Úvod
2017 hliníková slitina — historically known as duralumin — is one of the earliest high-strength hliník alloys. It delivers competitive mechanical properties at a lower cost than 2024, but the trade-off is a narrower temper window and limited corrosion resistance. This guide covers where the alloy works, where it fails, and what to check before ordering.
Chemické složení
The 2017 system is Al-Cu-Mg-Mn, with copper as the primary strengthening element and magnesium contributing to the precipitation-hardening response. A typical composition range includes:
- Copper: 3.5–4.5%
- Magnesium: 0.4–0.8%
- Manganese: 0.4–1.0%
- Iron: ≤0.7%
- Silicon: 0.2–0.8%
- Zinc: ≤0.25%
- Titanium: ≤0.15%
- Balance: Aluminum
Klíčové vlastnosti
Strength and Hardness
In the T4 temper (solution heat-treated and naturally aged), 2017 reaches tensile strengths around 390–430 MPa with yield strength in the 220–260 MPa range. It falls between 6061-T6 and 2024-T4 in strength — stronger than standard structural aluminum but below the aerospace-premium 2xxx grades.
Obrobitelnost
2017 machines cleanly and produces well-broken chips. Tool wear is moderate and generally better than 6061, but not as forgiving as the lead-containing 2011 alloy. For high-volume production, cutting speed and coolant flow should be tuned to the T4 temper response.
Odolnost proti korozi
Like most 2xxx-series alloys, 2017 has limited corrosion resistance due to its copper content. Bare (unclad) 2017 is not recommended for marine, chemical, or outdoor exposure without protective coating. Alclad versions exist but are less common than for 2024.
Svařitelnost
Fusion welding is not recommended for 2017 — the alloy is susceptible to hot cracking and significant strength loss in the heat-affected zone. If joining is required, mechanical fastening or adhesive bonding is the safer route.
Tepelné zpracování
2017 is precipitation-hardenable. The standard T4 temper is achieved by solution treatment at approximately 495–505°C followed by quenching and natural aging. Artificial aging to T6 is possible but less common in practice because 2024 dominates that performance window.
2017 vs. Other Aluminum Alloys
2017 vs. 2024
2024 is a direct upgrade: higher strength (~470 MPa UTS in T4), better fatigue performance, and wider availability in aerospace-grade sheet and plate. 2017 is the budget option — suitable where the strength margin is not critical and cost sensitivity is higher.
2017 vs. 6061
6061-T6 offers better corrosion resistance and weldability but lower tensile strength (~310 MPa). Choose 2017 when strength matters more than weldability; choose 6061 when the part will be welded or exposed to the environment.
2017 vs. 7075
7075-T6 delivers approximately 50% higher tensile strength than 2017-T4 but gives up machinability and is significantly more expensive. 2017 occupies the mid-range: stronger than 6061, cheaper than 7075, and easier to machine than both 2024 and 7075.
Běžné stavy zpracování
- T4: Solution heat-treated and naturally aged to a stable condition. The most widely specified temper for 2017.
- T451: Solution heat-treated, stress-relieved by stretching, and naturally aged. Preferred when residual stress control matters for tight-tolerance machining.
- T6: Solution heat-treated and artificially aged. Less commonly specified for 2017 — 2024-T6 is the standard artificial-aged choice in the 2xxx family.
Go/No-Go Limits
Use this quick reference to decide whether 2017 fits your application.
Go — use 2017 when:
- Yield strength in the 220–260 MPa range is sufficient and cost is a primary constraint — 2017 is a more economical alternative to 2024. Typical applications: structural components, high-strength fasteners, precision-machined parts.
- Good machinability and chip breakage matter more than corrosion resistance — the part will run indoors or receive protective coating. Typical applications: machined fittings, bushings, tooling components.
- The project needs a heat-treatable 2000-series alloy but does not require fusion welding — 2017 is compatible with mechanical fastening and adhesive joining.
No-Go — do not use 2017 when:
- Welding is part of the fabrication plan — 2017 is not a weldable grade; switch to 2219 or consider 6061 for weldable structural work.
- Outdoor exposure or marine service is expected without cladding or protective coating — bare 2017 will corrode in wet or chloride-rich environments.
- Peak aerospace-grade fatigue performance is required — 2024-T3 or 7075-T6 are the standard options for primary aerospace structures.
- The specification demands artificial aging (T6) with known and reliable data — 2017-T6 specification data is less widely published than 2024-T62; verify availability early.
Aplikace
The Go/No-Go criteria above cover selection logic. The list below maps specific systems where 2017 is used:
- Aerospace — secondary structural components, aircraft fittings, rivets
- Automotive — high-strength machined parts, suspension components, fasteners
- General engineering — precision-machined tooling, bushings, mechanical parts
- Defense — ordnance components, structural parts with moderate corrosion requirements
Závěr
2017 aluminum is a mid-range 2xxx alloy that bridges the gap between 6061 and 2024 — stronger than standard structural aluminum, cheaper than aerospace 2024, and easier to machine than 7075. The trade-off is limited corrosion resistance and no weldability, which means it fits indoor, machined-component applications best.
Linsy Aluminum supplies 2017 in plate, bar, and tube, with custom dimensions available at low minimum order quantities. MTC documentation is included with every order, and SGS testing is available on request. Send the drawing for a grade-fit review.
Často kladené otázky
What makes 2017 different from 2024?
2024 has higher strength (~470 MPa UTS in T4 vs. 2017’s ~430 MPa) and better fatigue performance. 2017 is the more economical option — its strength is still well above 6061, and machinability is slightly better than 2024. The choice usually comes down to whether the extra strength margin of 2024 is worth the cost.
Can 2017 be used in marine environments?
Not without cladding or protective coating. The copper content that gives 2017 its strength also makes it susceptible to galvanic corrosion in saltwater. For marine applications, 5083, 5086, or 6061 with appropriate surface treatment are better choices.
Does 2017 require special machining parameters?
It machines well with standard aluminum tooling, but surface speed should be checked against the T4 temper response. Chip evacuation is generally good, and built-up edge is less of an issue than with gummier 5000-series alloys. Coolant is recommended for high-volume runs to control thermal expansion.
Is 2017 available in sheet form?
Standard plate and bar forms are more common, but sheet may be available depending on the temper and thickness. Contact the supplier with the specific gauge and temper requirement to check current stock or custom production lead times.
What certifications or test reports are available for 2017?
MTC (Mill Test Certificate) documenting chemical composition and mechanical properties is standard for every order. Third-party SGS reports for chemical composition, mechanical properties, and dimensional inspection are available on request at additional cost.
