Measurement of the Contacting Stress in Hot Extrusion using Optical Fibers

研制了一种新型的挤压接触应力传感器，采用光纤位移计测量挤压接触应力。(1)光纤压力传感器的研制了一种新型的光纤位移计压力传感器。从工具的后侧开一个孔，以在工具表面上保留一个圆形薄板。可以使用光纤位移计从薄板的变形检测压力。利用该传感器测量了圆柱体压缩过程中作用在工具表面的压力分布。该传感器的特点是能在有润滑和刀具与材料之间有较大滑动的情况下检测接触应力。(2)应用于挤压过程，测量了挤压接触面上的压力分布。在润滑的情况下，容器表面上的压力几乎恒定。另一方面，由于容器表面上的摩擦力，压力根据与模具出口的距离而增加，没有润滑。(3)未来的课题光纤探头的耐热性有待提高。研制了双光纤探头的悬臂式应力传感器。

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 fibersA 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 extrusionPressure 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 futureHeat proof of the optical fiber probe will be improved. Frictional stress sensor using two optical fiber probes wiII be developed.