N. Razani - MSc. Student, Department of Engineering and High Tech, Iran University of Industries and Mines
B. Mollaei Dariani - Associate Professor, Mchanical Department, Amirkabir University
A. Jalali Aghchai - Assistant Professor, Department of Engineering and High Tech, Iran University of Industries and Mines

One of the important mechanical properties of flow-formed tubes is hardness. Design of experiment has been used to investigate the effects of flow forming parameters such as rotational speed of mandrel, feed rate and dept of cut of roller on the hardness of flowformed AISI 321 steel tube. A mathematical prediction model of the hardness was developed using response surface methodology (RSM). RSM's Box-Behanken design was employed for determining the optimum forming condition for minimum hardness at %95 optimum confidence level. The hardness was found to increase with increase in the mandrel speed and the depth of cut and it decreased with decrease in the feed rate.

flow forming - AISI 321 steel tube – hardness - RSM