An electromechanical UTM utilizes an electric motor to apply a controlled force, while a hydraulic UTM uses hydraulic systems for force application. Electromechanical UTMs are favored for their precision, speed, and ease of use, making them suitable for a wide range of applications, including tensile, compression, and flexural testing.
On the other hand, hydraulic UTMs are capable of generating higher forces and are often used for testing high-strength materials such as metals and alloys, where extreme force applications are required. Both types of UTMs play critical roles in various industries including aerospace, automotive, construction, and materials science, enabling engineers and researchers to accurately assess the mechanical properties of materials for design, quality control, and research purposes.
Several variations are in use.2 Common components include:
The set-up and usage are detailed in a test method, often published by a standards organization. This specifies the sample preparation, fixturing, gauge length (the length which is under study or observation), analysis, etc.
The specimen is placed in the machine between the grips and an extensometer if required can automatically record the change in gauge length during the test. If an extensometer is not fitted, the machine itself can record the d e systems including any slipping of the specimen in the grips.
Once the machine is started it begins to apply an increasing load on specimen. Throughout the tests the control system and its associated software record the load and extension or compression of the specimen.
Machines range from very small table top systems to ones with over 53 MN (12 million lbf) capacity.34
Davis, Joseph R. (2004), Tensile testing (2nd ed.), ASM International, p. 2, ISBN 978-0-87170-806-9. 978-0-87170-806-9 ↩
Annappa, C H (July 2012), "APPLICATION OF VALUE ENGINEERING FOR COST REDUCTION – A CASE STUDY OF UNIVERSAL TESTING MACHINE", International Journal of Advances in Engineering & Technology, 4 (1): 618–629, retrieved 1 December 2017 https://www.researchgate.net/publication/283008884 ↩
NIST, Large Scale Structure Testing Facility, archived from the original on 5 June 2010, retrieved 4 May 2010. https://web.archive.org/web/20100605214812/http://www.nist.gov/bfrl/facilities_instruments/large_scale_struct_testing_fac.cfm ↩
Kirstein (1971). Universal Testing Machine of 12-Million-lbf Capacity, NBS Pub 355 (PDF) (Report). NIST. Retrieved 22 May 2017. http://nvlpubs.nist.gov/nistpubs/Legacy/SP/nbsspecialpublication355.pdf ↩