Surface Modification of Mild Steel Using Tungsten Inert Gas Torch Surface Cladding

Abstract

<b>Problem statement:</b> There is an increasing demand for claddings which possess an optimized combination of different functional properties such as high hardness, high resistance to wear and oxidation. In this respect, hard TiAlN cladding has gained much attention. These claddings can be suitable replacements for the conventional ceramic coatings applied in many components of chemical plants and automotive industries to protect against high temperature oxidation and wear. <b>Approach:</b> In this study the possibility of the formation of intermetallic and nitride claddings on plain carbon steel surfaces by <i>in situ</i> melting of preplaced titanium and aluminum powder mixture under Tungsten Inert Gas (TIG) torch had been investigated. <b>Results:</b> Addition of 1.3 and 1.8 mg mm^-2 Ti and Al powder and melting at energy inputs between 540-675 J mm^-1 in nitrogen environment successfully created more than 1 mm thick clad layer consisting of a mixture of titanium-aluminum nitrides and aluminides. All resolidified melt layers produced dendrite microstructures; the dendrite concentration is more near the surface area compared to the deeper melt depth. A maximum surface hardness of around 900 Hv was developed in most of the tracks and this hardness corresponds to high concentration of dendrites within the modified layer. Oxidation at 600&deg;C for 72 h, of the clad steel gave weight gains of 0.13 mg mm^-2, compared to 0.37 mg mm^-2 for the substrate. <b>Conclusion:</b> The results showed that clad steel gave better mechanical and oxidation properties compared to plain carbon steel substrate

Surface alloying of AISI 1045 steel in a nitrogen environment using a gas tungsten arc process

“…The presence of porous edges and cracks was also observed in the nitrided layers. Dyuti et al (2010) …”

Evaluation of mechanical properties of TiB2-TiO2 ceramic composite coating on AISI 1020 mild steel by TIG cladding

“…The application of the mild steel in structural engineering, the components surface will be moving contact regularly therefore it is recommended that the surface properties be enhanced to the depth1 mm [22]. Greater than 1 mm hard layer can be deposited by using a high deposition rate cladding process such as laser cladding [23], TIG cladding [24,25], and plasma cladding. Laser cladding process provides very good refinement of the grains due to fast cooling and rapid solidification rate resulting in higher surface properties.…”

Creation of wear-resistant layers on steels using TIG electric arc surface remelting process with applying CaCN2-based nitriding powder

“…Signi cant reduction of energy and time requirements of layers enriched with a particular element (or elements) formation can be achieved by remelting the material surface layers with a tungsten inert gas (TIG) electric arc in an environment with an increased concentration of the element (or several elements), contained in a powder with a suitable chemical composition/microstructure. Dyuti et al remelted Ti powder [28] and Ti + Al powders [29] by TIG in shielding atmosphere N. A dendritic microstructure formed by titanium nitrides or nitrides and intermetallic phases based on Ti and Al was formed. A signi cant increase in the wear resistance of steels can also be achieved by remelting car-bide powders (WC, SiC, TiC) by TIG [30][31][32].…”