This course provides an overview of Ni-Hard alloys, a family of white cast irons alloyed with nickel and chromium to achieve high hardness, excellent abrasion resistance, and reliable performance in demanding industrial environments. It explains their chemical composition, microstructure, mechanical properties, and wear behavior, and describes how different grades of Ni-Hard are produced through controlled melting, molding, alloying, and heat-treatment practices. It also highlights typical applications, such as pumps, mining equipment, grinding components, and other parts exposed to heavy abrasion and impact. Through practical examples, figures, and engineering guidelines, the document serves as a technical reference for understanding and applying Ni-Hard cast irons in real industrial settings.