1991 Fiscal Year Final Research Report Summary

Measurement of the Contacting Stress in Hot Extrusion using Optical Fibers

Research Project

Project/Area Number	02452107
Research Category	Grant-in-Aid for General Scientific Research (B)
Allocation Type	Single-year Grants
Research Field	機械工作
Research Institution	The University of Tokyo
Principal Investigator	HATAMURA Yotaro The University of Tokyo, Faculty of Technology, Professor, 工学部, 教授 (40010863)
Co-Investigator(Kenkyū-buntansha)	YONEYAMA Takeshi Kanazawa University, Faculty of Technology, Associate Professor, 工学部, 助教授 (30175020)
Project Period (FY)	1990 – 1991
Keywords	Metal forming / Extrusion / Pressure / Optical fiber / Measurement / Tribology / Sensor
Research Abstract	A new stress sensor has been developed for the measurement of contacting stress in extrusion using an optical fiber displacement meter. (1) Development of a pressure sensor using optical fibers A new pressure sensor using an optical fiber displacement meter has been developed. A hole has been made from the rear side of the tool to remain a circular thin plate on the tool surface. Pressure can be detected from the deformation of the thin plate using an optical fiber displacement meter. Pressure distribution acting on the the tool surface in the compression of a circular cylinder has been measured using the sensor. The characteristic of the sensor is to be able to detect the contacting stress with lubrication and in the condition of large slip between the tool and the material. (2) Application to the extrusion Pressure distribution acting on the contacting surface has been measured using the developed sensor. Pressure is nearly constant on the container surface with the lubrication. On the other hand, Pressure increases according to the distance from the die exit owing to the friction on the container surface with no lubrication. (3) Subjects for the future Heat proof of the optical fiber probe will be improved. Frictional stress sensor using two optical fiber probes wiII be developed.