May 15, 2014
New computer-controlled tri-axial fatigue testing machine for precise emulation of mechanical fatigue
Hitachi, Ltd. announced the development of a new computer-controlled tri-axial material fatigue testing machine to emulate the complex stress conditions subjected during operation on mechanical structures such those in construction machinery and renewable energy facilities. When the testing machine was used to emulate the stress conditions on actual construction machinery using a test specimen, it was found that stress conditions could be emulated within an error range of less than 3%. By applying this fatigue testing machine to optimizing the design of social infrastructure products, Hitachi will be able to achieve the most appropriate structural design in line with the use conditions thus contributing to improved reliability as well as reducing material costs.
Reliable operation over a long time span is extremely important in mechanical structures supporting social infrastructure such as railways, construction machinery and wind turbines. Stress is generated on the surface of mechanical structures through structural deformations in the transverse, longitudinal and diagonal directions. Previous studies have reported that fatigue fractures of mechanical structures tend to be accelerated if working stressors become multi-directional.
In conventional material tests, it was possible to elucidated the fatigue phenomena in relation to unidirectional load but technical difficulties in applying a multi-directional stress load on a test specimen prevented the emulation of arbitrary stress on test specimens. To overcome this, Hitachi has developed a new tri-axial material fatigue testing machine which is able to apply complex stress conditions on a test specimen, emulating real-world operating conditions.
