epoxy Joint

2018 ◽  
Vol 774 ◽  
pp. 289-294
Author(s):  
Yasuhiro Yamazaki ◽  
Katsu Kudo
Keyword(s):  
Water Immersion ◽  
Indentation Test ◽  
Interfacial Strength ◽  
Indentation Load ◽  
Interfacial Fracture Toughness ◽  
Instrumented Indentation ◽  
Service Water ◽  
In Situ Observations ◽  
The Relationship

Metal/resin joints have been widely used for automotive, electrical device and others. The degradation of interfacial strength of the joints through the effects of moisture is one of the important deterioration mechanisms in their structure applications. In this study, the interfacial strength of an aluminum-alloy/epoxy-resin joint was evaluated by the indentation test using of the instrumented indentation machine developed by ourselves. The in-situ observations of delamination cracking were carried out during the indentation test. The interfacial fracture toughness of the joint was evaluated from the relationship between the indentation load and the crack length. The effect of immersion into service water on the evaluated interfacial strength of the joint was discussed.

scholarly journals Investigation on a No Trial Weight Spray Online Dynamic Balancer

2018 ◽  
Vol 2018 ◽  
pp. 1-15 ◽  
Author(s):  
Xialun Yun ◽  
Xuesong Mei ◽  
Gedong Jiang ◽  
Zhenbang Hu ◽  
Zunhao Zhang
Keyword(s):  
High Precision ◽  
High Speed ◽  
High Efficiency ◽  
Vibration Suppression ◽  
Influence Coefficient ◽  
Analysis Model ◽  
Dynamic Balancing ◽  
Element Analysis ◽  
Balance Test ◽  
The Relationship

In order to suppress the spindle vibration with high efficiency and high precision, a no without trial weight spray online balance method is proposed in this paper. By analyzing the relationship between the unbalanced excitation and the unbalanced response of the spindle, the relationship between the dynamic influence coefficient and the system model is studied. A high-speed spindle finite element analysis model was established, and the dynamic influence coefficient matrix was identified. A no trial weight spray online dynamic balancing system was developed, which has the advantages of without trial weight and high-precision loading. A new type of integrated balancing terminal that was formed using 3D printing technology was first proposed by our research group, and its advantages in various aspects are significantly higher than traditional assembly balanced terminals. The experimental verification of the without trial weight spray online dynamic balancing system was performed on a high-speed spindle test stand. Experiments show that the no trial weight spray online balancing method proposed in this paper can achieve high-efficiency and high-precision vibration suppression, greatly reducing balance time and cost of the spindle. At the same time, the online balance test also verified the reliability of the integrated balanced terminal.

Determining Brinell Hardness From Analysis of Indentation Load-Depth Curve Without Optical Measurement

2005 ◽  
Vol 127 (1) ◽  
pp. 154-158 ◽  
Author(s):  
Sung-Hoon Kim ◽  
Eun-chae Jeon ◽  
Dongil Kwon
Keyword(s):  
Optical Measurement ◽  
Brinell Hardness ◽  
Indentation Load ◽  
Residual Lifetime ◽  
Element Analysis ◽  
Hardness Tests ◽  
The Relationship ◽  
Hardness Values ◽  
Depth Curve ◽  
Work Hardening Exponent

Hardness tests are performed to determine not only hardness but also other properties such as strength, wear resistance, and deformation resistance. They are also performed to predict residual lifetime through analysis of the hardness reduction or hardness ratio. However, hardness tests require observation of the residual indentation, and for that reason are not widely used in industrial fields. This study thus examines obtaining Brinell hardness values without optical observation, using instead quantitative formulas and analyzing the relationship between the indentation depths from the indentation load-depth curve and mechanical properties such as the work-hardening exponent, yield strength, and elastic modulus on the basis of finite-element analysis.

