Made Of Ultra-Fine Grained Construction Material By Transferring The Severe Plastic Deformation Zone During Friction Torsion Under Pressure

To obtain large bulk material with ultra-fine grain for the requirements of property measurement and engineering utilization, the transformation of friction press-torsion deformation zone was introduced in this paper. Both the transmit of heat theory and the plastic mechanical theory were practiced to analyse the mechanical and deformation qualification. With the unique self-made cooling system, the LY12 is researched through the above method and the ultra-fine grain was obtained. The mechanical capability, dilatability and stability of these microstructures at elevated temperatures were also studied.The results indicated that, the fabrication process of ultra-fine grain material is mainly determined by the stress, rotate speed and the flux of cooling water. The grain refining and the hardening effect are mostly affected by the rotate speed and the flux of cooling water. Compared with commercial LY12, the invalidate strength and the prolongation rate of the ultra-fine grain material are properly improved in the measurement of compression property; and the abrupt change of the dilatability of the ultra-fine grain material at 500C is found; also the phenomena of which the grain size of these microstructures is stable when annealed under 300C is observed.