högkrom

Högkrom is a Swedish term used in metallurgy to describe alloys with high chromium content. In practice, the label covers several families, notably high-chromium stainless steels and high-chromium white cast irons, which are valued for wear and corrosion resistance. The term functions descriptively rather than as a single standardized material grade.

Composition and microstructure: In stainless steels, chromium content typically exceeds 10.5%, often in the 12–30% range, and is frequently balanced with nickel, molybdenum and other elements to optimize corrosion resistance and mechanical properties. High-chromium cast irons contain roughly 12–40% chromium and about 2–5% carbon; chromium promotes carbide formation, creating a hard, wear-resistant matrix that is, however, more brittle than some other steels.

Properties: Higher chromium content generally improves corrosion resistance in stainless varieties and enhances wear resistance in carbide-rich irons. The trade-offs can include reduced machinability, increased brittleness in some high-chromium cast irons, and higher material cost. Heat treatment and alloy composition strongly influence toughness, hardness, and stability of the passive film in stainless grades.

Applications: Högkrom materials are used in environments with severe wear or corrosive conditions. Common applications include mining and mineral processing equipment (crushers, hammers, wear plates, grinding media), cement industry components, and tools or dies requiring high hardness and resistance to abrasion.

Production and processing: These alloys are produced through conventional steelmaking with ferrochromium additions and subsequent processing. Stainless grades may undergo solution treatment and aging, while carbide-rich irons rely on controlled solidification and heat treatment to optimize carbide structure.

See also: Stainless steel, high-chromium steel, white cast iron, abrasion resistance.