Analysis of magnetic force and dynamic characteristic for non-contact permanent magnet linear drive device

2020 ◽  
Vol 64 (1-4) ◽  
pp. 1337-1345
Author(s):  
Chuan Zhao ◽  
Feng Sun ◽  
Junjie Jin ◽  
Mingwei Bo ◽  
Fangchao Xu ◽  
...  
Keyword(s):  
Finite Element ◽  
Permanent Magnet ◽  
Dynamic Characteristic ◽  
Driving Force ◽  
Magnetic Circuit ◽  
Response Speed ◽  
Computation Method ◽  
Element Analysis ◽  
Element Simulation ◽  
The Relationship

This paper proposes a computation method using the equivalent magnetic circuit to analyze the driving force for the non-contact permanent magnet linear drive system. In this device, the magnetic driving force is related to the rotation angle of driving wheels. The relationship is verified by finite element analysis and measuring experiments. The result of finite element simulation is in good agreement with the model established by the equivalent magnetic circuit. Then experiments of displacement control are carried out to test the dynamic characteristic of this system. The controller of the system adopts the combination control of displacement and angle. The results indicate that the system has good performance in steady-state error and response speed, while the maximum overshoot needs to be reduced.

Regularities and properties of instrumented indentation diagrams obtained by ball-shaped indenter

2020 ◽  
Vol 86 (5) ◽  
pp. 43-51
Author(s):  
V. M. Matyunin ◽  
A. Yu. Marchenkov ◽  
N. Abusaif ◽  
P. V. Volkov ◽  
D. A. Zhgut
Keyword(s):  
Yield Strength ◽  
Ultimate Strength ◽  
Elastoplastic Deformation ◽  
Elastic Limit ◽  
Tensile Tests ◽  
Indentation Load ◽  
International Standards ◽  
Instrumented Indentation ◽  
Indentation Methods ◽  
Special Points

The history of appearance and the current state of instrumented indentation are briefly described. It is noted that the materials instrumented indentation methods using a pyramid and ball indenters are actively developing and are currently regulated by several Russian and international standards. These standards provide formulas for calculating the Young’s modulus and hardness at maximum indentation load. Instrumented indentation diagrams «load F – displacement α» of a ball indenter for metallic materials were investigated. The special points on the instrumented indentation diagrams «F – α» loading curves in the area of elastic into elastoplastic deformation transition, and in the area of stable elastoplastic deformation are revealed. A loading curve area with the load above which the dF/dα begins to decrease is analyzed. A technique is proposed for converting «F – α» diagrams to «unrestored Brinell hardness HBt – relative unrestored indent depth t/R» diagrams. The elastic and elastoplastic areas of «HBt – t/R» diagrams are described by equations obtained analytically and experimentally. The materials strain hardening parameters during ball indentation in the area of elastoplastic and plastic deformation are proposed. The similarity of «HBt – t/R» indentation diagram with the «stress σ – strain δ» tensile diagrams containing common zones and points is shown. Methods have been developed for determining hardness at the elastic limit, hardness at the yield strength, and hardness at the ultimate strength by instrumented indentation with the equations for their calculation. Experiments on structural materials with different mechanical properties were carried out by instrumented indentation. The values of hardness at the elastic limit, hardness at the yield strength and hardness at the ultimate strength are determined. It is concluded that the correlations between the elastic limit and hardness at the elastic limit, yield strength and hardness at the yield strength, ultimate tensile strength and hardness at the ultimate strength is more justified, since the listed mechanical characteristics are determined by the common special points of indentation diagrams and tensile tests diagrams.

Redrawing Operation a Star Shape from Cylindrical Shape Using Experimental and FE Analysis

2020 ◽  
Vol 38 (1A) ◽  
pp. 25-32
Author(s):  
Waleed Kh. Jawad ◽  
Ali T. Ikal
Keyword(s):  
Finite Element ◽  
Effective Strain ◽  
Element Model ◽  
Cylindrical Shape ◽  
Element Analysis ◽  
Punch Force ◽  
Maximum Value ◽  
Element Simulation ◽  
Blank Sheet ◽  
The Finite Element Model

