scholarly journals Increasing wear and corrosion resistance of steel products by combined laser thermomechanical treatment

2021 ◽  
Vol 6 (1 (114)) ◽  
pp. 72-80
Author(s):  
Oleksandr Danyleiko ◽  
Vitaliy Dzhemelinskyi ◽  
Dmytro Lesyk

A technique is presented for hardening metal products, in particular, the main tools (hammers) and cases of core drilling bits made of steel 30HGSA, using thermomechanical surface treatment according to a separate scheme. The method of combined laser thermomechanical hardening used in the study consists in the use of shot peening followed by laser heat treatment. Its use makes it possible to increase the operational properties of steel products, in particular, their wear and corrosion resistance. Based on the results of theoretical and experimental studies, the paper substantiates the features of dynamic surface plastic deformation for the analysis of impact during shot peening. The advantages of using laser hardening without surface melting are presented. Experimental research methods are proposed for determining the structural-phase composition, structure of the surface layer, hardness and microhardness of the hardened zones of steel 30HGSA. The range of rational modes of impact shot peening and thermal laser treatment has been determined. A device for testing samples for wear resistance has been developed. Methods of testing for wear and corrosion resistance of the surface of samples are proposed for assessing the tribological properties and contact interaction of materials under quasi-static and dynamic loading conditions. It is concluded that rational technological modes of hardening tools made of steel 30HGSA using combined laser thermomechanical treatment allow increasing the depth of the hardened layer by ~1.5 times compared to laser heat treatment. In addition, they provide the microhardness of the surface layer of ~5400 MPa, which is ~2.5 times higher than the microhardness of the base material

2012 ◽  
Vol 57 (1) ◽  
pp. 211-214 ◽  
Author(s):  
A. Bartkowska ◽  
A. Pertek ◽  
M. Jankowiak ◽  
K. Jóźwiak

Laser Surface Modification of Borochromizing C45 SteelIn this study the test results for borochromized C45 steel after laser surface modification were presented. Influence of laser heat treatment on the microstructure and microhardness of surface layer was investigated. The process of borochromizing consisted of chromium plating followed by diffusion boronizing. The laser heat treatment (LHT) of multiple tracks in the helical line was carried out with CO2laser beam. The technological laser TRUMPF TLF 2600 Turbo CO2of the nominal power 2.6 kW was applied. Borochromizing was carried out with laser power density q = 41.40 kW/cm2and at laser beam scanning rate v = 0.67 m/min and v = 2.016 m/min. Measurements of microhardness were conducted using the Vickers' method and Zwick 3212 B hardness tester. Microstructure observations were performed by means of an optical microscope Metaval Carl Zeiss Jena and scanning electron microscope Tescan VEGA 5135. After laser heat treatment with re-melting a three-zone layer was obtained, which included: re-melted zone, heat affected zone and a core. Influence of laser treatment parameters on thickness of melted zone and microstructure of the surface layer was tested. The microhardness tested along the axis of track of the surface layer after laser modification was about 800-850 HV. The results of tests showed influence of laser power density and scanning rate on microstructure and properties of borochromized layers.


2010 ◽  
Vol 638-642 ◽  
pp. 846-851 ◽  
Author(s):  
Abdoul Fatah Kanta ◽  
Véronique Vitry ◽  
Fabienne Delaunois

Nickel-boron coatings were synthesized on mild steel by the electroless deposition method. Some of the coatings were submitted to a hardening heat treatment at 400°C during 1 hour in an atmosphere containing 95% Ar and 5% H2. Uncoated steel, treated and untreated samples were submitted to the Taber abrasion test to assess their wear resistance. The wear track was then examined by SEM and roughness measurement. The Taber Wear Index of untreated samples was slightly better than that of steel but heat treated samples attained TWI as small as 13. The corrosion resistance of the samples was investigated by the way of polarization and electrochemical impedance spectroscopy (EIS) and the influence of the heat treatment was observed.


