In many applications Shape Memory Alloy (Nitinol) Wire provides actuation solutions that permit the elimination of solenoids and motors. SMA Actuators offer energy efficiency, lighter weight, space savings, cost savings and quiet operation while meeting the life cycling requirements of a wide variety of products.
Shape Memory Alloy Wire Motion Principle
The chart below shows typical Nitinol Alloy Wire performance characteristics based on set parameters. (Nitinol Wire Contracts .040 inches per inch) However, there are ways to improve response time, actuation range (movement), power requirements, etc.
| Nitinol Alloy Wire Performance Characteristics |
| Wire Size (Inches) |
Resistance (Ohms/Inch) |
Maximum Pull Force (grams) |
Applied Current at Room Temp (mA) |
Contraction Time (sec) |
Off Time 70°C Wire (sec) |
Off Time 90° Wire (sec) |
| 0.0010 |
45.0 |
7 |
20 |
1 |
0.10 |
0.06 |
| 0.0015 |
21.0 |
17 |
30 |
1 |
0.25 |
0.09 |
| 0.002 |
12.0 |
35 |
50 |
1 |
0.3 |
0.1 |
| 0.003 |
5.0 |
80 |
100 |
1 |
0.5 |
0.2 |
| 0.004 |
3.0 |
150 |
180 |
1 |
0.8 |
0.4 |
| 0.005 |
1.8 |
230 |
250 |
1 |
1.6 |
0.9 |
| 0.006 |
1.3 |
330 |
400 |
1 |
2.0 |
1.2 |
| 0.008 |
0.8 |
590 |
610 |
1 |
3.5 |
2.2 |
| 0.010 |
0.5 |
930 |
1000 |
1 |
5.5 |
3.5 |
| 0.012 |
.033 |
1250 |
1750 |
1 |
8.0 |
6.0 |
| 0.015 |
0.2 |
2000 |
2750 |
1 |
13.0 |
10.0 |
| 0.020 |
0.16 |
3562 |
4000 |
1 |
17.0 |
14.0 |
Information from Dynalloy, Inc.
Latching Shape Memory Alloy Actuator
| VOLTAGE IMPUT |
FORCE |
STROKE |
| 1.5/3 VDC |
100 g |
0.118 (3mm) |
Shape Memory Alloy Actuator provides a latched condition for alternate positions of a shaft with significant energy conservation making it especially ideal for battery driven devices. Testing shows potential of 1/10th power consumption vs. traditional latching solenoids. Interface can be designed to fit a wide variety of applications, especially for water valves.
- Power consumption reduced to .035 Watt-seconds from
.36 Watt-seconds.
- Battery life extended for product life.
Autosplice has developed a variety of custom SMA Actuator latch solutions for devices that require overall control of operation and/or accessibility.
The device below provides control and operation lockout by integrating two Shape Memory Actuators with electronic control of all functions. One SMA Actuator is integrated with a lever system to actuate the actual device, while the second SMA Alloy wire provides "latch" control and lockout until electronically released. This device also provides "burst control" in the actual application as well.
Custom SMA Actuator for latching/unlatching, releasing and device control
For this dispensing unit it was essential to develop a low profile release system. SMA Alloy wire eliminated the need for solenoids and increased the number of containers available in a given area, with flexible configuration management.
The Shape Memory Actuator opens the lid on programmable demand when access is required.
In addition to offering custom control that is difficult to match via traditional devices, Shape Memory Actuators also offer low cost, low power, generate less heat, are extremely lightweight and offer Quiet operation!
Discuss your latch release/latching applications with an Autosplice representative and take advantage of a Shape Memory Actuator solution for your device!
SMA Actuator dispensing unit