Please see one of my recent papers to be published in the near future. It has taken some effort to see this work through but we finally got there in the end, and it brings a great pleasure to get it published in a journal like the European Ceramic Society. The paper is entitled "Surface Property Modification of Silicon Carbide ceramics following Laser Shock Peening". To my knowledge this is the first paper on LSP SiC ceramics and has shown some decent results which we tried to investigate broadly, it does need further work to rationalize some of the findings. It discusses the effects of LSP on hardness, fracture toughness, fracture morphology, residual stress and phase transformation with respect to changes in energy density. Please see abstract and the online link to the paper below:
“This paper is focused on Laser shock processing (LSP) of silicon carbide (SiC) advanced ceramic. A comprehensive study was undertaken using a pulsed Nd:YAG laser. Surface modifications were investigated, particularly: the roughness, hardness, fracture toughness, microstructure, phase transformation and residual stress induced before and after the LSP surface treatment. The findings showed increase in the surface roughness, changes to the surface morphology, improved hardness, and a reduction in the fracture lengths. The LSP surface treatment also improved the surface fracture toughness from an average of 2.32 MPa.m1/2 to an average of 3.29 MPa.m1/2. This was attributed to the surface integrity and the induced compressive residual stress as a maximum of -92 MPa was measured compared to an average of +101 MPa on the as-received SiC. A slight change in the surface chemistry was also observed from the XPS spectra, however, no real phase transformation was observed from the X-Ray diffraction analysis. Laser energy density of around 1.057 J/cm2, 8.5 mm spot size, 10Hz pulse repetition rate (PRR) at 6ns pulse duration, and 1064nm wavelength resulted to obtaining a crack-free surface treatment and demonstrated that the technique is also beneficial to enhance some of the properties to strengthen brittle ceramics such as SiC”.
Click on link to acess the paper:
Pratik Shukla, Subhasisa Nath, Guanjun Wang, Xiaojun Shen, Jonathan Lawrence (2017), Surface property modifications of silicon carbide ceramic following laser shock peening, Journal of European Ceramic Society. In Press.