01_fundamentals Of Metalworking

Transcript

  Fundamentals of Fundamentals of metalworkingmetalworking Suranaree University of Technology Jan-Mar 2007 Subjects of interest  ã Introduction/objectivesã Classification of metal processesã Mechanics of metalworkingã Flow curvesã Effects of temperature on metalworking- Hot working- Cold workingã Effects of metallurgical structure on forming processesã Effects of speed of deformation on forming processesã Effects of friction and lubricant Chapter 1 Tapany Udomphol  ObjectivesObjectives Suranaree University of Technology Jan-Mar 2007 ã This chapter provides classification of metal formingprocesses based on types of forces applied onto metals.ã Mechanics of metal forming will be outlined to understandstress criterion for plastic deformation.ã Differences between hot and cold working will be highlightedand advantages-disadvantages of hot and cold working will begiven.ã Effects of deformation speed and friction on metal workingprocess will be included. Tapany Udomphol  Classification of metal formingClassification of metal formingprocessesprocesses Suranaree University of Technology Jan-Mar 2007 (based on the type of force applied on to the work piece asit is formed into shape). ã Direct-compression-type processes ã Indirect-compression processes ã Tension type processes ã Bending processes ã Shearing processes Tapany Udomphol  ã Direct-compressiontype processes : the applied force is normal tothe direction of the metal flow in compression, i.e., forging and rolling processes. ã Indirect-compression type processes : the primary forces are frequently tensile , with indirect compressiveforces developed by the reaction of the work piece. The metal flow istherefore under the combined stress state, i.e., extrusion, wiredrawing,tube drawing. Suranaree University of Technology Jan-Mar 2007 Tapany Udomphol