Microstructure, Hardness, and Wear Behavior of Layers Obtained by Electric Arc Hardfacing Processes.

Area of Science:

• Materials Science
• Welding Engineering
• Surface Engineering

Background:

• Hardfacing enhances component durability by depositing wear-resistant layers.
• Dilution between the hardfacing layer and substrate is a critical factor.
• Optimizing hardfacing parameters is key to improving abrasion resistance.

Purpose of the Study:

• To investigate the effect of shielded metal arc welding (SMAW) parameters on the wear resistance of hardfaced structural steel.
• To correlate microstructural features and mechanical properties with wear rate.
• To compare hardfaced steel with AISI D2 cold-work tool steel.

Main Methods:

• Hardfacing of structural steel using chromium carbide vanadium consumables via SMAW.
• Testing four different SMAW parameter sets (welding speed, current).
• Abrasive wear testing against silicon carbide (SiC) discs.
• Analysis of wear rate, microstructure (SEM), elemental composition (EDS), hardness, and surface roughness.

Main Results:

• Welding speed and current significantly impact wear resistance.
• Lower welding speeds and higher currents increased wear resistance.
• Increased heat input promoted the formation of larger, harder carbides, enhancing the deposited layer's durability.
• Wear rate correlated with microstructural characteristics and hardness.

Conclusions:

• Optimized SMAW parameters, specifically slower speeds and higher currents, enhance the abrasive wear resistance of hardfaced structural steel.
• The formation of larger, harder carbides is a key mechanism for improved wear performance.
• This study provides insights into controlling hardfacing properties for demanding applications.