The determination of inclusion movement in steel castings by positron emission particle tracking (PEPT)
- 151 Downloads
The movement of inclusions in casting has been studied using radioactive labelling of ceramic particles, a process known as positron emission particle tracking (PEPT). Alumina and silica particles of size about 355–710 μm were made radioactive in a cyclotron, by the partial conversion of oxygen to 18F. This isotope has a half-life of 110 min, giving a window of time of around 3 h in which the particles could be detected by this technique. Individual radioactive particles were placed in ceramic moulds at known initial positions, which were then filled with low carbon steel, causing the particle to be entrained into the metal stream during the casting process. After the casting had solidified, the final position of the radioactive particle was determined using a γ-ray positron camera. The initial and final co-ordinates of the deliberately entrained inclusions within the casting could then be obtained, with an accuracy of around 5 mm.
KeywordsSilica Particle Casting Process Alumina Particle Steel Casting Metal Stream
The authors would like to thank Dr. J-C Gebelin, Dr. S. Jones and Mr. A. Caden, of the Department of Metallurgy and Materials Science at the University of Birmingham, for their technical assistance.
- 1.Kiessling R (1989) Non-metallic inclusions in steel, part III. The Institute of Materials, LondonGoogle Scholar