Introduction to steel fiber

Steel, among which cut steel fiber is widely used and has high tensile strength. Cut steel fiber produced by cold drawing technology at the temperature below the metal crystal temperature with low carbon alloy as the substrate has a tensile strength of 1150-3000MP. It is widely used in industrial floor (logistics, cold storage, outdoor, storage) reinforcement and cracking improvement.
Fibers with an aspect ratio (ratio of fiber length to its diameter, when the fiber cross section is non-circular, the diameter of the equivalent cross-sectional circular area is converted) of 30 to 100 are made by cutting fine steel wire, shearing cold-rolled strip steel, milling ingots or rapid condensation of molten steel. The properties of steel fibers vary greatly due to different preparation methods, such as the tensile strength of cold-drawn steel wire is 380-3000MPa, the tensile strength of cold-rolled strip steel shearing method is 600-900MPa, and the tensile strength of ingot milling method is 700MPa; although the molten steel condensation method is 380MPa, it is suitable for the production of heat-resistant fibers.
Fine steel wires with a certain length and diameter range added to reinforce mortar or concrete. Long straight steel fibers with a circular cross section are commonly used, with a length of 10 to 60 mm, a diameter of 0.2 to 0.6 mm, and an aspect ratio of 30 to 100. In order to increase the interfacial bonding between the fiber and the mortar or concrete, various special-shaped steel fibers can be selected, including rectangular, serrated, crescent-shaped cross sections; cross-sectional dimensions that alternate along the length; wavy; circular; enlarged ends or with hooks, etc.
In order to make the steel fibers more evenly dispersed in the mortar or concrete and increase the aspect ratio of the fibers, steel fibers bonded together into bundles by water-soluble glue can be used. Steel fibers can be manufactured by cutting cold-drawn steel wire, shearing thin steel plates, milling steel blocks or ingots, and drawing molten steel. Low-carbon steel fibers can be used to prepare steel fiber concrete for use at room temperature; while stainless steel fibers must be used to prepare fire-resistant steel fiber concrete. Adding an appropriate amount of steel fiber to mortar or concrete can increase its tensile and flexural strength, and greatly improve its toughness and impact resistance.