The aim of this paper is to design and fabricate a star die and a cylindrical die to produce a star shape by redrawing the cylindrical shape and comparing it to the conventional method of producing a star cup drawn from the circular blank sheet using experimental (EXP) and finite element simulation (FES). The redrawing and drawing process was done to produce a star cup with the dimension of (41.5 × 34.69mm), and (30 mm). The finite element model is performed via mechanical APDL ANSYS18.0 to modulate the redrawing and drawing operation. The results of finite element analysis were compared with the experimental results and it is found that the maximum punch force (39.12KN) recorded with the production of a star shape drawn from the circular blank sheet when comparing the punch force (32.33 KN) recorded when redrawing the cylindrical shape into a star shape. This is due to the exposure of the cup produced drawn from the blank to the highest tensile stress. The highest value of the effective stress (709MPa) and effective strain (0.751) recorded with the star shape drawn from a circular blank sheet. The maximum value of lamination (8.707%) is recorded at the cup curling (the concave area) with the first method compared to the maximum value of lamination (5.822%) recorded at the cup curling (the concave area) with the second method because of this exposure to the highest concentration of stresses. The best distribution of thickness, strains, and stresses when producing a star shape by

scholarly journals Design, Analysis and Test of a Hyperbolic Magnetic Field Voice Coil Actuator for Magnetic Levitation Fine Positioning Stage

Energies ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1830
Author(s):  
Yiheng Zhou ◽  
Baoquan Kou ◽  
He Zhang ◽  
Lu Zhang ◽  
Likun Wang
Keyword(s):  
Magnetic Field ◽  
High Precision ◽  
Magnetic Levitation ◽  
Structural Parameters ◽  
Industrial Applications ◽  
Degree Of Freedom ◽  
Force Density ◽  
Precision Positioning ◽  
Element Analysis ◽  
Voice Coil Actuator

The multi-degree-of-freedom high-precision positioning system (MHPS) is one of the key technologies in many advanced industrial applications. In this paper, a novel hyperbolic magnetic field voice coil actuator using a rhombus magnet array (HMF-VCA) for MHPS is proposed. Benefiting from the especially designed rhombus magnet array, the proposed HMF-VCA has the advantage of excellent force uniformity, which makes it suitable for multi-degree-of-freedom high-precision positioning applications. First, the basic structure and operation principles of the HMF-VCA are presented. Second, the six-degree-of-freedom force and torque characteristic of the HMF-VCA is studied by three-dimensional finite element analysis (3-D FEA). Third, the influence of structural parameters on force density and force uniformity is investigated, which is conducive to the design and optimization of the HMF-VCA. Finally, a prototype is constructed, and the comparison between the HMF-VCA and conventional VCAs proves the advantage of the proposed topology.

Metric for Disassembly and Reuse Decisions: Formulation and Validation

2008 ◽  
Author(s):  
Vijitashwa Pandey ◽  
Deborah Thurston
Keyword(s):  
Maximum Likelihood ◽  
Value Function ◽  
Choice Theory ◽  
Decision Makers ◽  
Maximum Likelihood Estimates ◽  
Likelihood Method ◽  
Maximum Value ◽  
Long Range Planning ◽  
The Relationship ◽  
The Value Function

Design for disassembly and reuse focuses on developing methods to minimize difficulty in disassembly for maintenance or reuse. These methods can gain substantially if the relationship between component attributes (material mix, ease of disassembly etc.) and their likelihood of reuse or disposal is understood. For products already in the marketplace, a feedback approach that evaluates willingness of manufacturers or customers (decision makers) to reuse a component can reveal how attributes of a component affect reuse decisions. This paper introduces some metrics and combines them with ones proposed in literature into a measure that captures the overall value of a decision made by the decision makers. The premise is that the decision makers would choose a decision that has the maximum value. Four decisions are considered regarding a component’s fate after recovery ranging from direct reuse to disposal. A method on the lines of discrete choice theory is utilized that uses maximum likelihood estimates to determine the parameters that define the value function. The maximum likelihood method can take inputs from actual decisions made by the decision makers to assess the value function. This function can be used to determine the likelihood that the component takes a certain path (one of the four decisions), taking as input its attributes, which can facilitate long range planning and also help determine ways reuse decisions can be influenced.

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