Laser surface-engineered vanadium carbide coating for extended die life

A successful effort has been made to deposit vanadium carbide on AISI H13 steel using Nd:YAG laser. In this study a continuous, adherent, crack-, and porosity-free coating has been obtained which can serve as a protective layer for various surfaces. The coating is composite in nature. To explore the properties of this coating in greater detail, it has been evaluated for chemical, structural, and mechanical properties. Another aspect of this work is to identify the suitability of this coating to protect die-casting die surfaces from the attack of molten aluminum. A number of different mechanisms, such as corrosive attack and erosion by molten aluminum and oxidation of the die surface, act to reduce the life of die-casting dies. In view of this, the coating has been tested for preliminary analysis such as high-temperature oxidation by conducting thermogravimetric analysis and for liquid metal corrosion resistance by immersion test in liquid aluminum. It shows excellent oxidation resistance below 600 °C and performs well in the immersion test in liquid aluminum by reducing the extent of attack of molten aluminum on the H13 steel.