Perm scientists' research will help select the best parameter set when repairing parts with the most complex shapes.
Thin-wall sample deformation
Use laser powder surfacing to repair worn or damaged metal parts. A powerful fiber laser creates a melt tank where the metal powder will then be automatically transported there. The problem that is often encountered in this process is that deformation of parts can be repaired under internal stress. This leads to a defect called warping.
When designing the process flow of laser powder surfacing to repair parts, predicting warping defects is one of the goals. Experimentally determining the best defect-free surfacing method for a particular part is unprofitable because both cost and time are high and often simply impossible.
Product Final Warp Modeling
To solve this problem, researchers from Perm Polytechnic Institute collaborated with JSC "ODK Aviativoil" to develop a mathematical model for laser powder surfacing warping calculation. Through numerical simulation, scientists can very accurately predict the behavior of parts during surfacing . Further development will help select the best parameter set when repairing parts with the most complex shapes.
Calculation surfacing model
This study was published in the "PNIPU Bulletin". "Aerospace Technology", 2022. The main idea for Perm Polytechnic scientists is to create a tool that can quickly and with high quality simulate the laser powder surfacing process, minimizing the final warping in repair work.
digitization results
"If the calculation is not performed, it is difficult to predict the behavior of products, especially small and thin-walled products at high temperatures. The defects that occur may ultimately lead to the unusable use of the parts being repaired. Therefore, in order to make a preliminary prediction of process parameters, we propose a method that uses numerical simulation.
This method will allow calculations before repair and evaluate warping. Our development will allow prediction of the behavior of parts during surfacing, which will reduce waste during repairs," said Marat Bekmansurov, a graduate student in the Department of Computational Mathematics, Mechanics and Biomechanics .
surfacing zone temperature gradient
Using experimental cylindrical samples, the developer calibrated the model based on the temperature field measurement results. The results help solve mechanical problems and determine the stress and strain fields in the surfacing materials and repair parts. Scientists simulate warping by dividing the surfacing section into orbits. Each track is divided into smaller elements to simulate a process as close to reality as possible.
verifies the correctness of the established model by comparing the simulation results with the actual laser powder surfacing results. The calculation results show that at the minimum time cost, the calculation accuracy is high enough to use the model in actual production.
