2010 Fiscal Year Final Research Report

The mechanism of spontaneous growth of Pb nano-whiskers on the surfaces of brasses

Research Project

Project/Area Number	20510092
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	Environmental technology/Environmental materials
Research Institution	National Institute of Advanced Industrial Science and Technology
Principal Investigator	SUN Zhengming National Institute of Advanced Industrial Science and Technology, サステナブルマテリアル研究部門, 主任研究員 (70344190)
Co-Investigator(Kenkyū-buntansha)	HASHIMOTO Hitoshi 独立行政法人産業技術総合研究所, 東北産学官連携センター, 総括主幹 (70357771)
Project Period (FY)	2008 – 2010
Keywords	人間生活環境 / Cu-Zn合金 / 鉛毒性 / 応力 / 再結晶
Research Abstract	Spontaneous growth of lead whiskers at ambient temperature in various brass alloys were observed on the cut or ground surfaces. Residual stresses were measured on the surfaces but were found irrelevant to the whisker growth from the alloys. The results of thermal analysis demonstrated that while well-defined endothermic peaks, caused by melting of lead, were measured during heating, no well-defined exothermic peak during cooling was observed. This implies the possibility of the existence of supercooled lead in brasses, which is responsible for the spontaneous lead whisker growth. Long term exposure to air at 60℃ did not affect the whisker formation.

(5 results)