Corson alloy
MAX251
C64725 (MAX251C)
Positioning map
Corson alloys have an excellent an excellent balance of strength and electrical conductivity
due to Ni -Si
intermetallic compounds precipitated in the matrix.
We have prepared the several MAX series according to application.
Main features
MAX251 CDA64725
MAX251 CDA64725
MAX251 has excellent properties of electrical conductivity, strength and workability, and also
that can be used as an alternative to phosphor bronze.
MAX251 has high electrical conductivity than other MAX sereis.
Positioning of Alloy
MAX251 is one of corson alloys developed by Mitsubishi Materials.
It has higher electrical conductivity than other MAX series and middle range strength.
Main features
- Excellent balance of strength,electrical conductivity and workability.
- Excellent heat resistance
- Small anisotropy of mechanical properties by our original technology.
- Possible to process reflow-Sn plating with excellent surface quality and whisker resistance
Chemical composition
(Weight %)
| Ni | Si | Sn | Zn | Cu |
|---|---|---|---|---|
| 2 | 0.5 | 0.5 | 1 | Rem. |
Physical properties
The physical properties of MAX251 are as follows.
| Property | Representative Value |
|---|---|
| Specific Gravity (293K) | 8.9 |
| Coefficient of Thermal Expansion (×10-6/K：293～573K) | 17.1 |
| Thermal Conductivity (W/(m・K)：293K) |
194 |
| Volume Resistivity (μΩm：293K) |
0.038 |
| Electrical Conductivity (%IACS:293K) | 46 |
| Modulus of Elasticity (kN/mm² : 293K) |
130 |
Mechanical properties (sampling direction :L.D.)
| Temper | |||||
|---|---|---|---|---|---|
| 1/2H | H | EH | SH | ESH | |
| Tensile Strength (N/mm²) |
450～550 | 500～600 | 540～640 | 600～700 | 700 min. |
| 0.2% Yield Strength (N/mm²) |
390～520 | 440～580 | 480～630 | 540～690 | 650 min. |
| Elongation (%) |
8 min. | 6 min. | 4 min. | 2 min. | - |
| Elastic Limit Kb0.1※1[kN/mm²] |
- | - | （400 min.） | （440 min.） | （470 min.） |
| Vickers Hardness※2 (HV) |
（125～185） | （140～200） | （150～215） | （165～230） | （200 min.） |
Stress relaxation resistance
MAX251 has excellent stress relaxation resistance than phosphor bronze(C5210) and brass (C2600).
Exposure temperature: 150℃
Sampling direction: Parallel to the rolling
direction
Bending stress: 80% of 0.2% yield strength
Fatigue properties
The fatigue characteristics of the MAX 251 meet the level required for springs and terminals.
MAX251C CDA64725
MAX251C CDA64725
The MAX 251C is a high-strength copper alloy which is further improved in properties by utilizing special heat treatment during the manufacturing process, not only improved in the strength but also reduced the anisotropy of the mechanical properties, and has the optimized balance between the strength and the bending workability. It has been developed for various applications due to its good workability.
Positioning of Alloy
The MAX 251C is a Corson alloy that has the improved strength and bending workability compared with conventional products through its own manufacturing process. It realizes further miniaturization of parts by obtaining the balance between the strength and the bending workability which is better than that of MAX 251. It is also possible to switch titanium copper with beryllium copper.
Main features
- Excellent in balance between strength · bending workability · conductivity
- Excellent thermal creep resistance
- Small anisotropy of mechanical properties due to special heat treatment
- Possible to process reflow-Sn plating with excellent surface quality and whisker resistance
Chemical composition
The chemical components of MAX251C are as follows.
(Weight %)
| Ni | Si | Sn | Zn | Cu |
|---|---|---|---|---|
| 2 | 0.5 | 0.5 | 1 | Rem. |
Physical properties
The physical properties of MAX251C are as follows.
| Property | Representative Value |
|---|---|
| Specific Gravity (293K) | 8.9 |
| Coefficient of Thermal Expansion (×10-6/K：293～573K) |
17.1 |
| Thermal Conductivity (W/(m・K)：293K) |
160 |
| Volume Resistivity (μΩm：293K) |
0.047 |
| Electrical Conductivity (%IACS:293K) |
37 |
| Modulus of Elasticity (kN/mm²: 293K) |
130 |
Mechanical properties (Sampling direction：L.D.)
The mechanical properties of MAX251C are as follows.
| Temper | Typical values | |||||
|---|---|---|---|---|---|---|
| 1/2H | H | EH | 1/2H | H | EH | |
| Tensile Strength (N/mm²) |
540～640 | 600～700 | 640～740 | 626 | 675 | 717 |
| 0.2% Yield Strength (N/mm²) |
480～630 | 540～690 | 580～735 | 554 | 584 | 663 |
| Elongation (%) |
8 | 5 | 3 | 17.3 | 14.8 | 11.4 |
| Elastic Limit Kb0.1※1[kN/mm²] |
- | - | - | （477） | （529） | （562） |
| Vickers Hardness※2 (HV) |
（150～215） | （165～230） | （180～240） | （187） | （199） | （211） |
| Electrical Conductivity [%IACS] |
33 min. | 40 | 38 | 38 | ||
Heat resistance
The MAX251C has sufficient heat resistance as a terminal material to be used at high temperatures.
Stress relaxation resistance
It shows that it has stress relaxation properties equal to or greater than beryllium copper and phosphor bronze for spring.
Exposure temperature: 150℃
Sampling direction: Parallel to the rolling
direction
Bending stress: 80% of 0.2% yield strength
Bending workability
The bending workability of the MAX251C is as follows.
While having high strength, it also has excellent bending workability. This can contribute to
miniaturization and improvement of reliability of parts.
| Temper | Sampling Direction | Bending Inside Radius (mm) R | Evaluation R/t | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| (to the rolling direction) | 0.0 | 0.1 | 0.125 | 0.15 | 0.2 | 0.25 | 0.4 | 0.6 | 0.8 | 1.0 | ||
| 1/2H | 0°:(Good Way) | △ | ○ | ○ | ○ | ○ | ○ | ◎ | ◎ | ◎ | ◎ | 0.0 |
| 90°:(Bad Way) | ○ | ○ | ○ | ○ | ○ | ○ | ◎ | ◎ | ◎ | ◎ | 0.0 | |
| H | 0°:(Good Way) | △ | △ | △ | △ | △ | △ | ○ | ◎ | ◎ | ◎ | 0.0 |
| 90°:(Bad Way) | ○ | ○ | ○ | ○ | ○ | ○ | ◎ | ◎ | ◎ | ◎ | 0.0 | |
| EH | 0°:(Good Way) | ▲ | ▲ | ▲ | △ | △ | △ | △ | ○ | ○ | ○ | 0.6 |
| 90°:(Bad Way) | ▲ | ▲ | △ | ○ | ○ | ○ | ○ | ◎ | ◎ | ◎ | 0.5 | |