Friction surfaced tool steel (H13) coatings on low carbon steel: A study on the effects of process parameters on coating characteristics and integrity

• Published in: Surface & coatings technology Vol. 205; no. 1; pp. 232 - 242
• Main Authors: Rafi, H. Khalid, Ram, G.D. Janaki, Phanikumar, G., Rao, K. Prasad
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 25-09-2010; Elsevier
• Subjects: Applied sciences; Bond strength; Coating; Coatings; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Friction; Friction surfacing; Joining, thermal cutting: metallurgical aspects; Low carbon steels; Materials science; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Metals. Metallurgy; Microstructure; Physics; Process parameters; Production techniques; Rotational; Scanning electron microscopy; Shear testing; Solvents; Surface treatment; Surface treatments; Tool steel; Tool steels; Welding; Bond strength; Friction surfacing; Coating; Shear testing; Tool steel; Shear; Low carbon steel; Mechanical strength; Mechanical properties; Carbon steels; Surface treatments; Building up by welding; Coatings; Adhesion; Tool steels; Friction; Friction welding
• ISSN: 0257-8972; 1879-3347
• DOI: 10.1016/j.surfcoat.2010.06.052

Tool steel H13 was friction surfaced on low carbon steel substrates. Mechtrode (consumable rod) rotational speed and substrate traverse speed were varied, keeping the axial force constant. The effects of process parameters on coating characteristics and integrity were evaluated. A process parameter window was developed for satisfactory deposition of tool steel coatings. Coating microstructures were examined using optical microscopy, scanning electron microscopy, and transmission electron microscopy. Microhardness tests, shear tests, and bend tests were conducted on coatings. The results show that coating width is a strong function of mechtrode rotational speed, while coating thickness is mainly dependent on substrate traverse speed. Lower mechtrode rotational speeds results in wider coatings, while higher substrate traverse speeds produce thinner coatings. Thinner coatings exhibit higher bond strength than thicker coatings. Coatings show no carbide particles, yet exhibit excellent hardness (above 600 HV) in as-deposited condition due to their martensitic microstructure.