Aluminum Buyer's Guide: Grades, Shapes & When to Use It Over Steel

If you've been buying steel for years and haven't seriously considered aluminum for parts of your project, you might be leaving money on the table — or adding weight and maintenance costs you don't need. Aluminum isn't a replacement for steel. It's a different tool for different jobs, and knowing when to reach for it can save you real headaches down the road.

Why Aluminum Deserves a Spot in Your Material Plan

Aluminum weighs about 40% as much as steel. That's the headline number, and it matters more than most people think. A 100-pound steel bracket redesigned in aluminum drops to roughly 40 pounds — which means cheaper shipping, easier installation, and less structural load on whatever it's mounted to.

But weight is just the start. Aluminum naturally forms a thin oxide layer that protects it from corrosion without paint, primer, or galvanizing. In Oregon's wet climate, that's a real advantage for outdoor applications where you'd otherwise be fighting rust every few years.

Here's where aluminum makes the most sense:

Weight-sensitive builds — trailers, truck bodies, mobile equipment, ramps, platforms
Corrosion-prone environments — outdoor signage, marine hardware, HVAC ducting, food processing equipment
Architectural and decorative work — railings, trim, storefronts, window frames
Electrical applications — aluminum conducts electricity at about 60% the rate of copper, at a fraction of the weight and cost

When Steel Is Still the Better Call

Aluminum isn't trying to be steel. For heavy structural work — beams, columns, load-bearing frames — steel's superior strength and lower cost per pound make it the clear winner. If you need to understand steel options, our guide to steel grades (A36, A572, 1018, 4140) breaks down the most common choices.

Stick with steel when:

Maximum strength matters more than weight — structural framing, heavy equipment, bridges
Budget is tight on large-volume orders — steel is roughly 30–50% cheaper per pound than aluminum
High-temperature service — aluminum loses strength faster than steel above 400°F
Weldability is critical — steel welding is more forgiving; aluminum welding requires TIG, clean prep, and more skill

Common Aluminum Grades and What They're For

Not all aluminum is the same. The alloy grade determines strength, corrosion resistance, weldability, and machinability. Here are the grades you'll run into most often:

3003 — The General-Purpose Workhorse
Good formability, good corrosion resistance, moderate strength. Used for roofing, siding, HVAC ducting, storage tanks, and cooking equipment. If you need sheet or plate for bending and forming and don't need high strength, 3003 is your go-to.

5052 — Marine and Welding Grade
Excellent corrosion resistance, especially in saltwater. Higher fatigue strength than 6061. Great for welding. Used for marine components, fuel tanks, hydraulic tubing, and anything heading to the Oregon coast. If you're fabricating parts that will be welded and exposed to moisture, 5052 is hard to beat.

6061 — The Structural Standard
The most widely used structural aluminum alloy. Good strength, machinability, and weldability. Heat-treatable. Used for truck frames, trailer beds, structural braces, equipment frames, and recreational products. When someone says "structural aluminum," they usually mean 6061.

6063 — The Architectural Choice
Similar to 6061 but optimized for extruded shapes and surface finish. Used for window and door frames, railings, signage, pipe, and tubing. If appearance matters and you're working with extruded profiles, 6063 gives you a cleaner finish.

Aluminum Shapes We Stock

We carry aluminum in every common shape, ready for pickup or free next-day delivery:

Angle — structural bracing, frames, trim
Flat bar — machine parts, supports, fabrication stock
Hex bar — precision machining, fastener stock
Round rod — shafts, pins, spacers
Square bar — frames, brackets, supports
Channel — structural framing, conveyor systems
Expanded sheet — walkways, guards, ventilation screens
Pipe — irrigation, structural, conduit
Plate — trailer decking, machine bases, structural panels
Tread plate — ramps, platforms, truck beds, non-slip flooring
Sheet — HVAC, panels, enclosures, sign blanks
Rectangular tube — frames, railings, structural members
Round tube — handrails, roll cages, structural supports
Square tube — frames, furniture, architectural features

If you need any of these cut to size, we offer laser cutting, plasma cutting, saw cutting, shearing, and forming in-house. That means you get material and processing from one source with one delivery — no chasing multiple vendors.

Aluminum Pricing: What to Expect in 2026

Aluminum prices have been rising. LME aluminum averaged around $2,900 per metric ton heading into 2026, with analysts forecasting prices could exceed $3,000/ton through the year. Global supply deficits of roughly 200,000 metric tons are tightening the market, and U.S. regional premiums have climbed above $1 per pound — the highest on record for the domestic market.

For buyers, that means:

Lock in pricing early — request a quote as soon as you know your material list rather than waiting
Buy what you need now — prices aren't trending down in the near term
Consider volume commitments — larger orders give us more room to work on pricing
Don't overbuy gauge or alloy — a common mistake is specifying 6061 plate when 3003 sheet would do the job at lower cost

Current tariffs also apply to aluminum imports. Our post on how steel and aluminum tariffs are affecting prices in 2026 covers the details and tips for keeping your project on budget.

How to Choose: Steel, Aluminum, or Both

Most of our customers use both metals across different parts of a project. Here's a quick framework:

Does it need to be light? Trailers, portable equipment, overhead structures → aluminum.
Will it live outdoors in moisture or salt air? Signage, coastal structures, food equipment → aluminum (or stainless steel — see our 304 vs 316 guide).
Is it purely structural and cost-driven? Beams, columns, heavy frames → hot rolled steel.
Does it need a clean finish without painting? Architectural trim, railings, storefronts → aluminum 6063.
Is welding critical and the fabricator less experienced with aluminum? → Steel is more forgiving.

Get Aluminum from Ram Steelco

We've been supplying metal to Oregon since 1938 — and aluminum has been a growing part of what we do. When you order from us:

Full aluminum inventory in angle, bar, tube, pipe, plate, sheet, and tread plate
In-house processing — cut, sheared, or formed to your spec, same as our steel
Free next-day delivery across Oregon
One source for steel, aluminum, stainless, and galvanized — simplify your supply chain
Real answers from people who understand both materials and can help you spec the right one

Ready to order? Request a quote online or call us at 503.588.1311. Not sure whether aluminum or steel is right for your application? Contact us and we'll help you figure it out.

Ram Steelco has been Oregon's trusted steel and metals supplier since 1938, offering carbon steel, stainless steel, aluminum, and galvanized products with full in-house processing and free next-day delivery.