Homogeneity, metallurgical, mechanical, wear, and corrosion behavior of Ni and B4C coatings deposited on 304 stainless steels developed by microwave cladding technique

Abstract

The microwave cladding technique for depositing Ni and 10 % B4C coatings on 304 stainless steel has yielded significant advancements in material properties and performance. The key findings of this study revealed remarkable improvements, including a 43.33% increase in material hardness, indicating enhanced wear resistance and mechanical properties. This improvement was attributed to the uniform distribution of B4C and Ni on the cladding surface, ensuring a consistent interfacial layer developed between SS 304 and the cladding surface without cracks and porosity. Microstructural analysis at 500× magnification unveiled an impressive 2233.35 grains per square inch, showcasing the refined grain structure achieved during the cladding process. Wear testing demonstrated a low wear rate of 0.00308 mm³/m and a favorable coefficient of friction of 0.1981, confirming the material's suitability for applications with demanding frictional conditions. Furthermore, the corrosion behavior of the coated 304 stainless steel was assessed, revealing a minimal corrosion weight loss of only 0.42 mg for the Ni and 10% B4C coated sample. The presence of various carbide phases, such as Cr2C, Cr23C6, Cr7BC4, Fe5C2, and Fe23B6, within the cladding further contributed to the material's enhanced mechanical and wear properties.

Keywords

• Microwave cladding
• Interfacial bond layer
• Number of grains
• Hardness
• Corrosion
• Wear