Experimental Comparison of Laser Cladding and Powder Plasma Transferred Arc Welding Methods for Depositing Wear-Resistant NiSiB + 60% WC Composite on a Structural-Steel Substrate

Abstract

A Ni-based powder composed of NiSiB + 60% WC was deposited onto a structural-steel substrate using two methods: laser cladding (LC) and plasma powder transferred arc welding (PPTAW). The resulting surface layers were analyzed and compared. Both methods resulted in the precipitation of secondary WC phases in the solidified matrix, but the PPTAW clad exhibited a dendritic microstructure. The microhardness of the clads prepared by both methods was similar, but the PPTAW clad showed higher resistance to abrasive wear compared to the LC clad. The thickness of the transition zone (TZ) was thin for both methods, with a coarse-grain heat-affected zone (CGHAZ) and peninsula-like macrosegregations observed in clads from both methods. The PPTAW clad showed a unique cellular–dendritic growth solidification (CDGS) and a type-II boundary at the TZ attributed to its thermal cycles. While both methods resulted in metallurgical bonding of the clad to the substrate, the LC method exhibited a lower dilution coefficient. The LC method also resulted in a larger HAZ with higher hardness compared to the HAZ of the PPTAW clad. The findings of this study indicate that both methods are promising for antiwear applications due to their wear-resistant properties and metallurgical bonding to the substrate. The PPTAW clad may be particularly useful in applications that require higher resistance to abrasive wear, while the LC method may be advantageous in applications that require lower dilution and larger HAZ.

Improving the Properties of Gray Cast Iron by Laser Surface Modification

“…Many traditional surface treatment techniques have been used to improve the mechanical, physical, and chemical properties of the surfaces of metal parts, such as surface coating, diamond-like carbon (DLC) [ 4 , 5 ], abrasive jet machining (AJM) [ 6 , 7 ], micro-electrical etching (MEE) [ 8 ], etc. However, based on the fast-growing laser technology, laser surface treatment is becoming more popular in functional surface modification due to its advantages that have been widely studied in recent decades [ 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 ]. Laser quenching has been shown to be an effective approach to improve the wear resistance, residual stress, local hardness, and structural mechanical properties of functional materials.…”