Overzicht van aluminiumlegering 7075 poeder
Aluminium alloy 7075 powder is a precipitation hardening aluminum alloy that consists of aluminum, zinc, magnesium, copper, chromium, titanium, manganese, and other elements in minor amounts. It is considered one of the highest strength aluminum alloys and is widely used in applications that require high strength-to-weight ratio along with good fatigue strength.
Some key details about aluminium alloy 7075 powder:
- Composition – Aluminum base with zinc, magnesium, copper and other alloying elements
- Precipitation hardening type of alloy – Gets its strength from heat treatments
- Very high strength for its weight
- Good fatigue resistance and average machinability
- Common applications include structural parts, aircraft components, molds, etc.
- Available in various powder size ranges for use in additive manufacturing
Table 1: Composition of Aluminium Alloy 7075 Powder
| Element | Gewicht % |
|---|---|
| Aluminium | 87.1–91.4% |
| Zink | 5.1–6.1% |
| Magnesium | 2.1–2.9% |
| Koper | 1.2–2.0% |
| Ijzer | Max 0.5% |
| Silicium | Max 0.4% |
| Mangaan | Max 0.3% |
| Chroom | 0.18–0.28% |
| Titanium | Max 0.2% |
| Other metals | Each max 0.05% |
| Other impurities | Max 0.15% |
aluminium alloy 7075 powder Properties and Characteristics
Aluminium alloy 7075 powder offers an exceptional combination of high strength and low density. Some of its key properties and characteristics are:
Table 2: Properties of Aluminium Alloy 7075 Powder
| Eigendom | Details |
|---|---|
| Dikte | 2,81 g/cm3 |
| Smeltpunt | Around 635 to 655°C |
| Opbrengststerkte | 500 to 540 MPa |
| Treksterkte | 570 to 620 MPa |
| Verlenging bij breuk | 8 to 10% |
| Young-modulus | 71 to 72 GPa |
| Poission-ratio | 0.33 |
| Hardheid | Brinell 150 |
| Corrosieweerstand | Fair. Prone to pitting and intergranular corrosion |
| Slijtvastheid | Eerlijk |
| Warmtegeleiding | 120 to 130 W/m-K |
| Vermoeidheid Sterkte | 159 MPa |
Some additional characteristics of the 7075 aluminium powder:
- Excellent strength-to-weight ratio and high specific strength
- Good toughness and fatigue resistance
- Prone to stress corrosion cracking in certain tempers
- Susceptible to deterioration by elevated temperatures
- Machines easily in fully annealed state, poor machinability in hardened tempers
- Forging requires preheating; hot working must be done between 400-510°C
- Can be easily welded by gas welding, arc welding and resistance welding methods
Table 3: Applications and Uses of Aluminium Alloy 7075 Powder
| Gebied | Voorbeeldgebruik |
|---|---|
| Lucht- en ruimtevaart | Aircraft fittings, gears, shafts |
| Automobiles | Wheels, parts requiring high strength |
| Marien | Boat hulls, masts, propellers |
| Moulds | Plastic injection moulds, dies |
| Industrieel | Structural parts, bracing, bridges |
| Additieve productie | Printing high strength custom parts |
| Recreation | Mountain bikes, hang glider frames |
| Verdediging | Missile & rocket components |
| Elektronica | Base plates, motor parts, cooling fins |
Specificaties en kwaliteiten
Aluminium alloy 7075 powder is available under various standard specifications and tempers based on mechanical properties, heat treatment condition, etc.
Table 4: Specifications and Grades of Aluminium Alloy 7075 Powder
| Specificatie | Details |
|---|---|
| US Military Designation | 7075-T6, 7075-T651 etc. |
| ISO Specification | AlZn5.5MgCu |
| European Standards | EN AW-7075 / EN AW-AlZn6CuMgZr |
| ASTM Spec | ASTM B247, ASTM B211M |
| SAE Spec | AMS 4045, AMS 4154 |
| DIN | AlZn5,5MgCu |
| UNI | 56NiCrMo4 |
The common tempers include:
- F – As fabricated, no treatment
- O – Annealed state, lowest strength
- T6 – Heat treated and artificially aged to peak strength
- T651 – Stress relieved and artificially aged variant of T6
- Various other tempers available
Table 5: Size Ranges and Powder Sizes Available
| Poedergrootte | Microns | Mesh Tyler/ASTM |
|---|---|---|
| Atomized fine powder | 3-8 microns | n/a |
| Fine powder | 10-30 microns | -325 mazen |
| Coarse powder | 30-120 microns | -140 to -170 mesh |
| Very Coarse Powder | 120-250 microns | -60 to -120 mesh |
| Cut wire | Minder dan 150 micron | -100 mesh |
Leveranciers en prijzen
Aluminium alloy 7075 powder is readily available from many suppliers in various size ranges suitable for different additive manufacturing processes. Some example pricing ranges are given below for reference.
