The effect of working distances on the formation of TiC composite surface hardening using TIG melting technique

• Main Authors: Md Idriss, A. N., Maleque, Md. Abdul, Afiq, A
• Format: Conference or Workshop Item
• Language: English; English; English; English; English
• Published: 2021
• Subjects: T11.95 Industrial directories; TN600 Metallurgy; TN799.5 Nonmetallic minerals; TP200 Manufacture and use of chemicals; TS200 Metal manufactures. Metalworking
• Online Access: http://irep.iium.edu.my/90440/1/1%20Brochure%20ICMAAE%2021.pdf; http://irep.iium.edu.my/90440/3/4%20Registration%20fee_34.pdf; http://irep.iium.edu.my/90440/4/5%20IEC2021ProgrammeBook.pdf; http://irep.iium.edu.my/90440/5/Slides%20for%20ICMAAE21.pdf; http://irep.iium.edu.my/90440/31/90440_The%20effect%20of%20working%20distances%20on%20the%20formation.pdf; http://irep.iium.edu.my/90440/
• Institution: Universiti Islam Antarabangsa Malaysia

Hardening surface layer with and without adding reinforcing material can be achieved by rapid solidification on the top substrate area via high energy input fusion. In this work, the TIG torch heat input at 1344 J/mm is fused at 0.5 mm and 1.5 mm of working distances to incorporate the preplaced TiC particulates on the surface of AISI 4340 low alloy steel. Results pertaining to the microstructural features, melt pool sizes, defects, topographies and microhardness were investigated using the optical microscope, scanning electron microscope and Vickers microhardness tester. The results showed that the heat loss through the arc column at 1.5 mm of working distance resulted small melt pool geometry and poor dissolution of TiC particulates. Narrowing this gap to 0.5 mm increases heating that made more precipitation of TiC whilst minimizing those the undissolved particulates. The surface engulfed with TiC of 0.5 mm near the arc source produced microhardness ranging from 800 HV to 1500 HV. The work suggested that heat fusion can be enhanced by marginal working distance whilst saving the energy to melt instead of increasing the used voltage, current, decreasing scanning speed or by preheating, post heating or adding fluxes shielding with special shielding gasses.