ECOMASHINAROI Lead-Free Free-Machining Aluminum Alloys
For realizing lead-free automobiles and electrical equipment
To address growing demand for lead-free automobiles and electrical equipment, UACJ supplies the lead-free aluminum alloy ECOMASHINAROI. Lead is typically added to aluminum alloy to enhance scrap processability, but in recent years its use has been restricted due to environmental concerns.
Features
- Machinability
CB156 is an ideal substitute for alloy 2011, which contains lead.
CB256 is designed for use in environments where temperatures are 100˚C or above and is effective as a substitute for alloy 2017. - Chip treatability
CB156 offers the same machinability as alloy 2011, which has had lead added.
CB256 demonstrates superior chip treatability to alloy 2017. - Mechanical properties
CB156 and CB256 offer strength that is close to that of alloy 2011.
* Depending on the usage environment, there are some cases where the use of lead-free free-machining alloys is not appropriate. Please discuss this with us in advance. - Alumite treatability
GT209 offers superior alumite treatability at the same level as AA6.
Chemical Composition
| Si | Fe | Cu | Mn | Mg | Cr | Zn | Ti | Pb | Bi | Sn | Al | Remarks | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| CB156 | 0.4 or less | 0.7 or less | 4.5–6.0 | - | - | - | 0.3 or less | - | - | Bi+Sn= 0.9–2.3 |
bal. | Lead-free, tin added | |
| CB256 | 0.4 or less | 0.7 or less | 4.5–6.0 | - | - | - | 0.3 or less | - | - | 0.6–1.8 | - | bal. | Lead-free, tin-free |
| 2011 | 0.4 or less | 0.7 or less | 5.0–6.0 | - | - | - | 0.3 or less | - | 0.2–0.6 | 0.2–0.6 | - | bal. | Lead added |
| 2017 | 0.2–0.8 | 0.7 or less | 3.5–4.5 | 0.4–1.0 | 0.4–0.8 | 0.1 or less | 0.25 or less | 0.15 or less | - | - | - | bal. | Material in general use |
Performance
Mechanical properties
Types and mechanical properties of aluminum alloys for use in free machining
| Alloy series | Material temper | Lead content (% of mass) |
Mechanical properties | Chip treatability | Surface treatability | Corrosion resistance | Toughness at high temperatures | ||
|---|---|---|---|---|---|---|---|---|---|
| Tensile strength (N/mm2) |
Yield strength (N/mm2) |
Elongation (%) |
|||||||
| 2000 series lead-free material | CB156-T8 | - | 420 | 320 | 15 | ◎ | △ | △ | 〇–△ |
| CB256-T8 | - | 440 | 330 | 15 | 〇 | △ | △ | ◎ | |
| 2000 series traditional material | 2011-T8 | 0.6 | 440 | 330 | 15 | ◎ | △ | △ | 〇 |
| 2017-T4 | - | 440 | 275 | 20 | △ | △ | △ | ◎ | |
| 6000 series lead-free material | GT209-T6 | - | 310 | 270 | 14 | ◎ | ◎ | 〇 | 〇 |
*◎: Extremely good 〇: Good △: Fairly poor ×: Poor
Chip treatability
External appearance of chips after machining