Microstructure and Cavitation Erosion Resistance of the X2CrNiMoN22-5-3 Duplex Stainless Steel Subjected to Laser Nitriding

The cavitation behavior of the Duplex stainless steel X2CrNiMoN22-5-3 was improved by modifying the structure of the surface layer, using the laser nitriding procedure. There have been used different impulse power for the laser beam (from 120W to 240W) for constant impact times. The cavitation erosion tests were effectuated in the Timisoara Poytechnic University Cavitation Erosion Laboratory with the T2 device, which respects all the conditions imposed by the ASTM G32 Standard. There were compared two types of specimens: those laser treated and those subjected only to the conventional solution treatment (heated at 1060 oC and cooled in water). The eroded surfaces were analyzed through hardness measurements, optic microscopy and scanning electronic microscopy (SEM). After a total cavitation exposure of 165 min, the specimens laser nitridet present a reduction of 3.23 till 5.67 times of the mean depth erosion and from 3.03 till 5.26 times of the cavitation erosion rate in comparison with the specimens treated only with solution treatment. This huge improvement is given by the microstructure of the superficial layer enriched in nitrogen.

[1]  L. Micu,et al.  A New Model for the Equation Describing the Cavitation Mean Depth Erosion Rate Curve , 2017 .

[2]  C. Crăciunescu,et al.  Cavitation Erosion Mechanisms of Solution Treated X5CrNi18-10 Stainless Steels , 2016 .

[3]  C. Crăciunescu,et al.  Cavitation Erosion of Sensitized UNS S31803 Duplex Stainless Steels , 2016, Journal of Materials Engineering and Performance.

[4]  L. Pîrvulescu,et al.  Cavitation Erosion of HVOF Metal-ceramic Composite Coatings Deposited onto Duplex Stainless Steel Substrate , 2016 .

[5]  C. Crăciunescu,et al.  Ultrasonic cavitation erosion of nodular cast iron with ferrite-pearlite microstructure. , 2015, Ultrasonics sonochemistry.

[6]  Alejandro Toro,et al.  Cavitation resistance, microstructure and surface topography of materials used for hydraulic components , 2010 .

[7]  Ryohei Ishikura,et al.  Revision of cavitation erosion database and analysis of stainless steel data , 2010 .

[8]  B. Ghiban,et al.  Chemical and Mechanical Aspects of the Cavitation Phenomena , 2007 .

[9]  V. Wesling,et al.  Cavitation erosion resistance of AISI 420 martensitic stainless steel laser-clad with nickel aluminide intermetallic composites and matrix composites with TiC reinforcement , 2006 .

[10]  Tracy W. Nelson,et al.  Microstructure and mechanical properties of friction stir welded SAF 2507 super duplex stainless steel , 2005 .

[11]  G. Bregliozzi,et al.  Cavitation wear behaviour of austenitic stainless steels with different grain sizes , 2005 .

[12]  A. Al-Hashem,et al.  The effect of duplex stainless steel microstructure on its cavitation morphology in seawater , 2001 .

[13]  F. Cheng,et al.  Cavitation erosion and damage mechanisms of alloys with duplex structures , 1998 .

[14]  D. West,et al.  Laser Surface Nitriding of Titanium and a Titanium Alloy , 1992 .

[15]  Joseph R. Davis,et al.  Friction, lubrication, and wear technology , 1992 .

[16]  A. Karimi.  Cavitation erosion of a duplex stainless steel , 1987 .

[17]  Frederick G. Hammitt,et al.  Standard method of vibratory cavitation erosion test - (modified): (4th preliminary draft) : includes tests for various temperature, pressure and liquid conditions , 1975 .