An integrated approach for the modelling of silicon carbide components laser milling process

Claudio Leone,Silvio Genna,Vincenzo Tagliaferri

doi:10.1007/s00170-021-07516-2

Abstract

The paper deals with characterisation and modelling of laser milling process on silicon carbide hard ceramic. To this end, a Yb:YAG pulsed fiber laser was adopted to mill silicon carbide bars. Square pockets, 5×5 mm2 in plane dimension, were machined at the maximum nominal average power (30W), under different laser process parameters: pulse frequency, scan speed, hatching distance, repetitions and scanning strategy. After machining, the achieved depth and the roughness parameters were measured by way of digital microscopy and 3D surface profiling, respectively. In addition, the material removal rate was calculated as the ratio between the removed volume/process time. Analysis of variance (ANOVA) was adopted to assess the effect of the process parameters on the achieved depth, the material removal rate (MRR) and roughness parameters, while response surface methodology (RSM) and artificial neuronal networks (ANNs) were adopted to model the process behaviours. Results show that both RSM and ANNs fault in MRR and RSm roughness parameters modelling. Thus, an integrated approach was developed to overcome the issue; the approach is based on the use of the RSM model to obtain a hybrid Training dataset for the ANNs. The results show that the approach can allow improvement in model accuracy.Graphical abstract

Highlights

Silicon carbide (SiC) is a high-performance advanced or technical ceramic; it has attracted increasing attention thanks to its superior properties in terms of specific strength, specific modulus, hardness, wear resistance, thermal and chemical resistance and thermal stability
The results show that the approach can allow improvement in model accuracy, since the Errors [%] are reduced to 14.9 and 14.3 for RSm and material removal rate (MRR), respectively
Laser milling of SiC advanced ceramic was performed by way of a 30-W Q-switched Yb:YAG fiber laser changing the scan speed, the pulse frequency, the hatching distance, the repetition and the strategy

Summary

Introduction

Silicon carbide (SiC) is a high-performance advanced or technical ceramic; it has attracted increasing attention thanks to its superior properties in terms of specific strength, specific modulus, hardness, wear resistance, thermal and chemical resistance and thermal stability. Laser milling (LM) is a competitive process to machine advanced ceramics [2, 10,11,12,13,14,15]. In this technique, the laser beam removes material layer by layer following predetermined patterns. The machined surface can be varied to obtain 2D 1⁄2 shapes

Results

Discussion

Conclusion