The aluminum alloy doors and windows, mobile phone cases, aluminum cans, and even airplane wings we encounter every day, all seem to be made of "aluminum," but in reality, they are diverse in type and have vastly different uses. Among them, "wrought aluminum," as the "all-rounder" of the aluminum family, permeates every aspect of industrial production and daily life.
Many people confuse "wrought aluminum" with ordinary aluminum materials. Today, we'll clarify everything: What exactly is wrought aluminum? And what are some common aluminum materials around us?
01
Wrought aluminum, what exactly is "wrought"?
Simply put, wrought aluminum (wrought aluminum alloy) is an aluminum alloy that has undergone various plastic deformation processes to produce sheets, bars, profiles, or forgings. Its core characteristics are "shapeability and high strength," distinguishing it from cast aluminum, which is directly cast into shape.
Its "birth process" is like "forging iron into a useful object": first, aluminum ingots are melted and cast into billets. After homogenization, they are repeatedly processed through rolling, extrusion, drawing, and forging to ultimately become the various shapes we need-such as rolling thin sheets for beverage cans, extruding profiles for doors and windows, and forging forgings for aircraft parts.
Having said all that, let's introduce the three core advantages of wrought aluminum:
· Lightweight: With a low density, only about 1/3 that of steel, it can reduce product weight while maintaining structural strength, making it a "weight-saving marvel" in the aerospace and automotive industries.
· Easy to process: Excellent plasticity allows it to be made into complex shapes through various deformation processes. It can also undergo heat treatments such as annealing and quenching to flexibly adjust its properties.
· Multiple advantages combined: Good electrical and thermal conductivity, strong corrosion resistance, and some models, after strengthening treatment, can even rival the strength of steel, making them suitable for various complex applications.
Here's a crucial point to distinguish: the core difference between wrought aluminum and cast aluminum lies in their "forming method"-cast aluminum is "liquid-state forming" (like pouring cement, molten aluminum is poured into a mold to cool and solidify), suitable for making parts with complex shapes but low strength requirements (such as engine blocks); wrought aluminum is "solid-state forming," suitable for structural components requiring high strength and high plasticity (such as aircraft wings and car bodies).
02
The wrought aluminum family is divided into two categories with significantly different uses
The wrought aluminum family is vast, and based on whether it can be strengthened through heat treatment, it can be divided into two main categories:
1. Wrought aluminum that cannot be heat-treated: This material is relatively soft, corrosion-resistant, and commonly used in everyday applications.
These types of wrought aluminum primarily rely on solid solution strengthening and cold deformation strengthening to enhance their strength. Their core advantages are good plasticity and strong corrosion resistance, but their strength is relatively low. They are suitable for products that do not require high strength but demand easy processing and corrosion resistance. Common types include:
* Aluminum-manganese alloys: A typical example is LF21 (Chinese marking). They have excellent corrosion resistance and good plasticity, and are commonly used to manufacture beverage cans, cooking utensils, and roofing panels. Many of the aluminum cans we drink are made from this type of aluminum.
* Aluminum-magnesium alloys: These have higher strength than aluminum-manganese alloys, reaching over 300 MPa, and strong corrosion resistance, making them particularly suitable for marine environments. They are widely used in welded structures, such as dump truck bodies, oil storage tanks, small ship hulls, and some components in architectural decoration.
2. Heat-treatable wrought aluminum: High hardness.
These types of wrought aluminum alloys primarily enhance their strength through precipitation hardening (aging hardening), resulting in strengths far exceeding those of the former. Some models are used in high-end industrial applications. Common types include:
* **Aluminum-copper/aluminum-copper-magnesium (duralumin):** Marked as LY, a typical example is LY12 (corresponding to the international 2024 alloy). With a tensile strength reaching 470-480 MPa, its high strength makes it a common choice in the aerospace industry, used to manufacture aircraft fuselages, wings, and other structural components. It is also used in some high-strength mechanical parts.
* **Aluminum-magnesium-silicon:** The most commonly used medium-strength alloy, marked as LD, a typical example is LD1 (corresponding to the international 6063 alloy). It has good weldability and corrosion resistance, and is easy to surface treat (such as anodizing). It is a mainstay in building profiles, essential for doors, windows, curtain walls, and furniture.
* Aluminum-zinc-magnesium-copper alloy (super-hard aluminum): Marked as LC, a typical example is LC9 (corresponding to the international 7075 alloy). Its tensile strength can reach 540-570 MPa, exhibiting extremely high strength. It is mainly used in aerospace and military fields, such as aircraft landing gear and high-strength structural components.
Besides wrought aluminum, there are many other common aluminum materials around us, with different forms and uses. After researching online, we've compiled a list of four of the most commonly encountered aluminum materials. Let's take a look.
03
Not just wrought aluminum! These aluminum materials are also common in daily life
1. Pure aluminum: The most basic type of aluminum, soft but useful.
High purity (usually above 99%), excellent electrical and thermal conductivity, but low strength. Good plasticity, mainly used in the manufacture of wires, cables, and insulation materials, as well as commonly used aluminum foil (food packaging, kitchen foil). Some pure aluminum is also used in simple daily necessities.
2. Cast aluminum: Capable of complex shapes, high cost-effectiveness.
The "liquid-formed" aluminum material mentioned earlier has a high silicon content (7%~25%), good fluidity, and can be easily molded into complex shapes, such as automobile engine blocks, gearbox housings, wheel hub blanks, and some small mechanical parts. Its low cost and fast forming speed make it a cost-effective choice in the industrial field.
3. Aluminum Profiles: The first choice for doors, windows, and curtain walls; a necessity.
Mostly belonging to the aluminum-magnesium-silicon alloy (6063 alloy) in wrought aluminum, they are made through extrusion molding, with various cross-sectional shapes (flat, channel, and round tubes, etc.). They are widely used in building doors and windows, curtain walls, railings, as well as industrial equipment supports and frames, and even decorative components for furniture and home appliances. The aluminum alloy doors and windows commonly seen in our homes are the most typical aluminum profiles.
4. Aluminum Sheets/Foils: Found in every household; widely used.
Aluminum sheets are rolled from wrought aluminum. Different thicknesses have different uses; thin aluminum sheets are used for car bodies and building roofs, while thicker sheets are used for pressure vessels. Aluminum foil is an ultra-thin cold-rolled aluminum product with good sealing and corrosion resistance. Besides food packaging, it is also used in pharmaceutical packaging and shielding materials for electronic products, such as aluminum foil packaging for pills and shielding foil inside mobile phones.
Wrought aluminum is not a "single type of aluminum," but a general term for "workable aluminum alloys." With its high strength, lightweight, and ease of processing, it supports a significant portion of the industry in aerospace, construction, and automotive sectors. Meanwhile, pure aluminum, cast aluminum, and aluminum profiles also play their respective roles in different applications.
Next time you see aluminum alloy products, try to distinguish whether it's a wrought aluminum profile or a cast aluminum part. After reading this, you too can become an "aluminum expert."
