Mohd Basri Ali

Investigation of energy absorbed from an instrumented charpy impact on automotive specimens

This paper presents the analysis of energy absorbed that produced from an instrumented charpy impact in order to evaluate the toughness of materials. Alloy rims made from aluminium 6061-T6 are easily damage, fracture and can even destroy after impact loading compared to the steel rim. For this reason, an idea was initiated to determine the strain signal pattern and strain energy for evaluting the toughness of materials. Strain gauges were experimentally connected to the data acquisition system and it was then attached to the charpy striker for the impact signal collection. Specimens of aluminium alloy of 6061-T6 and carbon steel 1050 were used and its were designed according to the ASTM E23 standard. In this work, the signal was converted from the time domain to the frequency domain using the power spectrum density (PSD) method and the area under its graph was then used to calculate strain energy. The comparison between absorbed energy and strain energy was performed based on different materials and thicknesses. It was found the effect of the strain signal pattern with different materials and thicknesses to be influnced the strain energy.

Analysis of an instrumented charpy impact using power spectrum density

Dynamic fracture properties of most engineering materials are evaluated using Charpy test. The dynamic responses of the standard Charpy impact machine are experimentally studied using the relevant data acquisition system in order to obtain the impact response. For this reason, strain gauges were connected to the data acquisition set and it was then attached to the striker for the signal collection. The numerical analysis by mean of the finite element method has been used to obtain the findings. The standard Charpy modelling using the aluminium 6061 material was used in order to obtain strain responses on the striker during the impact simulation. A standard Charpy specimen aluminium 6061 was used for the experimental impact testing. A power spectrum density (PSD) approach is then used to convert a signal from the time domain to the frequency domain using the fast Fourier transform (FFT) method. Related parameters on strain signals, power spectrum density (PSD), comparison between experiment and finite element analysis, and the relationship between all the parameters were finally correlated and discussed. It was found that the finite element results are validated to show simulated time histories and its PSD compared with experimental work.

Test Simulation using Finite Element Method

The dynamic responses of the standard Charpy impact machine are experimentally studied using the relevant data acquisition system, for the purpose of obtaining the impact response. For this reason, the numerical analysis by means of the finite element method has been used for experiment findings. Modelling of the charpy test was performed in order to obtain strain in the striker during the test. Two types of standard charpy specimens fabricated from different materials, i.e. aluminium 6061 and low carbon steel 1050, were used for the impact simulation testing. The related parameters on between different materials, energy absorbed, strain signal, power spectrum density (PSD) and the relationship between those parameters was finally correlated and discussed.

Characterisation of the Sound and Vibration Signal of Impact Testing on Automotive Component Materials

Dynamic response of automotive component materials which are carbon steel S50C and cast ironon its sound and vibration characteristichas been studied. This paper shows that I-kaz analysis method can be applied to characterise this dynamic behavior problem. In the present work, an excitation has been performed by an impact hammer at the center of a rectangular bar specimen instrumented with accelerometer and microphone to obtain sound and vibration time-histories. From the experimental results, it was found that the recorded sound and vibration signal has a transient characteristic with high oscillation. Frequency spectrum analysis shows that impact testing on any material will generate its own characteristic of frequency peak and constantboth for sound and vibration signal. From I-kaz analysis method, it can be concluded that I-kaz coefficient, for sound signal is proportional to the modulus of elasticity, density and Poissons ratio. It is also shown that for vibration signal is inversely proportional to these mechanical properties.Data scattering representation supported this pattern of .

Experimental Analysis of an Instrumented Charpy Impact Using Signal Processing Approach

The dynamic responses of the standard charpy impact machine are experimentally studied using the relevant data acquisition system in order to obtain the impact response. For this reason, strain gauges were connected to the data acquisition set and it was then attached to the charpy striker for the signal collection. Aluminium 6061 and low carbon steel 1050 were used for extracting strain responses on the striker during the testing. In this work, the power spectrum density (PSD) approach was then used for the energy based observation and a signal was converted from the time domain to the frequency domain using the fast Fourier transform (FFT) method. Comparison between experimental findings with related parameters such as of different materials, strain signals pattern, I-kaz, were finally correlated and discussed. It was found that the modulus of elasticity were proportional to the energy absorbed, strain signals amplitude and PSD. Finally, it is suggested that the properties of materials and the impact signals pattern is suitable to be analysed using the signal processing approach.

Evaluating Charpy Impact Signals with Different Frequencies Using Power Spectrum Densities

The dynamic responses of the standard charpy impact machine are experimentally studied using the relevant data acquisition system in order to obtain the impact response. The numerical analysis by means of the finite element method has been used to obtain the findings. The standard charpy modelling using the aluminium 6061 material and low carbon steel 1050 were used for extracting strain responses on the striker during the impact simulation. A power spectrum density (PSD) approach is then applied to convert a signal from the time domain to the frequency domain using the fast Fourier transform (FFT) method. Related parameters of different frequencies, different material, strain signals, power spectrum density (PSD) and the relationship between them were finally correlated and discussed. It was found that the modulus elasticity of materials and frequencies (sample rates) were proportional to the strain signals and PSD during impact simulation.