Author(s):  
C Dawes

Nitrotec is characterized as a low-distortion treatment for ferrous materials where surface enrichment, predominantly by nitrogen, forms a hard surface layer of epsilon iron nitride, beneath which there is a nitrogen diffusion zone. The surface layer imparts wear and corrosion resistance and the diffusion zone increases the yield and fatigue strength, particularly in thin section sizes. Process developments have significantly enhanced the corrosion resistance and aesthetic appearance of treated components to make Nitrotec competitive with electroplated finishes. Major commercialization took place during the 1980s with a wide range of successful applications from windscreen wiper systems to bumper armatures, using combinations of the unique properties obtainable from the process to provide cost and weight savings.


2008 ◽  
Vol 141-143 ◽  
pp. 755-760 ◽  
Author(s):  
Antonio Forn ◽  
Isabel Espinosa ◽  
Maite T. Baile ◽  
Elisa Rupérez

Semi solid processing reduces porosity and amount of trapped gas and it allows heat treatment T6 that improves a hard anodized oxide layer. The aim of this work is to show the anodizing possibility of A356 T6 components conformed by Sub-liquidus Casting (SLC) to improve wear and corrosion resistance. This work compares the anodizing effect on tribological properties and corrosion resistance between components obtained by A6061 T6 extruded alloys and from A356 T6 produced by SLC. The effect of rounded silicon crystals on the coating formation and the fracture produced during the coating growth are described.


2017 ◽  
Vol 309 ◽  
pp. 651-662 ◽  
Author(s):  
Marcela Rabelo Menezes ◽  
Cristina Godoy ◽  
V.T.L. Buono ◽  
Mônica M.M. Schvartzman ◽  
J.C. Avelar-Batista Wilson

2013 ◽  
Vol 419 ◽  
pp. 395-400 ◽  
Author(s):  
Cheng Hsien Yu ◽  
Jinn Jong Sheu

In this study, the preform and die designs of hot forging process were proposed for a long-flat slide block. This block is assembled to the linear slide for carrying the moving table. Three different billet geometry designs were proposed to obtain good die filling. The volume of the flash is limited to 30% with a flash thickness design in 3 mm. The forging die was designed with four ejectors to push up the forged part smoothly. The proposed billet geometries and die design were evaluated using CAE simulation. The simulation results indicated that the suitable perform design is able to achieve better material flow. The flash flow control is able to reduce the forming load and improve the die filling. The forging experiments were carried out to verify the proposed method, the experiment results showed good agreement with the CAE simulations. For the Improvement of wear and corrosion resistances of Inconel718 (In718) surface, high velocity oxygen fuel (HVOF) thermal spray coating of micron-sized WC-Cr-C-Ni powder was coated onto Inconel718 surface and laser heat-treatment of the coating was carried out. Porous coating of porosity 2.2±0.4% was prepared by HVOF coating, and it was improved by laser heat-treatment, reducing the porosity to 0.35±0.08%. Micro-hardness of laser heat-treated coating increased more than four times compared to the surface of In718. Friction coefficient decreased by HVOF coating and laser heat-treatment. Wear resistance improved, decreasing the wear depth by the coating and laser heating. The interface between coating and In718 was compacted, and elements diffused from both coating and inconel718 substrate to interface, forming metal rich buffer zone (interface) and enhancing the adhesion of coating. Corrosion resistance improved by coating in sea water 3.5% NaCl solution and in 1M HCl acid, but it worsened in 1M NaOH base. For the improvement of wear and corrosion resistances of Inconel718, HVOF WC-metal power coating and laser heat-treatment are recommended.


Author(s):  
Б.Д. Лыгденов ◽  
М.А. Гурьев ◽  
С.Г. Иванов ◽  
Ц. Чжэн ◽  
А.М. Гурьев

The paper presents ways to increase the wear and corrosion resistance of steel parts by chemical and thermal treatment methods. Comprehensive studies of the structure and properties of St3 steel samples were carried out after simultaneous complex saturation with boron and nickel, boron and tungsten from saturating coatings based on boron carbide. Both compounds of these elements (oxides, carbides, borides) and pure metals were used as suppliers of nickel and tungsten. Studies have shown that multicomponent saturation processes make it possible to form a multiphase structure of a surface layer with a complex of useful properties. Moreover, by chemical-thermal treatment it is possible to obtain such a combination of properties of the hardened product, which cannot be obtained by other methods.


Sign in / Sign up

Export Citation Format

Share Document