Table 6: Example Suppliers of Aluminium Alloy 7075 Powder
| Supplier (Example) | Beschrijving |
|---|---|
| LPW-technologie | UK based supplier of high quality aluminium alloy metal powders |
| Paul Müller GmbH | German supplier of aluminium and aluminium alloy powders |
| Erasteel | Global producer of specialty alloys and high purity products |
| Metal Fortress | US based supplier of aluminium alloy powders |
| Flawless Metal Powders | Chinese manufacturer of aluminium alloy powder |
Table 7: Example Pricing of Standard Grade Aluminium Alloy 7075 Powder
| Poedergrootte | Prijsklasse per kg |
|---|---|
| Fine Powder (10-30 μm) | $50 – $80 |
| Coarse Powder (30-120 μm) | $40 – $60 |
| Very Coarse Powder (120-250 μm) | $30 – $45 |
- Pricing varies based on quantity ordered, exact size ranges and supplier selected. May be higher for higher purity or special grades.
Vergelijking
Table 8: Comparison of 7075 Aluminium Alloy with other Aluminium Alloys
| Legering | Belangrijkste eigenschappen | Voordelen | Beperkingen |
|---|---|---|---|
| 7075 | Highest strength, good toughness, best fatigue strength, fair corrosion resistance | Very high specific strength, suited for critical applications, good wear resistance | Susceptible to SCC, easily corroded unless high purity, difficult to weld |
| 6061 | Medium strength, excellent corrosion resistance, good formability and weldability | Easier to machine and fabricate, most versatile | Not suited for high stress applications |
| 2024 | High strength, fatigue resistant, good toughness, poor corrosion resistance | High strength in thick sections, good fracture toughness | Prone to cracking, often requires cladding for corrosion protection |
| 5056 | Medium to high strength, excellent corrosion resistance, good weldability | Resists marine atmosphere and salt water corrosion, good cryogenic properties | Lower strength than 2xxx and 7xxx alloys |
Voordelen en beperkingen
Table 9: Advantages and Limitations of Aluminiumlegering 7075 poeder
| Voordelen | Beperkingen |
|---|---|
| Exceptionally high strength for critical applications | Relatief duur |
| Best strength-to-weight ratio among aluminium alloys | Susceptible to stress corrosion cracking |
| Excellent fatigue strength; good for cyclic loading | Poor corrosion resistance necessitates protection |
| Good toughness even in thick sections | Difficult to weld; requires preheating |
| Thick and complex sections can be 3D printed | Machining is difficult in hardened tempers |
| Used where steel would be too heavy | Mechanical properties degraded at high temperatures |
Veelgestelde vragen
Q: What makes 7075 aluminium alloy so strong compared to other aluminium alloys?
A: Alloy 7075 derives its exceptionally high strength from precipitation hardening heat treatments. Fine particles of transition phases like MgZn2 and Al2CuMg precipitate inside the aluminium matrix during aging and hinder dislocation motion, drastically increasing strength.
Q: Why is 7075 aluminium preferred for aerospace applications compared to other 2xxx or 6xxx alloys?
A: The 7075 aluminium alloy offers the best combination of high strength, good fracture toughness and excellent fatigue strength. This makes it well suited for demanding aerospace parts exposed to dynamic loads. It also offers higher strength in thick sections.
Q: Does aluminium alloy 7075 powder require any special storage or handling precautions?
A: Yes, aluminium alloy powders can be explosive if dispersed in air. Ensure proper grounding and venting during powder handling. Store sealed containers in cool, dry area away from sparks, flames and other ignition sources. Take standard precautions for handling fine metal powders.
Q: What are some examples of 7075 aluminium alloy powder applications in additive manufacturing?
A: Some common AM applications include printing lightweight aerospace and automotive components, high strength marine products like propellers, molds and dies for plastic injection molding, robotic arms, UAV components, mountain bike parts, etc.
Q: What size powder is preferred for DMLS 3D printing of aluminium alloy 7075 parts?
A: A particle size range of 15-45 microns is typically recommended for DMLS printing to enable good powder flow and high density. However, parameters depend on the specific 3D printer model and laser power.
