Some Common Knowledge About Magnesium Plate Hot Rolling Mills

Magnesium board Hot rolling mill Its function is to perform hot rolling on magnesium alloy ingots in accordance with production process requirements, complete the rolling of sheet products, and subsequently produce qualified intermediate billets and finished sheets. The installation level of the hot rolling mill—such as its process design philosophy, equipment configuration, and control accuracy— It directly determines the mechanical properties, dimensional tolerances, and surface quality of magnesium sheet products.

The hot-rolling process and its control for magnesium sheets pose significant challenges in the field of conventional structural metallic materials. In both the production process and the design calculations for hot-rolling mills, it is not possible to apply the standard formulas used for rolling steel, copper, or aluminum—metals with distinct crystal structures. Consequently, designing a hot-rolling mill based on an analysis of the magnesium sheet hot-rolling process becomes particularly critical.

Hot-rolling mill manufacturers identify numerous factors contributing to the challenges of magnesium‑plate production, but the primary issue is magnesium’s limited slip systems and poor room‑temperature ductility. Only when the temperature rises above 220°C can magnesium alloy sheets achieve adequate formability. During rolling, magnesium plates are prone to cracking, exhibit pronounced anisotropy, and suffer from low production efficiency and a low yield of finished products.

Hot rolling mill Manufacturers identify the technical challenges of hot rolling magnesium alloy sheets as follows: Magnesium has a hexagonal close‑packed crystal structure, resulting in pronounced anisotropy in its mechanical properties. At room temperature, it possesses only three slip systems—basal, prismatic, and pyramidal—with a single slip direction, leading to high deformation resistance during processing and making the production of magnesium sheets particularly difficult. Moreover, magnesium readily reacts with air and water vapor under ambient or humid conditions; at temperatures exceeding 400°C, its reaction with oxygen becomes vigorous, forming an oxide scale that is both porous and thick, which rapidly grows into the bulk material. Consequently, the rolling temperature for magnesium sheets must be tightly controlled, with a narrow operating window, rapid thermal cooling, high strain‑hardening tendencies, and significant work hardening. In addition, excessively high reduction per pass or overly fast rolling speeds not only hinder the bite‑in of the hot‑rolled billet but also increase the likelihood of roll cracking, poor surface quality, and adhesion between the billet and the rolls.

Hot‑rolling mill manufacturers contend that domestic magnesium‑plate producers are small in scale, geographically dispersed, and relatively weak in overall competitiveness; even some large state‑owned enterprises primarily engage in ancillary processing. In terms of production processes and equipment, most facilities rely on rolling lines originally designed for steel, aluminum, copper, or titanium sheets, or on “two‑person‑per‑mill” setups—some of which are equipment dating back to the 1960s, now nearing obsolescence—while dedicated magnesium‑plate production lines remain scarce. During hot‑rolling operations, finishing steps such as straightening and shearing are typically performed offline.

Foreign countries Hot rolling mill Magnesium sheet products produced through ingot rolling and billet opening are predominantly medium‑ and thick‑gauge plates, primarily used in the aerospace and military equipment sectors. In contrast to domestic applications, where magnesium sheets are mainly employed for simple, non‑load‑bearing or lightly loaded structural components—such as instrument panel bulkheads, rib and partition structures in missiles and rockets, tail fins on missiles and aircraft, auxiliary fuel tanks, and fighter‑aircraft linings—foreign‑produced magnesium sheets are also utilized in large, complex, and load‑bearing structural parts.