Laser Cladding of Fe-based Metallic Glass/MoS2 Self-lubricating Composites: Effect of Power and Scanning Speed

Author(s)

Giroto, Giovana ^[1] ; Gargarella, Piter ^[1] ; Riva, Rudimar ^[2] ; Kiminami, Claudio Shyinti ^[1] ; de Carvalho, Marcos Fernandes ^[1] ; Moreira Afonso, Conrado Ramos ^[1]

Affiliation

^[1] Univ Fed Sao Carlos, Dept Engn Mat DEMa, Rodovia Washington Luis, Km 245, BR-13565905 Sao Carlos, SP - Brazil

^[2] Inst Estudos Avancados IEAv, Trevo Coronel Aviador Jose Alberto Albano Amarant, BR-12228001 Sao Jose Dos Campos, SP - Brazil

• Document type: Journal article
• Source: MATERIALS RESEARCH-IBERO-AMERICAN JOURNAL OF MATERIALS; v. 20, n. 2, p. 836-841, 2017.
• Web of Science Citations: 1

Abstract

MoS2 powder has been used to form ``self-lubricating{''} composite coatings, which are very useful to increase the lifetime of machines where liquid lubricants cannot be used. In this work, amorphous overspray powder of Fe60Cr8Nb8B24 (at%) alloy was mixed with 5wt.% MoS2 powder and it was used to produce single tracks on AISI 1020 steel substrates by laser cladding. The tracks were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Vickers microhardness. It was observed alpha-Fe, an Nb-rich intermetallic and MoS2 particles in the tracks, regardless of laser parameter used. DSC analyses proved the presence of amorphous phase for samples produced with parameters 200W/33.3mm/s, 600W/100mm/s, 800W/100mm/s and 800W/150mm/s. The tracks produced with larger power (800W) and higher scanning speeds (100 and 150mm/s) exhibited a better integrity and homogeneity, lower dilution and presence of amorphous phase, being these parameters considered the most appropriate to produce composite coatings of Fe60Cr8Nb8B24 (at%)/5wt% MoS2 containing amorphous phase. Hardness tests showed that the single tracks produced are harder than the substrate, for example, the track produced with 800W/150mm/s exhibits hardness six times higher than the steel substrate, 1200 HV0.3 and 200 HV0.3, respectively. (AU)

• FAPESP's process: 13/05987-8 - Processing and characterization of amorphous, metastable and nano-structured metallic alloys
• Grantee: Claudio Shyinti Kiminami
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 14/13432-9 - Coatings of steel made of wear resistant nanocrystalline and amorphizable iron-based alloys
• Grantee: Marcos Fernandes de Carvalho
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 15/04062-6 - Coatings of fe-based metallic glasses and self-lubricating composites with MoS2 by laser cladding
• Grantee: Giovanna Giroto
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 12/18429-0 - Laser surface treatment of Amorphizable and nanocrystalline iron-based metallic alloys
• Grantee: Conrado Ramos Moreira Afonso
• Support Opportunities: Regular Research Grants