Scientific paper ID 2239 : 2022/3
VIBRO-ACOUSTIC EVALUATION OF THE JUNG MODULE OF 3D PRINTED SAMPLES. APPROVAL OF RESEARCH METHODOLOGY
Approbation of the methodology for vibro-acoustic determination of the modulus of linear deformation of polymer samples produced by 3D printing is the task of this work. The specimens are made to study the impact toughness of the material and have a square cross-section, with a slit in the middle.
A method for determining the modulus of elastic deformation by vibro-acoustic method has been adapted. On the base on Newton”s second law, it is established that there is an analytical relationship between material density, Jung modulus and bending resonances of beams with constant cross section. However it is not applicable to specimens of another shape. Therefore, empirical dependencies between the above parameters have been created using the finite element method. They are created by calculation the resonant frequencies of 3D models of printed samples for different values of density and Jung modules.
The methodology was tested by studying 8 standard samples. The following parameters have been changed: speed, degree of filling, step of vertical displacement of the nozzle and temperature of the material when printing in the range recommended by the material manufacturer. The resonant frequencies of the tested samples in the range up to 20 kHz were measured and their masses were measured with an accuracy of 5 mg. Taking into account the volume of the model, the density of the material for the samples was calculated. According to the created empirical dependence, the values for the modulus of linear deformation for each sample are obtained.
A change in the density of the material was found from 1132 to 1428 kg / m3, and the modulus of linear deformation - from 800 to 1965 MPa. Destructive research is to be conducted in comparison with the obtained data.
The conducted researches give grounds to believe that the used methodology is also applicable for control of machine elements produced by energy saving technologies.
модул на линейна деформация на полимерни материали принтирани при различни технологични режимиJung module of polymeric materials printed in different technological modesIvan Kolarov
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