as the turbine industries need to manufacture turbine blades made of martensitic stainless steel aisi 420 with high toughness and wear resistance, local laser hardening has become more and more important. in this research, surface of the samples was initially hardened by high-power pulsed laser beam; then, optimum parameters of hardening were calculated and wear resistance of surface hardened s...

We report on the effect of femtosecond-laser-induced periodic surface structures (LIPSS) on the tribological properties of stainless steel. Uniform periodic nanostructures were produced on AISI 304L (American Iron and Steel Institute steel grade) steel surfaces using an 800-nm femtosecond laser. The spatial periods of LIPSS measured by field emission scanning electron microscopy ranged from 530...

An experimental model was proposed to study biofilm formation by Listeria monocytogenes ATCC 19117 on AISI 304 (#4) stainless steel surface and biotransfer potential during this process. In this model, biofilm formation was conducted on the surface of stainless steel coupons, set on a stainless steel base with 4 divisions, each one supporting 21 coupons. Trypic Soy Broth was used as bacterial g...

This study focuses on the semiconductor properties of passive films formed on AISI 420 stainless steel immersed in four nitric acid solutions under open circuit potential (OCP) conditions. For this purpose, the passivation parameters and semiconductor properties of passive films were derived from potentiodynamic polarization and Mott–Schottky analysis, respectively. The OCP plots showed that th...

An ultra-fine-grained AISI 301LN austenitic stainless steel has been achieved by heavy cold rolling, to induce the formation of martensite, and subsequent annealing at 800 C, 900 C, and 1000 C, from 1 to 100 seconds. The microstructural evolution was analyzed using transmission electron microscopy and the yield strength determined by tension testing. Ultra-fine austenite grains, as small as ~0....

Disinfectants play an important role in controlling microbial contamination on hard surfaces in hospitals. The effectiveness of disinfectants in real life can be predicted by laboratory tests that measure killing of microbes on carriers. The modified Quantitative Disk Carrier Test (QCT-2) is a standard laboratory method that employs American Iron and Steel Institute (AISI) Type 430 stainless st...

We have taken advantage of the native surface roughness and the iron content of AISI 316 stainless steel to directly grow multi-walled carbon nanotube (MWCNT) random networks by chemical vapor deposition (CVD) at low-temperature (1000°C) without the addition of any external catalysts or time-consuming pre-treatments. In this way, super-hydrophobic MWCNT films on stainless steel sheets were obta...

Laser beam welding (LBW) is one of the most important manufacturing processes used for joining of materials. It is also a remarkably complicated, nonlinear operation involving extremely high temperatures. Since its invention more than two decades ago, laser beam welding has been more of an art than a science. Laser welding of austenitic stainless steel AISI 304 the candidate material of this re...

Thanks to the collaboration between two laboratories, we present different techniques to measure thermal diffusivity. A brief description of any technique both in the experimental layout and in the processing algorithms is given. Results obtained on samples cut from the same block of stainless steel AISI 304, are reported. Uncertainty evaluation of any measurement is reported as well.

The purpose of the tests was to determine whether and how sterilisation process of samples made of AISI 316L stainless steel with diff erent strain impacts their corrosion resistance. Tests were made on steel samples that had been electrochemically polished in order to assure proper surface roughness. In order to evaluate the infl uence of sterilisation on physical and chemical properties of st...