Aluminum alloy casings have become a standard core feature for magnetic-switch keyboards in the 2025–2026 period. Their value lies not merely in the “metal” itself, but in how the synergy of material rigidity, weight distribution, and surface finishing determines the keyboard’s bottom-out feedback, sound profile, and long-term stability. The market has clearly stratified: 6063 aluminum alloy—featuring CNC unibody construction and anodization—is the mainstream choice for mass-produced magnetic-switch keyboards, while 6061 and 7075 alloys are reserved for higher-end custom or flagship models.
I. Why Aluminum Alloy?
Choosing a keyboard casing material is essentially a balancing act between rigidity, weight, and cost. Plastic casings offer the lowest cost, but they undergo elastic deformation during typing; this absorbs the bottom-out feedback and traps the sound within the cavity, preventing it from projecting clearly. Aluminum alloy has a Young’s modulus far superior to plastic; the casing barely deforms during typing, resulting in “clean and crisp” bottom-out feedback and a sound profile characterized by clear metallic resonance.
Heat dissipation is another often-overlooked factor. Aluminum alloy has a much higher thermal conductivity than plastic, allowing it to rapidly conduct heat generated by the switches across the entire casing for dissipation. For magnetic-switch keyboards subjected to prolonged, high-load usage, this ensures more stable temperatures around the switches and slows the degradation of lubricant performance.
II. Alloy Selection: 6063 as the Mass-Production Standard
The 6063 alloy is currently the most widely used grade for aluminum casings in magnetic-switch keyboards. The entire Ajazz ALUX68 lineup comes standard with CNC-machined, anodized 6063 aluminum casings and side panels across various configuration tiers. MelGeek’s first high-performance, all-aluminum magnetic-switch keyboard similarly utilizes “6063 industrial aluminum profiles that exceed national standards,” emphasizing high strength and durability. The Darmoshark KT75, featuring a 180-grit anodized CNC aluminum body, follows this same approach.
The reason 6063 has become the preferred choice for mass production lies in the balance it strikes between machinability and surface finish quality. It offers superior machinability compared to the harder 6061 alloy, making it ideal for high-volume CNC processing, and it yields better color uniformity after anodization. 6061 alloy is used in applications requiring greater structural rigidity; it offers a tensile strength approximately 25% higher than 6063 but causes more tool wear during machining. 7075 aerospace-grade aluminum boasts strength far superior to the 6000 series, yet its high cost and machining difficulty limit its use to limited-edition or flagship custom products; it is rarely found in mass-produced magnetic-switch keyboards.
III. Manufacturing Processes: Distinctions Between CNC Machining, Die-Casting, and Profile Extrusion
The forming method for aluminum alloy cases directly determines both precision and cost.
-Pure CNC machining involves 3D milling from a solid aluminum billet using CNC machine tools; this achieves machining precision of ±0.02mm and a surface finish of Ra 0.8–1.6μm. Its advantages include extremely high precision and flexibility for design revisions, while its downsides are a high material removal rate (70–90%) and long per-unit processing times. Pure CNC remains the preferred choice for flagship products where ultimate precision is the goal.
-The “die-casting plus CNC” approach offers a more economical solution for mass production. Molten aluminum is first injected into a mold to rapidly form a rough blank, followed by CNC finishing of assembly surfaces and mounting holes. Die-cast blanks typically have tolerances ranging from ±0.07mm to ±0.127mm and may exhibit surface defects like porosity or shrinkage cavities; CNC finishing is essential to meet the assembly precision requirements of the keyboard case. This “cast-then-machine” strategy significantly reduces the CNC workload, striking a balance between cost, efficiency, and precision. Most mass-produced aluminum-cased magnetic-switch keyboards currently utilize this method.
-Profile extrusion followed by CNC machining represents a third manufacturing route. Aluminum ingots are heated and extruded through a die to form long profiles with a fixed cross-sectional shape; these are then cut into rough blanks matching the keyboard’s length, before finally undergoing CNC machining to refine assembly surfaces and hole locations. The extrusion die determines the casing’s fundamental cross-sectional profile—such as bezel thickness, slope angles, and the orientation of internal reinforcing ribs. This method offers higher material utilization than pure CNC machining and lower tooling costs than die-casting; however, it is limited to producing shapes with uniform cross-sections, meaning complex curved surfaces and intricate internal structures still require CNC processing. Some keyboards marketed with the “solid aluminum block” (or “aluminum slab”) concept utilize this approach to strike a balance between cost, weight, and tactile quality.
IV. Surface Treatment: The Combination of Sandblasting and Anodizing
The “tactile feel” and visual quality of an aluminum case derive from its surface treatment. The standard workflow is: sandblasting → anodizing → dyeing/sealing.
– Sandblasting involves high-speed projection of glass or zirconium beads onto the aluminum surface to create a uniform matte texture while masking tool marks left by CNC machining. 180-grit sandblasting is a common specification for magnetic-switch keyboards; models such as the Ajazz ALUX68 and Darmoshark KT75 explicitly list this parameter.
– Anodizing is the defining process for aluminum cases. When an aluminum part is immersed in a sulfuric acid electrolyte and subjected to an electric current, a dense aluminum oxide layer grows in situ on its surface. Type II anodic oxide films are approximately 8–12 μm thick and suitable for decorative purposes; Type III hard anodic oxide films are 35–50 μm thick, offering superior wear and corrosion resistance, though color options are limited—typically restricted to natural (uncolored) and black finishes.
Anodizing alters dimensions—since about 50% of the oxide layer “grows” outward, the design of precision housings must account for tolerances to accommodate the coating. Color variations may also occur between different batches or aluminum alloy materials post-anodizing; this is a critical quality control factor in mass production.
V. Market Segmentation: Process Differences Based on Positioning
The manufacturing processes for aluminum alloy housings vary widely. The Ajazz ALUX68 brings a CNC-machined 6063 aluminum housing with a 180-grit anodized finish down to an entry-level price point, demonstrating effective cost control for this process at scale. The Darmoshark KT75 features a 180-grit anodized CNC body, a ball-catch quick-release mechanism, and an 8kHz polling rate. Meanwhile, the IQUNIX EV63 EDG collaboration model—featuring a CNC aluminum body and an ultra-low front-edge design—targets the high-end esports market.
Differences in the same material across products with varying market positions stem primarily from CNC machining precision, the grit level of the surface finish, internal structural design (such as the complexity of implementing a Gasket mount), and the strictness of quality control standards. While aluminum alloy housings are no longer exclusive to high-end products, the ultimate tactile feel and quality of these “solid aluminum” keyboards are still determined by manufacturing precision.
