Particle Internal Fracture Energy Measurement by Ultrafast Load Cell

Ultrafast Load Cell (UFLC) device is used in micro-scale modeling of particle fracture. Electro-mechanical device measures the internal fracture energy of the particles during the fracture event under impact. The sphere and/or cylinder weight is dropped onto particle staying on a plane cylinder surface. The point where the particle is divided into two pieces without secondary, tertiary breakages is called the fracture point. UFLC is equipped with two Wheatstone bridges. These bridges convert compressive strain signals produced during the impact event to a voltage signal. This signal can be expressed as force, energy, and displacement. All the information gained during the fracture is then used to estimate breakage rates of the particles. In this study, two parameter Weibull distribution is used in modeling the internal fracture energy distributions of the particles those ranges between 7mm and 45mm. It is concluded from the study that the median internal specific fracture energy of the particles of the size 45mm and 7mm are 2.2 Joule /kg and 25.4 Joule /kg, respectively. This study quantitatively shows the relationship between the particle specific fracture energy and the size.

Anahtar Kelimeler:

Ultrafast Load Cell (UFLC), Fracture; Impact energy; Modeling; Grinding

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