A mini desktop impact test system using multistage electromagnetic launch

• A mini desktop impact test system using multistage electromagnetic launch was developed.
• The principle of eliminating the electromagnetic effect in strain signal was described.
• The validation tests on aluminum alloy for impact compression test system were carried out.
• The validation tests on polyimide/SiO2 film for impact tension test system were carried out.

A miniaturized Split Hopkinson Bar (SHB) system has been developed based on electromagnetic launch. The novel and simple multistage electromagnetic launch technique has been investigated for being against the drawback of traditional pneumatic loading system, such as the need for very-high air pressures, lack of test repeatability, high operation noise, large size, and large overall weight of the apparatus. The easy and practicable multistage electromagnetic launch device and its working principle are described in details. A simple launch speed calibration technique, methods of eliminating the electromagnetic signal effect and erasing magnetism in bars are also described. With the same multistage electromagnetic launch device and main components, the system could be switched between impact compression and tension modes for mini specimen testing easily. Successful validation tests on aluminum alloy for impact compression and polyimide/SiO2 film for impact tension were carried out for verifying the feasibility and reliability of the system.