Main Menu

See All Software See All Instruments See All Transducers See All Vibration Testing Equipment See All Electroacoustics See All Acoustic End-of-Line Test Systems See All Academy See All Resource Center See All Applications See All Industries See All Services See All Support See All Our Business See All Our History See All Global Presence

Main Menu

See All Analysis & Simulation Software See All DAQ Software See All Drivers & API See All Utility See All Vibration Control See All High Precision and Calibration Systems See All DAQ Systems See All S&V Hand-held Devices See All Industrial Electronics See All Power Analyzer See All S&V Signal Conditioner See All Acoustic Transducers See All Current and Voltage Sensors See All Displacement Sensors See All Force Sensors See All Load Cells See All Multi Component Sensors See All Pressure Sensors See All Strain Sensors See All Strain Gauges See All Temperature Sensors See All Tilt Sensors See All Torque Sensors See All Vibration See All Accessories for Vibration Testing Equipment See All Vibration Controllers See All Measurement Exciters See All Modal Exciters See All Power Amplifiers See All LDS Shaker Systems See All Test Solutions See All Actuators See All Combustion Engines See All Durability See All eDrive See All Production Testing Sensors See All Transmission & Gearboxes See All Turbo Charger See All Training Courses See All Acoustics See All Asset & Process Monitoring See All Custom Sensors See All Durability & Fatigue See All Electric Power Testing See All NVH See All Reliability See All Vibration See All Weighing See All Automotive & Ground Transportation See All Calibration See All Installation, Maintenance & Repair See All Support Brüel & Kjær See All Release Notes See All Compliance

Main Menu

See All nCode - Durability and Fatigue Analysis See All ReliaSoft - Reliability Analysis and Management See All API See All Experimental Testing See All Electroacoustics See All Noise Source Identification See All Environmental Noise See All Sound Power and Sound Pressure See All Noise Certification See All Industrial Process Control See All Structural Health Monitoring See All Electrical Devices Testing See All Electrical Systems Testing See All Grid Testing See All High-Voltage Testing See All Vibration Testing with Electrodynamic Shakers See All Structural Dynamics See All Machine Analysis and Diagnostics See All Dynamic Weighing See All Vehicle Electrification See All Calibration Services for Transducers See All Calibration Services for Handheld Instruments See All Calibration Services for Instruments & DAQ See All On-Site Calibration See All Resources See All Software License Management

Split-Hopkinson Bar Material Tests



Split Hopkinson bar testing is a method in materials testing that enables material properties to be determined in dynamic conditions.


How does a Split-Hopkinson Test work?

Split-Hopkinson bar testing is a tried and tested method in materials testing. Unlike quasi-static testing machines a split-Hopkinson bar enables material properties to be determined in dynamic conditions. The method involving the use of a split-Hopkinson bar enjoys increasing popularity in many applications thanks to ever more powerful test and measurement technology.
A split-Hopkinson bar is used to dynamically determine material constants, for example Young's modulus or mechanical stress. Young's modulus is a material constant that is a measure for how much a component is deformed when a force is applied to it. British electrical engineer Bertram Hopkinson first suggested such measurements in 1914. The setup used today is based on a modification developed by Herbert Kolsky in London in 1949. It is sometimes also called split-Hopkinson Kolsky bar. The material sample is positioned between two bars in the split Hopkinson bar: the incident bar and the transmission bar. A so-called striker - for example, a projectile accelerated by compressed air - strikes the incident bar causing an elastic wave pulse. This elastic wave pulse runs through the first bar. Part of the pulse is reflected at the bar end, the other part runs through the material sample into the transmission bar. Strain gauges (SG) installed on the surfaces of the incident bar and the transmission bar measure the strains caused by the elastic wave pulse. The strain gauges enable the amplitudes of the elastic wave pulse applied to the incident bar, the reflected pulse and the transmitted pulse to be determined.

Requirements of test and measurement technology

Which requirements does test and measurement technology neet to meet when a split-Hoplinson bar is used? Successful use of a split-Hopkinson bar requires strain gauges installed on the surfaces of both the incident bar and the transmission bar and, in addition, a powerful data acquisition system. This is confirmed by latest research findings: „Generally speaking, the minmum frequency response of all the components in the data acquisition system should be 100 kHz. (Cheng / Song, Split Hopkinson Bar, S. 9)”. The Genesis HighSpeed series offered by HBM Test and Measurement is the perfect data acquisition system for use on a split-Hopkinson bar. In addition, HBM provides you with strain gauges developed and produced 'in-house' for installation on a split-Hopkinson bar.

Video: Taking a split-Hopkinson bar measurement

An Introduction to Split-Hopkinson Bar Testing and Dynamic Strain Measurements

How does it differ from a static material testing machine?

What is the difference between using a split-Hopkinson bar and a static material testing machine? Young's modulus is usually determined from a stress-strain-curve created in a testing machine under quasi-static conditions - i.e. with (very) small strain rates. However, material behavior may differ substantially with dynamic loads. Depending on whether dynamic loads, too, occur in a structure, the design engineer needs to know the material's dynamic properties as well. Normally a simple material testing machine is not able to apply the required high strain rates.

Do you need more information?

A comprehensive explanation of the functioning and use of a split-Hopkinson bar is given in the reverence book by Weinong Chen, Bo Song: Split Hopkinson (Kolsky) Bar- Design, Testing and Applications. Read excerpts of the book on Google books. You can also contact Bundesanstalt für Materialprüfung in Berlin, Germany. They offer the determination of material properties as a service.
Cheng / Song, Split Hopkinson Bar

Technology used

Other case studies

Showing 9 of 511 items
No more result to load