Author: Tadahiro Shibutani

Highly accelerated limit test (HALT) is a qualitative accelerated method for testing electronic products as introduced in IEC62508. The purpose of HALT is to identify specific failure modes of units by generating external stresses. HALT has been adopted for many products, and some companies use HALT to improve the design process of their products. However, failure mechanism of products during HALT is too complex, and it is not easy to identify a problem in the tested product.

The goal of our group is to identify fundamental failure mechanisms of products during HALT.

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• Potential failure mode identification of operational amplifier circuit board by using high accelerated limit test, Junji Sakamoto, Ryoma Hirata, Tadahiro Shibutani, Microelectronics Reliability, Volume 85, pp. 19-24, 2018. https://doi.org/10.1016/j.microrel.2018.04.005

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Structural integrity is the ability of structure or a component resisting failure due to fracture and/or deformation. A piping system is a key in industrial facilities such as energy plants. In particular, seismic events can place severe stresses on piping systems. Supplemental loads and dynamic motion may induce a strong cyclic bending moment in pipes. Our group aims to clarify failure mechanism of aged piping systems under seismic loadings. This project is collaborative research between National Research Institute for Earth Science and Disaster Prevention (NIED), IHI Corporation, and YNU. Figure shows that failure occurred at wall-thinned tee in the piping system subjected to seismic loads.