New Aspects of Rebound Hardness Testing Method

2014 Fiscal Year Final Research Report

• Project/Area Number: 25630039
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Design engineering/Machine functional elements/Tribology
• Research Institution: Kyushu Institute of Technology
• Principal Investigator: MATSUDA Kenji 九州工業大学, 大学院工学研究院, 教授 (40229480)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: 反発硬さ試験 / 反発係数 / 脆性材料 / 破壊じん性値 / 潤滑油 / ハンマ振動

Outline of Final Research Achievements

(1) If a specimen is fixed by inadequate manner, the hammer is released from the specimen surface before the elastic deformation of the specimen has been restored, and then the vibration of the specimen after the impact increases, which results in one of the causes of decreasing in the coefficient of restitution. (2) In the case of the hammer with a pyramidal tip and a high rigidity body, the coefficient of restitution remains almost a constant value irrespective of the existence of the lubricant on the specimen surface and of the impact velocity. (3) There exists a kind of glass of which almost a constant coefficient of restitution can be obtained irrespective of the impact velocity when the hammer mentioned in the above item (2) is used. Furthermore, it becomes clear that the deformation and destructive behaviors of glass due to the collision could strongly affect the hammer motion after the impact.

Free Research Field

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